May 2018 Global Temperature Update

may 2018 global temp fig1.png

May 2018 global temperature, at 0.82°C relative to the 1951-1980 base period, was the fourth warmest May since reliable measurements began in 1880.  The warmer Mays were in 2016 (+0.91°C), 2017 (+0.88°C) and 2014 (+0.85°C).  Northern Hemisphere spring (March-April-May) 2018 was the third warmest spring at 0.86°C (See the figure above), while the warmest were 2016 (1.10°C) and 2017 (0.97°C).  Note that the most of the U.S. was extremely cold in April and very warm in May.

Using the base period 1880-1920 which provides our best estimate of pre-industrial temperature, the May 2018 anomaly was 1.09°C.  Post-El Nino cooling has probably bottomed out, given that equatorial Pacific Ocean temperatures have begun to rise (See the left side of the figure below).  We conclude that global warming, with short-term variability excluded, has reached the level of at least +1.1°C relative to pre-industrial temperature.

may 2018 global temp fig2.png

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Get Out of Jail Free Card: Carbon Capture

Get Out of Jail Free Card: Carbon Capture

12 June 2018

James Hansen

I am minimizing Communications, so that I can (really!) finish Sophie’s Planet, while also providing expert testimony for several lawsuits aimed at using the judicial branch of government to force the other branches of government to do their job.  However, there is enough popular misinterpretation of recent news about the cost of carbon capture that I should comment on that. 

David Keith has done some of the most credible work on direct air capture of CO2, so his recent paper[1] in Joule reporting on the cost of carbon capture deserves attention.  Media reports emphasized that these reported costs were lower than costs estimated in a report by the American Physical Society (APS) in 2011.  This caused some people to believe that we may be on the way to a “get out of jail free” card, the hope of many that technology will come to the rescue, so we do not need to be so concerned about the mess we are leaving for young people.

Unfortunately, the new news on carbon capture costs provides no support for the notion that we can solve the climate problem without fossil fuel phase-out.  On the contrary, the Keith et al. study reinforces our concerns.

Many people failed to notice the matter of units.  Keith reports a cost of $113-232 per ton of CO2 for plant designs in which the resulting CO2 is ready for sequestration   The cost per ton of carbon (tC) is higher by the factor 44/12.  So the reported cost is $414-850/tC. 

Furthermore, none of the four cases include the cost of carbon storage!  According to the 2015 National Academy of Sciences report on CO2 removal[2] the costs of geological sequestration are $37-73/tC.  So the total costs for capture plus storage would be $451-923/tC. 

Note that we used the cost range $113-232/tCO2 from the Keith paper.  They also give a cost range $94-232/tCO2, which is what the media picked up on.  However, the $94 case has the CO2 being used to make a liquid fuel that, when burned, puts the CO2 back in the air!  So there is no negative emission.  In fact, that total process would have positive emissions, at least to some degree. 

In Young People’s Burden we were aware that the cost estimates from the APS study were high.  Based on many studies referenced in our paper, we chose $150-350/tC as an optimistic estimate of the potential future cost.  The low end of the cost range $451-923/tC  based on Keith et al. is about 30% higher than the upper end of our range!

In Young People’s Burden we show that even our very optimistic cost of carbon capture results in an unbearable debt for young people, if high emissions continue unabated.  The new estimates only reaffirm that conclusion.  There is no prospect for a Get-Out-of-Jail-Free card.

One of the legal cases[3] now underway is an effort to block the Trump government from opening up a huge new area of coal mining in Montana.  The total coal resources in the basin in question are twice the quantity produced in the entire U.S. since 1949!  Burning even a fraction of these resources would leave an astronomical cost for young people, as I show in the linked declaration I submitted to support the case against expanding that mining. It makes no sense to exploit these resources, serving only to enrich a handful of people.  Most of the coal would be shipped to the Far East, but, in the end, I do not believe that the United States can escape either the moral or legal obligations from such a willful disregard of the consequences for young people.  It makes no sense to approve such expansion of coal mining, and I believe that chances of blocking that expansion are good.

[1] Keith, D.W., et al.: A process for capturing CO2 from the atmosphere, Joule, 2, 1-22, 2018.

[2] National Academy of Sciences: Climate Intervention: Carbon Dioxide Removal and Reliable Sequestration, Washington, D.C., 154 pp., https://doi.org/10.17226/18805, 2015.

[3] Montana Environmental Information Center v. U.S. Office of Surface Mining and Signal Peak Energy, LLC. Doc. 86.

I have a new assistant, Eunbi Jeong <ej2347@columbia.edu>, replacing Nicole.  If you are interested and able to support our work at Climate Science, Awareness and Solutions, you can contact Eunbi.

 

APRIL 2018 GLOBAL TEMPERATURE UPDATE

April 2018 Global Temp Update figure.png

Two-thirds of North America was very cold in April (left side of figure above), but globally April 2018, at 0.86°C relative to the 1951-1980 base period, was the third warmest April since reliable measurements began in 1880.  The warmest Aprils were in 2016 (+1.07) and 2017 (+0.92°C)!

The right side of the figure above compares monthly temperatures in the years 2015-2018. 

Post-El Nino cooling has probably bottomed out, given that equatorial Pacific Ocean temperatures have begun to rise.  We conclude that global warming, with short-term variability excluded, has reached the level +1.1°C relative to pre-industrial temperature, as shown in the figure below.

Note that base period 1880-1920, used for the figure below, provides our best estimate of pre-industrial temperature, as discussed in our Young People’s Burden paper (Earth System Dyn., 8, 1-40, 2017).

Also note that the reason we employ base period 1951-1980 in the figure above is the absence of earlier data for Antarctica, much of the Southern Ocean, and parts of Africa and South America.  There are enough data points to define a global mean temperature, but not to define a global map.

April 2018 Global Temp Update figure2.png

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March 2018 Global Temperature Update

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Globally March 2018 was the sixth warmest March since reliable measurements began in 1880, 0.89°C warmer than the 1951-1980 mean.  March temperature was +1.16°C relative to the 1880-1920 base period that provides our best estimate of pre-industrial global temperature.  March temperatures relative to 1951-1980 mean, in order from the warmest, were +1.30°C (2016), +1.12°C (2017), +0.92°C (2010), +0.91°C (2002) and +0.90°C (2015).

The figure above compares monthly temperatures in the years 2015-2018.  Note that temperature began rising in the latter part of 2015 as an El Nino was developing.  That late 2015 warming led to record 2016 global heat.  Some ocean models predict that an El Nino may develop later this year, in which case 2019 could be a very hot year.  Historical precedence does not favor the occurrence of two strong El Ninos separated by only 3 years.  On the other hand, the human hand may be altering history.

January-March this year was the 4th warmest on record, but the maps below for the geographical distribution of the temperature anomaly confirm that Europe and the U.S. were not particularly warm.  However, it was nothing like the extreme 2015 cold period in the eastern part of Canada and the U.S., which caused some of the public to doubt the reality of global warming.

pic2.png

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Youth and Colombia Forests

Youth and Colombia Forests

16 March 2018

James Hansen

Tropical deforestation does more than fuel global climate change, threatening all people.  It also affects life prospects of local youth.  So I am happy to see young people in Colombia stand up for their rights.  Yesterday my legal adviser Dan Galpern filed my Amicus Brief in Colombia to support 25 plaintiffs, youth between ages 7 and 26, who are filing a tutela (guardianship) action, a mechanism that the Colombian Constitution provides to protect fundamental rights of individuals to a dignified life, health, food and water.  The plaintiffs can be seen here.

Deforestation threatens fresh water supplies, as half of the rain that falls in the Colombian Amazon is recycled rain.  The impact of deforestation on ecosystems and freshwater, together with climate change, risks public health by helping spread vector-borne diseases such as dengue, chikungunya and zika.

Colombia, in the precatory 2015 Paris climate accord, committed to zero-net deforestation in the Colombian Amazon, the most biodiverse region in the world, by 2020.  Instead the nation allowed deforestation to skyrocket in 2016 by 44 percent.

The legal action of the 25 youth has been filed before the Superior Tribunal of Bogota, with the support of Dejusticia.  Dejusticia is a Colombia-based research and advocacy organization dedicated to the strengthening of the rule of law and the promotion of social justice and human rights in Colombia and the Global South.

The youth are asking the government to formulate an action plan within six months to reach zero-net deforestation in the Colombian Amazon.  Further, they are asking the government for an Intergenerational Agreement in which the authorities will commit to take effective and quantifiable measures to reduce greenhouse gas emissions

February 2018 Global Temperature Update

To sign up for our monthly update of global temperature (Maps and Graphs), click here.
Additional figures are on our global temperature web page.

Globally February 2018 was the sixth warmest February since reliable measurements began in 1880, 0.78°C warmer than the 1951-1980 mean.  February temperature was +1.06°C relative to the 1880-1920 base period that provides our best estimate of pre-industrial global temperature.  February temperatures relative to 1951-1980 mean, in order from the warmest, were +1.34°C (2016), +1.12°C (2017), +0.90°C (1998), +0.87°C (2015) and +0.79°C (2010).  A comparison of the monthly mean temperatures for 2015-2018 is shown in the figure above.

febtemp2018.png

As one of the maps above shows, February was cold in Western Europe and Japan, but a large region from Canada to the northern central US was 4-6°C colder than the 1951-1980 mean, while the Arctic region was 8-12°C warmer than normal.  Such cold air outbreaks from the Arctic to middle latitudes, with accompanying movement of warm mid-latitude air into the Arctic, have always occurred because of natural variability of atmospheric wind patterns.  However, there is evidence (Cohen et al., 2018) that the frequency of winter cold air outbreaks from the Arctic has increased as a result of global warming.  Average warming is greater in the Arctic than at lower latitudes, in part because global warming reduces the area of Arctic sea ice, which amplifies the polar warming.  The greater polar warming reduces the temperature gradient between low and high latitudes that drives the mid-latitude jet stream, the west-to-east wind in the upper troposphere.  A weaker jet stream tends to be more “waggly,” increasing the occurrence of Arctic cold air outbreaks.

The situation is different in the Antarctic.  The surface of the Southern Ocean is warming more slowly than most of the planet, in part because of the cooling and freshening effects of increasing ice discharge from Antarctic ice shelves (Hansen et al., 2016).  This cooling effect on the surface of the Southern Ocean competes regionally with the warming effect of increasing greenhouse gases.  There is large year-to-year variability; the strong 2016-17 El Nino caused a decrease of Southern Ocean sea ice over the past two years.  However, if melting of Antarctic ice shelves and ice sheets continues to increase, the warming of the Southern Ocean will continue to be much less than warming in the rest of the world.

Cohen, J., K. Pfeiffer and J.A. Francis, Warm Arctic episodes linked with increased frequency of extreme weather in the United States, Nature Comm., publ. online 13 March 2018.

Hansen, J., M. Sato, P. Hearrty, R. Ruedy, M. Kelley, V. Masson-Delmotte, G. Russell, G. Tselioudis, J. Cao, E. Rignot, I. Velicogna, B. Tormey, B. Donovan, E. Kandiano, K. von Schuckmann, P. Kharecha, A.N. Legrande, M. Bauer, and K. Lo, Ice melt, sea level rise and superstorms: evidence from paleoclimate data, climate modeling, and modern observations that 2°C global warming could be dangerous, Atmos. Chen. Phys., 16, 1-52, 2016.

Some Basis for Optimism

Some Basis for Optimism

08 March 2018

James Hansen

Pessimism has plenty of basis today: it is easy to point out many negative trends, an increasing polarization of politics, and the lack of easy solutions.

However, optimism also has plenty of basis, mostly related to young people.  Some examples:

(1) The U.S. Court of Appeals in San Francisco rejected the Trump Administration’s attempt to block the lawsuit of Our Children’s Trust demanding a plan by the United States government to reduce fossil fuel emissions.  The trial will proceed in the U.S. District Court in Oregon, likely in the fourth quarter of this year.  Surely we will win the case there, and it will likely end up in the Supreme Court.  I expect that even a conservative Court will require climate action by our government.

Yes, the courts are slow, but our paper Young People’s Burden: Requirement of Negative CO2 Emissions shows that even with actions beginning in 2021 it is readily possible to keep global warming within targets specified by the United Nations.  Further, there are actions that make sense for other reasons that will help draw down excess atmospheric CO2, as I discuss further in the upcoming Sophie’s Planet.

(2) Young Republicans are showing that they will not accept politics as usual, they understand climate change is real, and a substantial number of them advocate exactly the conservative policy that could address the matter successfully: carbon fee with 100% dividend uniformly distributed to the public.  See NY Times article below.

My opinion is that the polarization of our politics in the United States has proceeded so far that recovery depends upon the rise of a third party, for reasons I describe in Sophie’s Planet.  I would suggest American Party as a name, with objective to make America America again.  However, it is all going to be up to young people.  Predicting future politics is more difficult than predicting climate.  What I am trying to do in Sophie’s Planet is describe what I have seen in the past three-quarters of a century, and what I think the implications are.

(3) Another basis for optimism is the rapid progress of Michael Shellenberger as an Independent candidate for California Governor.  Except for Barack Obama and his wasted opportunities, nobody has been more frustrating than Jerry Brown.  Californians are among the most environmentally conscious people in the world, so it is a shame that they have been saddled with a Limousine Liberal who gallivants around the world pretending to be an environmentalist.  I quantify Jerry Brown’s effect on California’s greenhouse gas emissions in Sophie’s Planet.

 

 

College Republicans Propose an Unusual Idea From the Right: A Carbon Tax

The New York Times     By Lisa Friedman   March 6, 2018

 

Alexander Posner, right, at a meeting of Students for Carbon Dividends at Yale University. The group pulls together millennial-aged conservatives to promote acceptance of climate change and propose conservative solutions. Credit Christopher Lee for The New York Times

As the Republican Party struggles to find its footing with the next generation of voters, several conservative college groups have banded together to champion something anathema to the party: a carbon tax.

The group is led by the Yale College Republicans, the main campus student organization for young Republicans at Yale, and includes other prominent Republican groups at 22 other schools around the country including Clemson University in South Carolina, North Carolina State University and Texas Christian University in Fort Worth, Texas. Under the name Students for Carbon Dividends, the coalition is backing an idea first broached by Republican heavyweights including former Secretary of State James A. Baker III and former Secretary of State George P. Shultz: Tax the carbon pollution produced by burning fossil fuels and then return the money to consumers as a dividend in the form of monthly cash payments to individuals, both adults and children alike.

Late last month, several of the campus Republican leaders involved in the climate change coalition visited Washington to volunteer at the Conservative Political Action Conference, the annual gathering of conservative activists and politicians.

Republican strategists said the budding movement reflected an important shift on social and environmental issues that could divide the party along generational lines. Political polls suggest that millennials are dissatisfied with what they see as politics as usual from both parties. But Republicans said they worried their ranks would bear the brunt of the shift as young people moved away from party orthodoxy on issues like guns, gay marriage and climate change.

“I think what we see is that, at a time when younger voters are rejecting party politics broadly, they’re rejecting the Republican Party at a much higher rate because what they see, according to them, is a party that doesn’t want to listen and doesn’t want to grow,” said Doug Heye, a former communications director for the Republican National Committee.

“It’s a problem right now, but it’s going to be a catastrophic problem in five years or 10 years,” Mr. Heye said.

The leaders of nearly two dozen Republican student groups involved in the coalition said they and their peers accepted the scientific consensus that humans have played a significant role in warming the planet. Many said they were tired of hearing Republican leaders deny climate change and did not want their party branded as anti-science.

“As a party, we’re losing voters rapidly because of this issue,” said Kiera O’Brien, president of Harvard University’s Republican club, which is a member of the carbon-tax coalition. “I’m increasingly frustrated by the fact that the science is disputed when there’s clearly evidence of climate change. We need to have a solution for our party, but we also need a solution that’s an alternative between doing nothing or ceding everything to the government.”

By embracing what they call a conservative approach, the students said they hoped to help move the Republican Party on the issue.

Under the plan the students are proposing, an initial tax of $40 per ton of carbon would be levied at the point where fossil fuels enter the economy, for instance a mine or port. The tax would increase over time. That money would then be returned to taxpayers in a per-person monthly payment, with half-payments going to children under the age of 18 and a limit of two children per family. The Climate Leadership Council created by Mr. Baker and Mr. Shultz estimates a dividend would amount to about $2,000 a year for a family of four.

As part of the deal, there would also be limitations on regulatory actions like the Clean Power Plan, which former President Barack Obama imposed to reduce carbon emissions from coal-fired power plants. Members of the coalition said they considered a promise to scale back future regulation key to encouraging Republican support.

Alexander Posner, 22, a Yale University senior who founded the group, said he has been interested in climate change and energy for years. When he read about the climate council Mr. Baker and Mr. Shultz began last year, he signed up for an internship. Soon after, he started contacting his peers at Republican clubs across the country to sound them out on creating a coalition of their own.

“We’ve had a lot of conversations, and literally not once has the validity of climate science come up,” Mr. Posner said. “I think students really want to have a solutions-based discussion.”

The coalition of 23 Republican student groups, five college Democratic clubs and three university environmental clubs comes at a unique moment of youth political activism. Students nationwide are mobilizing for gun control, inspired by the survivors of the school shooting in Parkland, Fla., and Mr. Posner said that, despite the profound differences in the two movements, young Republicans working on issues like climate change were watching the gun protests with interest.

“I think the common theme here is if representatives are not responding to the desires of their constituents, in particular young people,” he said, “then young people are going to step forward. This coalition on the climate front is sort of a reflecting of the inaction of adults.”

Last week the nonprofit Alliance for Market Solutions issued a survey on millennial attitudes toward climate change showing that nearly 60 percent of young Republicans acknowledge that human-induced climate change is real, and 88 percent of young Democrats. A majority of young people of both parties said they believed steps should be taken to slow or stop climate change.

“Young voters don’t necessarily have strong views on what should be done about climate change, but doing nothing is not a path that most young people, including Republicans, tend to support,” said Kristen Soltis Anderson, the Republican strategist who conducted the survey.

Harrison Preddy, 22, a senior majoring in political science at North Carolina State University, said he was skeptical when he first saw Mr. Posner’s email asking him to embrace a carbon tax and dividend. But when the two spoke on the phone, Mr. Preddy said, “it started to speak to what I had been feeling we were missing for so long.”

Raised on a tobacco farm about 45 minutes outside of Raleigh, N.C. — Mr. Preddy jokes that his family couldn’t afford pesticides, so they were organic farmers before it was cool — he said accepting the science of climate change was not a leap for him because his family had long been attuned to shifting weather patterns. But, he said, he rejected the solutions put forward by Democrats, including regulations like the Clean Power Plan, because he believes they ignored economic hardships posed on communities that depend on fossil fuel production.

NYT pic.png

Kiera O’Brien, left, president of Harvard University’s Republican club, and Harrison Preddy, a senior at North Carolina State University, both support the idea of a carbon tax and dividend. Credit Becky Harlan for The New York Times

 “I’m a strong believer that we need to take action, but at the same time I understood the plights of coal miners, the plight of economic restructuring. It’s a heart-string issue for me,” Mr. Preddy said.

Ms. O’Brien said growing up the daughter of a biology teacher near the Tongass National Forest in Alaska taught her a respect for both science and the environment. Ms. O’Brien said she has found the lack of a coherent Republican Party position on climate change her single biggest challenge in recruiting students to the conservative movement.

“The question I will frequently get is, ‘Why do you hate the planet? Why do you not like science?’” she said. “We can’t be a party that’s entrenching itself in a dying planet.”

Dylan Jones, chairman of the Republican club at the University of Kansas, called addressing climate change a pro-life issue. Mr. Jones, a strong supporter of President Trump, said he questions a good deal of what is said about climate change. But, he said, he believes lawmakers should find a way to protect the planet.

“If the Republican Party is really the party of life, then we fight for life under every circumstance,” he said. “Now it’s time for young people like myself to come up with ideas and solutions so we can be part of the discussion and debate instead of sitting on the wayside and denouncing science.”

The Republican National Committee did not return a call to discuss the group’s proposal or its strategy toward younger conservatives. The party platform established ahead of the 2016 presidential election takes no position on the science of climate change other than to say the United Nation’s scientific body, the Intergovernmental Panel on Climate Change is “a political mechanism, not an unbiased scientific institution,” and that its conclusions should be assessed in that context. The I.P.C.C. is the principal international scientific body charged with reviewing climate science and issuing reports about the risks to the world's government.

Mr. Baker said in an interview he believes the idea of a carbon tax and dividend can appeal to those who question climate change science. “I’m sort of a climate change skeptic,” he said. “I do think the climate is changing but I don’t know why, and I sure don’t understand the extent to which man may be responsible for it.”

But, Mr. Baker added, uncertainty about the magnitude of the threat shouldn’t be an excuse not to act. “This is a free-market based solution,” he said.

Correction: March 7, 2018.  An earlier version of this article misspelled the surname of a former secretary of state in several instances. He is George P. Shultz, not Schultz.

Lisa Friedman reports on climate and environmental policy in Washington. A former editor at Climatewire, she has covered eight international climate talks. @LFFriedman  A version of this article appears in print on March 7, 2018, Page A13 of the New York edition with headline: Unusual Plan From Young Conservatives: Carbon Tax.

Rock Dust in Farming Redux

Rock Dust in Farming Redux

21 February 2018

James Hansen

In my 19 February Communication on ‘Rock Dust in Farming,’ which discusses a study led by David Beerling and his group in Sheffield, UK, I failed to mention a few points.

(1) The principal net result of the proposed approach, enhanced silicate weathering, is to store carbon in the ocean, mainly as limestone on the ocean floor.  The idea is to speed up the natural weathering process that takes CO2 from the air and deposits carbon in the ocean.  This approach has the added benefit of reducing ocean acidification, thus helping to protect corals and shellfish.  This approach is thus different than, and additional to, methods, such as biochar addition and minimal plowing, which aim to store more carbon in the soil.

(2) Some readers were disappointed that there is a charge to acquire the article (abstract below).  The journal of publication does not allow the common practice of authors paying additional page charge for open access, but they do allow free viewing (no downloading) of the article.  I should have included the link for viewing: http://rdcu.be/HlCp

(3) Google screening of e-mails has become strict.  My Communications now seem to end up in Promotions or worse.  If you are signed up and want to receive them in your primary inbox, you need to find one, move it to your primary inbox and affirmatively answer the question about whether you want future ones there.

Farming with crops and rocks to address global climate, food and soil security

 

David J. Beerling, Jonathan R. Leake, Stephen P. Long, Julie D. Scholes, Jurriaan Ton, Paul N. Nelson, Michael Bird, Euripides Kantzas, Lyla L. Taylor, Binoy Sarkar,            Mike Kelland, Evan DeLucia, Ilsa Kantola, Christoph Muller, Greg H. Rau, James Hansen

 

The magnitude of future climate change could be moderated by immediately reducing the amount of CO2 entering the atmosphere as a result of energy generation and by adopting strategies that actively remove CO2 from it. Biogeochemical improvement of soils by adding crushed, fast-reacting silicate rocks to croplands is one such CO2-removal strategy. This approach has the potential to improve crop production, increase protection from pests and diseases, and restore soil fertility and structure. Managed croplands worldwide are already equipped for frequent rock dust additions to soils, making rapid adoption at scale feasible, and the potential benefits could generate financial incentives for widespread adoption in the agricultural sector. However, there are still obstacles to be surmounted. Audited field-scale assessments of the efficacy of CO2 capture are urgently required together with detailed environmental monitoring. A cost-effective way to meet the rock requirements for CO2 removal must be found, possibly involving the recycling of silicate waste materials. Finally, issues of public perception, trust and acceptance must also be addressed.

Rock Dust in Farming: A Potential Strategy to Help Close the Climate Gap

Rock Dust in Farming: A Potential Strategy to Help Close the Climate Gap

19 February 2018

James Hansen

Today’s governments are wittingly leaving young people with a grinding, growing climate mess.

Delayed response of climate to human-caused rising atmospheric CO2 threatens to leave young people a situation out of their control.  The primary action required to avoid that outcome is rapid reduction of fossil fuel emissions.  However, our “Young People’s Burden” paper[1] shows that more is required: it is also necessary to extract CO2 from the air.

A study led by David Beerling and his group in Sheffield, UK, proposes a change to agricultural practices that could increase the rate of the natural weathering process that removes CO2 from the air.  Logistical infrastructure to apply appropriate (basaltic) rock dust to managed croplands already exists due to the common need to apply crushed limestone to reverse acidification.

Rock dust has potential to improve soil fertility and provide protection against pests and diseases so there is hope that costs could be offset by financial benefits.  If it proves feasible to employ such practices on a large scale an important benefit could be reduction of ocean acidification, which threatens marine biocalcifiers such as corals and shellfish.  Further study and field assessments are needed to verify benefits and address potential obstacles to large-scale adoption.

The papers abstract is given below and a news release is attached.  Media reports are strictly embargoed until 16:00 (GMT) Monday 19 February 2018

 

[1] Hansen, J. et al., Young people’s burden: requirement of negative CO2 emissions, Earth Syst. Dynam 8, 577, 2017.

Farming with crops & rocks.png
University of Sheffield.png

News
Release
Draft

**Strictly embargoed until 16:00 (GMT) Monday 19 February 2018**

Farming crops with rocks to reduce CO2 and improve global food security

·       Enhanced rock weathering involves adding minute rock grains to cropland soils which dissolve chemically taking up carbon dioxide and releasing plant essential nutrients.

·       Unlike other carbon removal strategies enhanced rock weathering doesn’t compete for land used to grow food or increase the demand for freshwater.

·       Other potential benefits include reducing the use of agricultural fertilizers and pesticides, lowering the cost of food production and increasing farm profitability.

Farming crops with crushed rocks could help to improve global food security and capture CO2 from the atmosphere, a new study has found.

The pioneering research by scientists at the University of Sheffield together with international colleagues suggests that adding fast-reacting silicate rocks to croplands could capture CO2 and give increased protection from pests and diseases while restoring soil structure and fertility.

Professor David Beerling, Director of the Leverhulme Centre for Climate Change Mitigation at the University of Sheffield and lead author of the research, said: “Human societies have long known that volcanic plains are fertile, ideal places for growing crops without adverse human health effects, but until now there has been little consideration for how adding further rocks to soils might capture carbon.

“This study could transform how we think about managing our croplands for climate, food and soil security. It helps move the debate forward for an under-researched strategy of CO2 removal from the atmosphere - enhanced rock weathering - and highlights supplementary benefits for food and soils.

“The magnitude of future climate change could be moderated by immediately reducing the amount of CO2 entering the atmosphere as a result of burning fossil fuels for energy generation. Adopting strategies like this new research that actively remove CO2 from the atmosphere would contribute this effort and could be adopted rapidly.”

The research, published today (19 February 2018) in Nature Plants, examined the approach which involves amending soils with abundant crushed silicate rocks, like basalt, left over from ancient volcanic eruptions. As these minute rock grains dissolve chemically in soils, they take up carbon dioxide and release plant-essential nutrients.

Critically, enhanced rock weathering works together with existing managed croplands.  Unlike other carbon removal strategies being considered, it doesn’t compete for land used to grow food or increase the demand for freshwater. Other benefits include reducing the usage of agricultural fertilizers and pesticides, lowering the cost of food production, increasing the profitability of farms and reducing the barriers to uptake by the agricultural sector.

Crushed silicate rocks could be applied to any soils, but arable land is the most obvious because it is worked and planted annually.  It covers some 12 million square kilometres or 11 per cent of the global land area. 

Arable farms already apply crushed rock in the form of limestone to reverse acidification of soils caused by farming practices, including the use of fertilizers.  Managed croplands, therefore, have the logistical infrastructure, such as the road networks and machinery, needed to undertake this approach at scale.  These considerations could make it straight forward to adopt.

Professor  Stephen Long at the University of Illinois Champaign-Urbana, and co-author of the study added: “Our proposal is that changing the type of rock, and increasing the application rate, would do the same job as applying crushed limestone but help capture CO2 from the atmosphere, storing it in soils and eventually the oceans.

“Global warming is a problem that affects everyone on the planet.  Scientists generally have done a poor job of getting across the point that the world must reduce emissions of greenhouse gases from fossil fuels and combine this with strategies for extracting carbon dioxide from the atmosphere to avoid a climate catastrophe. 

Professor James Hansen from the Earth Institute at Columbia University and co-author of the work, added: “Strategies for taking CO2 out of the atmosphere are now on the research agenda and we need realistic assessment of these strategies, what they might be able to deliver, and what the challenges are.” 

The video below from the Leverhulme Centre for Climate Change Mitigation highlights the approach.

https://www.youtube.com/watch?v=G1WZloWgpAw

Ends                                                         

For further information please contact: Amy Huxtable, Media Relations Officer, University of Sheffield, 0114 222 9859

Notes to editors

The Leverhulme Centre for Climate Change Mitigation is funded with an award of £10 million over 10 years from the Leverhulme Trust and includes UK partner institutes (University of Sheffield, University of Southampton, University of Cardiff and the Open University) and international partners (University of Illinois at Champaign-Urbana, James Cook University, University of California – Riverside, and the South East Asian Rainforest Programme).

The Leverhulme Trust was established by the Will of William Hesketh Lever, the founder of Lever Brothers.  Since 1925 they have provided grants and scholarships for research and education; today, we are one of the largest all-subject providers of research funding in the UK, distributing approximately £80m a year.

The Department of Animal and Plant Sciences
The Department of Animal and Plant Sciences at the University of Sheffield is home to one of the biggest communities of whole-organism biologists in the UK. Their research covers animals, plants, humans, microbes, evolution and ecosystems, in habitats ranging from the polar regions to the tropics. This work aims to shed new light on the fundamental processes that drive biological systems and help solve pressing environmental problems. Researchers and students work closely with organisations ranging from the UK Environment Agency and the Royal Horticultural Society, to Heineken and Shell, with every student given the opportunity go on an optional field course between second and third year to habitats ranging from the Peak District to Tanzania. Second year students are also given the chance to make wildlife documentaries with the help of BBC film makers. Find out more at www.sheffield.ac.uk/aps.

The University of Sheffield

With almost 29,000 of the brightest students from over 140 countries, learning alongside over 1,200 of the best academics from across the globe, the University of Sheffield is one of the world’s leading universities.

A member of the UK’s prestigious Russell Group of leading research-led institutions, Sheffield offers world-class teaching and research excellence across a wide range of disciplines.

Unified by the power of discovery and understanding, staff and students at the university are committed to finding new ways to transform the world we live in.

Sheffield is the only university to feature in The Sunday Times 100 Best Not-For-Profit Organisations to Work For 2017 and was voted number one university in the UK for Student Satisfaction by Times Higher Education in 2014. In the last decade it has won four Queen’s Anniversary Prizes in recognition of the outstanding contribution to the United Kingdom’s intellectual, economic, cultural and social life.

Sheffield has six Nobel Prize winners among former staff and students and its alumni go on to hold positions of great responsibility and influence all over the world, making significant contributions in their chosen fields.

Global research partners and clients include Boeing, Rolls-Royce, Unilever, AstraZeneca, Glaxo SmithKline, Siemens and Airbus, as well as many UK and overseas government agencies and charitable foundations.

To read other news releases about the University of Sheffield, visit http://www.shef.ac.uk/news  

 

 

North Dakota Sentence

North Dakota Sentence

6 February 2018

James Hansen

Michael Foster (see How Does It Feel) was sentenced today to three years imprisonment with all but 360 days suspended, after his conviction (see North Dakota Conviction) on three of four counts, two felonies and one misdemeanor. 

Judge Fontaine ruled out use of the “necessity” defense prior to the trial, and she also would not allow me to inform the jury about factors affecting Foster’s state of mind and his action.  However, I subsequently presented the Judge a letter pleading for leniency in his sentencing and an expert report explaining the urgency of actions to phase out fossil fuel emissions.

The letter to Judge Fontaine and How Does It Feel are my summaries of the situation and its larger context.  If I had to put it in one sentence, it might be: the older generations, the people in power, are failing to protect the rights and the future of young people. 

Frankly, I do not see how we can fix the situation without making America America again. 

Young people will need to provide the leadership to achieve that.  The best that older people who care can do is make clear what we have learned.  That is what I am trying to do in “Sophie’s Planet.”  I am making good progress, but need a little longer to finish it.

Global Temperature in 2017

Global Temperature in 2017

18 January 2018

James Hansen[a], Makiko Sato[a], Reto Ruedy[b,c], Gavin A. Schmidt[c], Ken Lo[b,c], Avi Persin[b,c]

 

Abstract.  Global surface temperature in 2017 was the second highest in the period of instrumental measurements in the Goddard Institute for Space Studies (GISS) analysis.  Relative to average temperature for 1880-1920, which we take as an appropriate estimate of “pre-industrial” temperature, 2017 was +1.17°C (~2.1°F) warmer than in the 1880-1920 base period.  The high 2017 temperature, unlike the record 2016 temperature, was obtained without any boost from tropical El Niño warming.

Update of the GISS (Goddard Institute for Space Studies) global temperature analysis (GISTEMP)[1],[2](Fig. 1), finds 2017 to be the second warmest year in the instrumental record.  (More detail is available at http://data.giss.nasa.gov/gistemp/ and http://www.columbia.edu/~mhs119/Temperature; figures here are available from Makiko Sato on the latter web site.)  A few figures are included below as an appendix.

We take 1880-1920 as baseline, i.e., as the zero-point for temperature anomalies, because it is the earliest period with substantial global coverage of instrumental measurements and because it also has a global mean temperature that should approximate “preindustrial” temperature[3].

      We estimate current underlying temperature, excluding short-term variability via linear fit to the post-1970 temperature (Fig. 1).  The result is +1.07°C at the beginning of 2018 relative to 1880-1920.

      Figure 2 compares maps of global temperature anomalies of the past three years.  The map in the lower right is the difference between 2017 and 2015 temperatures, revealing that 2017 was notably warmer than 2015 in the polar regions.  This 2017-2015 difference map suggests the reason why some temperature analyses report 2017 as the third warmest year, behind 2015 as well as 2016.  Some analyses include only area close to the points of actual observations in their ‘global’ analysis.  The GISS analysis[1] extrapolates observations as far as 1200 km from measurement points, thus covering practically the entire globe.  It has been shown, by sampling globally complete data with realistic temporal and spatial variability, that this extrapolation procedure yields a more accurate estimate of annual global temperature than global integration methods that restrict the area to regions very close to observed points.[4],[1]

   Fig. 1.    (a) Global surface temperatures relative to 1880-1920 based on GISTEMP data, which employs GHCN.v3 for meteorological stations, NOAA ERSST.v5 for sea surface temperature, and Antarctic research station data[1].

Fig. 1. (a) Global surface temperatures relative to 1880-1920 based on GISTEMP data, which employs GHCN.v3 for meteorological stations, NOAA ERSST.v5 for sea surface temperature, and Antarctic research station data[1].

   Fig. 2.    Temperature anomalies in 2017, 2016 and 2015 relative to 1951-1980 base period.&nbsp; The lower right map shows the difference between the 2017 and 2015 maps.&nbsp; We use the 1951-1980 base period for maps because of more limited global data coverage in 1880-1920.

Fig. 2. Temperature anomalies in 2017, 2016 and 2015 relative to 1951-1980 base period.  The lower right map shows the difference between the 2017 and 2015 maps.  We use the 1951-1980 base period for maps because of more limited global data coverage in 1880-1920.

Figure 3 compares the GISS analysis of global temperature change with the case in which the polar regions, specifically regions poleward of 64 degrees latitude, are excluded from the analysis.  With polar regions excluded, 2017 becomes the third warmest year, and the ‘global’ warming relative to the base period is reduced by almost a tenth of a degree Celsius.  We do not mean to imply that other analyses entirely exclude polar regions.  Therefore we make a more specific test of the impact of omitted regions by carrying out the GISS analysis with local measurements extrapolated only 250 km rather than 1200 km.  Fig. A2 shows that this area limit also causes 2017 to be only the third warmest year.

      We conclude that 2017 probably was the second warmest year.  However, the temperatures of 2015 and 2017 are so close that the difference is unimportant.

      Prospects for continued global temperature change are more interesting and important.  The record 2016 temperature was abetted by the effects of both a strong El Niño and maximum warming from the solar irradiance cycle (Fig. 4).  Because of the ocean thermal inertia and decadal irradiance change, the peak warming and cooling effects of solar maximum and minimum are delayed about two years after irradiance extrema.  The amplitude of the solar irradiance variation is smaller than the planetary energy

   Fig. 3.    Global temperature compared with the result for integration over the region from 64°N to 64°S, which covers 90% of Earth’s surface, excluding only polar regions.

Fig. 3. Global temperature compared with the result for integration over the region from 64°N to 64°S, which covers 90% of Earth’s surface, excluding only polar regions.

  Fig. 4. &nbsp; Solar irradiance and sunspot number in the era of satellite data.&nbsp; Left scale is the energy passing through an area perpendicular to Sun-Earth line.&nbsp; Averaged over Earth’s surface the absorbed solar energy is ~240 W/m2, so the full amplitude of the measured solar variability is ~0.25 W/m2.

Fig. 4.  Solar irradiance and sunspot number in the era of satellite data.  Left scale is the energy passing through an area perpendicular to Sun-Earth line.  Averaged over Earth’s surface the absorbed solar energy is ~240 W/m2, so the full amplitude of the measured solar variability is ~0.25 W/m2.

imbalance, which has grown to about +0.75 ± 0.25 W/m2 over the past several decades due to increasing atmospheric greenhouse gases.[5],[6] However, the solar variability is not negligible in comparison with the energy imbalance that drives global temperature change.  Therefore, because of the combination of the strong 2016 El Niño and the phase of the solar cycle, it is plausible, if not likely, that the next 10 years of global temperature change will leave an impression of a ‘global warming hiatus’.

      On the other hand, the 2017 global temperature remains stubbornly high, well above the trend line (Fig. 1), despite cooler than average temperature in the tropical Pacific Niño 3.4 region (Fig. 5), which usually provides an indication of the tropical Pacific effect on global temperature.[7]  Conceivably this continued temperature excursion above the trend line is not a statistical fluke, but rather is associated with climate forcings and/or feedbacks.  The growth rate of greenhouse gas climate forcing has accelerated in the past decade.[3]  There is also concern that polar climate feedbacks may accelerate.[8]

      Therefore, temperature change during even the next few years is of interest, to determine whether a significant excursion above the trend line is underway.

 

  Fig. 5. &nbsp;  Ni  ñ  o 3.4 and global temperature change during the past five years.

Fig. 5.  Niño 3.4 and global temperature change during the past five years.

Appendix

   Fig. A1.   &nbsp; Global surface temperature relative to 1880-1920 based on GISTEMP data.&nbsp; (a) Annual and 5-year means since 1880, (b) 12- and 132-month running means since 1970.&nbsp; Blue squares in (b) are calendar year (Jan-Dec) means used to construct (a).&nbsp; Update of Fig. 2 in reference 3.

Fig. A1.  Global surface temperature relative to 1880-1920 based on GISTEMP data.  (a) Annual and 5-year means since 1880, (b) 12- and 132-month running means since 1970.  Blue squares in (b) are calendar year (Jan-Dec) means used to construct (a).  Update of Fig. 2 in reference 3.

  Fig. A2.  &nbsp;Global surface temperature with extrapolation of data limited to 250 km from observations.

Fig. A2.  Global surface temperature with extrapolation of data limited to 250 km from observations.

  Fig. A3. &nbsp; Global temperature in the past 100 and past 50 years based on local linear trends.&nbsp;

Fig. A3.  Global temperature in the past 100 and past 50 years based on local linear trends. 

References

[a] Earth Institute, Columbia University, New York, NY

[b] SciSpace LLC, New York, NY

[c] NASA Goddard Institute for Space Studies, New York, NY

[1] Hansen, J., R. Ruedy, M. Sato, and K. Lo, 2010: Global surface temperature change. Rev. Geophys., 48, RG4004, doi:10.1029/2010RG000345.

[2] The current GISS analysis employs NOAA ERSST.v5 for sea surface temperature, GHCN.v.3.3.0 for meteorological stations, and Antarctic research station data, as described in reference 1.

[3] Hansen, J., M. Sato, P. Kharecha, K. von Schuckmann, D.J. Beerling, J. Cao, S. Marcott, V. Masson-Delmotte, M.J. Prather, E.J. Rohling, J. Shakun, P. Smith, A. Lacis, G. Russell, and R. Ruedy, 2017: Young people's burden: Requirement of negative CO2 emissions. Earth Syst. Dynam., 8, 577-616, doi:10.5194/esd-8-577-2017.

[4] Hansen, J.E., and S. Lebedeff, 1987: Global trends of measured surface air temperature. J. Geophys. Res., 92, 13345-13372, doi:10.1029/JD092iD11p13345.

[5] von Schuckmann, K., M.D. Palmer, K.E. Trenberth, A. Cazenave, D. Chambers, N. Champollion, J. Hansen, S.A. Josey, N. Loeb, P.-P. Mathieu, B. Meyssignac, M. Wild, 2016: An imperative to monitor Earth's energy imbalance Nature Climate Change 6, 138-144, doi:10.1038/nclimate2876.

[6] Hansen, J., M. Sato, P. Kharecha, and K. von Schuckmann, 2011: Earth's energy imbalance and implications. Atmos. Chem. Phys., 11, 13421-13449, doi:10.5194/acp-11-13421-2011.

[7] Philander, S.G., Our Affair with El Niño: How We Transformed an Enchanting Peruvian Current into a Global Climate Hazard, Princeton Univ. Press, Princeton, NJ, 288 pp., 2006.

[8] Sommerkorn, M. and Hassol, S.J., 2009: Arctic Climate Feedbacks: Global Implications, World Wildlife Fund report, 98 pages, based on Sommerkorn M., Hamilton N. (eds.) 2008. Arctic Climate Impact Science – an update since ACIA. http://assets.panda.org/downloads/arctic_climate_impact_science_1.pdf

 

Year-End Statement and Solicitation

Year-End Statement and Solicitation

15 December 2017

James Hansen

Below is the statement that I sent recently to thank people who have supported our Climate Science, Awareness and Solutions program in the Columbia University Earth Institute.

Our paper Young People’s Burden: Requirement of Negative CO2 Emissions published this year makes clear how difficult it will be to stabilize climate.  The battle must be fought on multiple fronts.  On the other hand, as we also note, there is some basis for optimism.

Our most pressing need for support at this time is for our non-profit 501/C3 Climate Science, Awareness and Solutions, Inc. (CSAS Inc.).  CSAS Inc is used to pay, without overhead, our computer and other office expenses, travel, and legal costs.

Here is one legal case (in New Zealand) in which some progress is being made.  I will report on others in upcoming Communications.  I believe that the legal approach will become increasingly important in the future, because the judiciary is relatively independent of fossil fuel interests.  The Guardian did an article on this.

Betsy Taylor is President of CSAS, Inc., I am the Chief Executive Officer, Bill McKibben, Jim Miller and Larry Travis are Board Members, and Jay Halfon is the Secretary and Treasurer.

Donations to CSAS, Inc. can be sent to Jay Halfon, 45 West 36th Street Floor 6, New York, NY 10018, attn. Geoff Boehm.  Alternatively, donations can be made to the newly constructed web page for CSAS, Inc.

Of course we also welcome support of our Columbia University program, Climate Science, Awareness and Solutions, which is also 501/C3.  Donations to the Columbia program should be sent to Gregory Fienhold, The Earth Institute, Hogan Hall, Room 108 2910 Broadway, MC 3277 New York, NY 10025 or made online at http://csas.ei.columbia.edu/support/.

In cooperation with Stuart Scott, Executive Director of United Planet Faith & Science Initiative, I had four press conferences in Bonn, each of them doubling as his half-hour TV program “Climate Matters.”  The videos of these are given below.  He would like to translate them to different languages, via subtitles, e.g., Young People’s Burden has been translated to German (click on the CC on the YouTube video).  German and Spanish translations are underway.  He, stuart.h.scott@gmail.com, would welcome volunteers to translate to other languages.

Note sent in late November to supporters of Climate Science, Awareness and Solutions

This week is a good time to thank everyone who has supported Climate Science, Awareness and Solutions.  I also want to offer encouragement about the prospect that the world may soon turn toward solution of global climate change, despite sober analyses about the difficulty of the task.

On the sober side: Our paper Young People’s Burden: Requirement of Negative CO2 Emissions, completed this year and discussed at the COP-23 meeting in Bonn, shows that growth rates of the human-made factors driving climate change have not slowed – indeed, they have accelerated.  The fundamental fact is: fossil fuels will continue to be burned at a high rate as long as the price of fossil fuels does not include costs to society (air pollution, water pollution, climate change).

Yet I believe the work we are doing is on the right course and may make an important difference.  Our Young People’s Burden paper also shows that emission reduction of 3% per year beginning in 2021 could keep global warming from exceeding 1.5°C.  That is not quite as ambitious as the goal of getting CO2 back to 350 ppm by 2100, the “target” that a group of leading researchers defined a decade ago[1].  However, consequences of 1.5°C warming are surely much less severe than they would be with continued business-as-usual fossil fuel emissions.

We chose 2021 as the start date and a focus on the 3%/year emission reduction scenario, because such timing and rates are consistent with success in the actions outlined below.  Legal actions including appeals require time; 2021 starts the next administration in the United States; 3%/year reduction is achievable globally with even a moderate carbon fee/tax.  Three principal elements in our plan and reasons for optimism that we can turn the corner by 2021:

(1) Citizens Climate Lobby steadfastly moves forward in support of carbon-fee-and-dividend.  Now more than 400 chapters and 90,000 members in the U.S. and growing in other countries, they are beginning to be heard in the House and Senate.  They could impact policies by 2021.  We have promoted this approach since 2007 and are probably CCL’s most successful recruiter.

(2) Our Children’s Trust lawsuit: the 9th Circuit Court of Appeals will hear oral arguments on 11 December re the Trump Administration’s attempt to evade a trial.  They have practically no chance, but the trial date scheduled for February is likely to be delayed a few months.  Given Trump’s energy policies, we have every expectation of winning and forcing a climate plan.

(3) Dan Galpern and I went to COP-23 in Bonn for private discussions with representatives of several nations about possible lawsuits against the “Carbon Majors”, large fossil fuel companies. This approach may be more powerful than “divestment” in pressuring them to become energy companies.  The discussions are sensitive, but we can report on them within several months.

Young People's Burden  https://youtu.be/_shhcGeY1Ao

Making the Carbon Majors Pay for Climate Action  https://youtu.be/vLuWNew3znU

Nuclear Power? Are Renewables Enough?  https://youtu.be/v1f4BKsFrCA

Scientific Reticence  https://youtu.be/S7z61UZoppM

 

[1] Hansen, J., M. Sato, P. Kharecha, D. Beerling, R. Berner, V. Masson-Delmotte, M. Pagani, M. Raymo, D. Royer, and J.C. Zachos: Target atmospheric CO2: Where should humanity aim? Open Atmos. Sci. J., 2, 217-231, 2008.

October Global Temperature Update

October Global Temperature Update

To sign up for our monthly update of global temperature (Maps and Graphs), click here.

Additional figures are on our global temperature web page.

 

Oct2017-620x419.png

Globally October 2017 was the second warmest October since reliable measurements began in 1880, 0.90C warmer than the 1951-1980 mean.  October temperature was +1.18C relative to the 1880-1920 base period, which provides our best estimate of pre-industrial global temperature.  The warmest October was 2015 at +1.08C relative to the 1951-1980 mean.  2016 was the 3rd warmest at +0.89C.  The 2017 January to October 10-month mean is second highest, behind 2016, compared to the first 10 months of other years.

Although a weak La Nina is present, the global mean temperature in October stayed relatively high; polar regions were especially warm.  2017 will likely to be the second warmest year in the record.

Making the Carbon Majors Pay for Climate Action

Making the Carbon Majors Pay for Climate Action

13 November 2017

James Hansen and Dan Galpern

Video of press conference on 7 November 2017 in Bonn, Germany, at COP-23.

See Communication of 07 November for transcript.

Global Climate Justice: Making the Carbon Majors Pay for Climate Action

Global Climate Justice: Making the Carbon Majors Pay for Climate Action

07 November 2017

James Hansen

Given that governments were instituted to serve the interests of the public, when climate change threatens the public it is appropriate that governments take actions to protect their citizens.  Given that COP-23 is officially hosted by small island nations whose existence is threatened by climate change, it is appropriate to raise the issue of global climate justice and the fossil fuel industry.

I have come not to dwell on the growing climate crisis – though this crisis is now more profound than any we have ever faced.  I have come not to dwell on the injustice of climate change – though the enormity of that injustice – to young people and future generations, to indigenous people, to fellow species – cannot be overstated.

I have come to note that greenhouse gas climate forcings are accelerating, not decelerating, and sea level rise and ocean acidification are accelerating.  We confront a mortal threat, now endangering, only at first, the very existence of island and low-lying nations in the Pacific and around the planet.

Accordingly, ambition must be increased and enforced.  No nation should be allowed to exit.  Moreover, the unrequited provisions of the SUVA Declaration, Article 19, must be revived.[1]  Effective action must be undertaken not only to keep temperature rise below 1.5° C but, in my view, to return it to below 1° C  to preserve island nations and global shorelines.

The science is clear.  CO2 is the principal control knob that controls global temperature.  Global warming already drives increasing climate extremes.  Tropical cyclones, typhoons and hurricanes left wakes of devastation in the Pacific between 2013 and 2016 and recently in the Caribbean – and there is worse to come, unless we act with resolve and without further delay.

And delayed response of climate – caused by inertia of the deep ocean and massive ice sheets – means that our actions today may hand young people a climate system out of their control.  Consequences, including loss of island nations and major coastal cities, could be locked in.  Subtropics in summer and the tropics year-round could become unbearable.  Mass migrations could make the planet nearly ungovernable.

______

Churchill once said: “The era of procrastination, of half-measures, of soothing and baffling expedients is coming to its close.  In its place we are entering a period of consequences.”

Today we are well into that period; we are now in danger of being too late.

But consequences still may be limited, and irreversible catastrophes avoided, if emissions are rapidly phased out and if soil and biospheric carbon are restored.[2]

Carbon drawdown – via reforestation, soil sequestration, mangrove restoration and regenerative grazing – can be achieved in many nations.[3],[4]  There are limits on this natural carbon uptake, but also potential methods to increase the rate.[5]

Well-conceived projects – designed for efficacy, additionality and permanency – must be commenced and evaluated worldwide.  In order to stabilize climate, CO2 must be removed from the air.

Funding is required.  As a matter of justice it should be extracted from those who benefitted most from fossil fuel burning — the so-called Carbon Majors.

Recent legal actions for damages[6] – for harm to infrastructure and freshwater supplies – are warranted and may help induce a measure of accountability.  However, even more effective legal action is needed, if we are to be serious about our children’s survival and wellbeing.

Authority for effective action resides in almost every member of this conference – every nation that retains a functioning independent judiciary with authority to assess liability.  Legislators around the world could clarify the law related to liability for climate change,[7] but courts are able now to assert jurisdiction to require fossil fuel polluters to pay their fair share.

Legal scholars have outlined the path forward, and one of them is with me here today.[8]  Domestic judicial systems with independence, integrity and strength must be brought to bear, from the Pacific Island countries to China and the United States.  Where courts retain no direct authority over Carbon Major property, judgments still may be enforced – by courts in which assets are located or the corporation is domiciled. Exercise of jurisdiction by several national judicial systems may be needed, and will help guard against the capture of some of them by vested interests.

Every sovereign retains an interest in this cause.  National and state governments hold our natural resources as public trust assets.  As trustees, their core duty is to protect the assets from damage.  They do so expressly for the benefit of their people, including future generations — not for the exploitation and ruination by a few.[9]

As the Supreme Court of the Philippines observed nearly a quarter century ago, government’s obligation to secure the public’s fundamental right to vital natural resources, including rights to a balanced and healthy ecosystem, these “need not even be written in the Constitution for they are assumed to exist from the inception of mankind.”[10]

In my final minute, I return to the problem of obtaining rapid phasedown of fossil fuel emissions.    Let us not sugarcoat the truth: as long as we allow fossil fuels to be cheap energy, not required to pay their costs to society, we cannot kick our fossil fuel addiction.

In my view, the climate problem will not be solved until one, or preferably both, of the two major emitting nations, the United States and China, provides real leadership, including domestic actions.

An across-the-board (oil, gas, coal) rising carbon fee at domestic mines and ports-of-entry is inescapably required.  A border duty can be placed on products from nations that do not have an equivalent fee, to broaden the initiative and ensure against competitive disadvantage.  Only in this way can near-global honest pricing of fossil fuels be obtained.

So let us abandon half-measures and soothing expedients – caps and offsets, politically compromised targets – which simply will not get the job done.

The period of consequence requires honesty and courage. Nothing less will do.

 

[1] Suva Declaration on Climate Change, Sept. 4, 2015 (available at http://pacificidf.org/wp-content/uploads/2013/06/PACIFIC-ISLAND-DEVELOPMENT-FORUM-SUVA-DECLARATION-ON-CLIMATE-CHANGE.v2.pdf).

[2] Hansen, J., M. Sato, P. Kharecha, K. von Schuckmann, D.J. Beerling, J. Cao, S. Marcott, V. Masson-Delmotte, M.J. Prather, E.J. Rohling, J. Shakun, P. Smith, A. Lacis, G. Russell, and R. Ruedy, 2017: Young people’s burden: requirement of negative CO2 emissions. Earth Syst. Dynam., 8, 577-616, doi:10.5194/esd-8-577-2017.

[3] Bustamante, M., Robledo-Abad, C., Harper, R., Mbow, C., Ravindranath, N.H., Sperling, F., Haberl, H., de Siqueira Pinto, A. and Smith, P.: Co-benefits, trade-offs, barriers and policies for greenhouse gas mitigation in the Agriculture, Forestry and Other Land Use (AFOLU) sector, Global Change Biology, 20, 3270–3290, doi: 10.1111/gcb.12591, 2014.

[4] Smith, P.: Soil carbon sequestration and biochar as negative emission technologies, Global Change Biology, 22, 1315-1324, 2016.

[5] Taylor, L.L., J. Quirk, R.M.S. Thorley, P.A. Kharecha, J. Hansen, A. Ridgwell, M.R. Lomas, S.A. Banwart, D.J. Beerling, 2016: Enhanced weathering strategies for stabilizing climate and averting ocean acidification. Nature Climate Change, 6, 402-406. doi:10.1038/nclimate2882.

[6] See, for example, County of Marin et. al, v. Chevron Corp., et. al, Case. No. C17-01227, Marin County, California, Superior Court (July 17, 2017) available at https://www.sheredling.com/wp-content/uploads/2017/07/2017-07-17-MARIN-CO-Sea-Level-Rise-Complaint-5bFINAL-ENDORSED5d.pdf.

[7] See, for example, Andrew Gage and Margaretha Wewerinke, Taking Climate Justice into Our Own Hands: a Model Climate Compensation Act (Vanuatu Environmental Law Association & West Coast Environmental Law 2015).

[8] See, for example, Wood M.C. and D. Galpern, 2015: Atmospheric recovery litigation: making the fossil fuel industry pay to restore a viable climate system, Environ. Law, 45(2), 259-337. ISSN 0046-2276.

[9] See, for example, Massachusetts v EPA 549 US SC 497 (2007) 14 and Georgia v Tennessee Copper Co. 206 US SC 230 (1907).

[10] Juan Antonio Oposa v. Fulgenio S. Factoran, G.R. No. 101083, 224 S.C.R.A. 792 (July 30, 1993).

Young People’s Burden: Averting Climate Disaster*

Young People’s Burden: Averting Climate Disaster*

06 November 2017

Sophie Kivlehan and James Hansen

  1. I’m Sophie Kivlehan from Pennsylvania, the United States. I will first show a few minutes of a speech given by 12-year-old Severn Cullis-Suzuki 25 years ago at the 1st Rio Earth Summit.  A plea to adults to take actions to avoid dangerous climate change.

Then my grandfather and I will take an objective look at the response of the world to her plea.

I will make my own plea to today’s adults, but I will argue that young people must do more than plea, we must demand our rights.

  1. 2.5 Minute Video of Severn’s talk (Powerpoints including video available on JEH website)
  2. Sophie: Yes, make your actions reflect your words.

Have actions reflected the words?  The promise to avoid dangerous climate change?

Sophie: Fig. A1.  Let’s look at the data.  All nations agreed to the Kyoto Protocol in 1997.

In the 25 years leading up to the 1997 Kyoto Protocol emissions increased 1.5 percent per year.

But after 1997 emissions continued to increase – even faster than before!  The graph on the right has a linear scale, so you see easily, the rapid emissions growth.

Jim: Fig. 1.  Emissions from mature economies stabilized.  But they had already stabilized by 1980.  And there is no indication that the 1997 Kyoto Protocol had a substantial effect.

Emissions from the developing world continue to increase as these countries try to raise their standards of living, as they have every right to do.  China’s emissions may be stabilizing now, because they are becoming a mature economy and are trying to limit air pollution from coal.

Sophie: Fig. 2.  Because of these increasing greenhouse gases, global temperature is rising.  Today global temperature is more than 1 degree Celsius warmer than its preindustrial level.

Sophie: Fig. 3.  How high can we let temperature rise?  Our best guide is Earth’s history.

In the Holocene, the past 11,000 years, the period in which civilization developed, maximum temperature was only one-half degree Celsius warmer than preindustrial.

Now temperature is far above the preindustrial Holocene.  It is now close to that in the Eemian period 120,000 years ago, when sea level reached 6-to-9 meters, 20-to-30 feet, higher than today.

Jim: Fig. 8.  Why has temperature increased almost linearly since 1975?  Because Earth is out of energy balance, more energy coming in than going out.  Earth stays out of balance because since 1975 we have kept adding gases that increase climate forcing about 0.04 W/m2 every year.     That will be 4 watts in 100 years, equivalent to doubled CO2, 3°C global warming, enough to guarantee disastrous climate change, loss of all coastal cities.

So IPCC defined a new scenario, RCP2.6 which we have shown is equivalent to reducing emissions 3% per year.  Such reduced emissions limit global warming to 1.5°C, if we also extract, at minimum, 100 GtC from the air via improved agricultural and forestry practices.

Sophie: Climate Forcing.  Now let’s look carefully at what is happening in the real world.

We see that the real world, the top of the red line, is already diverging away from RCP2.6.

Sophie: Climate Forcing Gap.  How important is the gap?  Couldn’t we just extract some CO2 from the air to close the gap?

Sure.  The gap of 0.013 W/m2 is exactly the reduction of climate forcing that occurs if we reduce atmospheric CO2 by 1 part per million.   1 ppm CO2 is 2 GtC, 2 billion tons of carbon.

However, to reduce atmospheric CO2 by 2 GtC, we must extract 4 GtC from the air, because of the equilibrium that exists between atmospheric CO2, ocean CO2 and soil and biosphere CO2.

The cost, at the optimistic rate of $150 per ton of carbon, is $600 billion, but $1.4 trillion at $350/ton.  This cost, about a trillion dollars, is for one year!  And the gap is growing each year!

Adults claim that they are doing something about climate.  But look what a mess they leave for young people!  They are not slowing down the climate freight train by one iota, not by one bit!

As I stand here, 25 years after the first Rio Earth Summit, the words that 12-year-old Severn Cullis-Suzuki spoke should still ring in the ears of government officials. But do our governments really care about her concerns?  Or do they care more about deals with the fossil fuel industry?

Fears expressed by this young girl are coming true.  Species are disappearing.  Coral reefs are bleaching.  Their life is disappearing.  Droughts become stronger and fires are raging, driving refugees and increasing conflict among people.  Storms become stronger and floods more devastating.  Ice sheets are melting.  We debate whether we will lose coastal cities in 150 years, or 100 years or 50 years.  Do adults wonder why young people have increased anxiety today?

Severn spoke directly to the delegates at Rio.  A few of them sat up and took notice.  How long did it affect their conscience?  More important, did it affect their government’s actions?  No.

If I spoke before the delegates today I would feel the same fear and anger that she expressed.  And more, because I can see the hypocrisy of our governments, of our leaders.  In truth, for all their posturing, they have accomplished painfully little to avert the onset of catastrophic climate change.  Money has been shown to be more important than their children’s future.

I am afraid and angry at the problems that greedy and foolish adults have created.  But, just as Severn said, in my anger, I am not blind.  And in my fear, I am not afraid of telling them ALL – diplomats, negotiators, leaders of government, banks and businesses – how I feel.

Adults, you say that you love us.  But I challenge you to make your actions reflect your words.  Without hesitation.  Without consideration of profit.  Instead caring about what is most important – the lives of your children.  If you continue to pursue selfish aims, the result will be enormous suffering by your children.  And no amount of money will save even the wealthiest children. Because money is, at its root, a fiction, and will disappear rapidly in the world you are leading us toward.  I hope that you are listening, and I thank you for letting these words into your heart.

However, I must also say that we young people must not rely only on hopes that you might listen.  Young people are people.  We have rights.  And we can fight for them.

Along with 20 other young people and my grandfather I am a plaintiff in a lawsuit filed by Our Children’s Trust against President Trump and the United States government for violating our Constitutional rights to life, liberty and property.

We still live in a nation of laws.  I believe that our courts will find in our favor and require the government to develop and carry out a plan to reduce fossil fuel emissions.

But will it be too late?  There is such a thing as being too late.

Pipeline.  I encourage more young people to stand up for their rights.  Just a few days ago this group in Minnesota was granted intervenor status, as they fight to stop a new tar sands pipeline.  These young people are standing up to fight on their own, without money, without a lawyer.

Tar Sands.  Meanwhile, what are adults doing?  Making money.  Developing the dirtiest carbon on Earth: tar sands, tar shale, and hydrofracking.  Leaving the mess for young people to clean up.

They even leave us the tab.  A trillion dollars here, a trillion dollars there.  Where can we find it?

We must fight for our rights now, before it is too late.  Thank you for listening and supporting us.

 

*Presentation at COP-23 in Bonn, Germany, 6 November 2017

*Powerpoints available under Presentations at www.columbia.edu/~jeh1

Scientific Reticence: a DRAFT Discussion

Scientific Reticence: a DRAFT Discussion

26 October 2017

James Hansen

I am writing Scientific Reticence and the Fate of Humanity in response to a query from the editor of Atmospheric Chemistry and Physics who handled Ice Melt, Sea Level Rise and Superstorms.[1] That paper, together with Young People’s Burden,[2] makes the case for a low global warming target and the urgency of phasing out fossil fuel emissions.  We argue that global warming of 2°C, or even 1.5°C, is dangerous, because these levels are far above Holocene temperatures and even warmer than best estimates for the Eemian, when sea level reached 6-9 meters (20-30 feet) higher than today.  Earth’s history shows that sea level adjusts to changes in global temperature.  We conclude that eventual sea level rise of several meters could be locked in, if rapid emission reductions do not begin soon, and could occur within 50-150 years with the extraordinary climate forcing of continued “business-as-usual” fossil fuel emissions.

The editor noted that the Ice Melt paper was not highly cited or mainstream in climate impact discussions, and he was concerned because he thought it important for peer-reviewed extreme scenarios to be included in the upcoming IPCC AR6 cycle[3].  It might be added that both papers received VERY extensive peer review, all of which is available on the journals’ web sites.

I responded that I was not surprised by the minimal of citations. A public affairs person handling media contacts for the Ice Melt paper reported that a leading science reporter decided not to write about the paper, and later declined to write about the Burden paper, because 5 of the 6 experts he contacted advised against reporting on it.  If the top people in a field are negative and do not cite a paper, it is license for others to ignore it, perhaps even a warning to younger researchers.

Scientific reticence may play a role here – I should be able to recognize that as well as anyone.  However, my specific interpretation in terms of the famous elephant story is not as obvious.  One would think that top experts in the field should have enough perspective to avoid that malady.  Perhaps they even have a basis that should be presented for believing that a 2°C global warming limit provides a safe guardrail.  It would be good to learn the basis for that in view of all the contrary evidence that we present in the two papers.  Therefore I have written this Scientific Reticence piece as a DRAFT – also because I have not yet given my co-authors on the two papers a change to comment on it — that I plan to revise after getting back from the Bonn COP.

 

Scientific Reticence and the Fate of Humanity

26 October 2017

James Hansen

Frank Dentener, an editor of Atmospheric Chemistry and Physics, in a recent note to me observed that Ice Melt, Sea Level Rise, and Superstorms[4], hereafter Ice Melt, was not highly cited or mainstream in climate impact discussions.  He was concerned because he thought it important for peer-reviewed extreme scenarios to be included in the upcoming IPCC AR6 cycle[5].

In Ice Melt, summarized in a video, we use paleoclimate analyses, climate modeling, and modern observations to expose a global climate emergency: fossil fuel emissions must be reduced as rapidly as practical.  A proposed 2°C global warming target is not a safe “guardrail” – 2°C warming would lock in unconscionable climate impacts on young people and future generations. Earth’s present energy imbalance, with most of the excess energy pouring into the ocean, assures continued ocean warming for decades and threatens to lock in amplifying climate feedbacks, melting of ice shelves and nonlinearly growing sea level rise.  Earth’s energy imbalance also assures continued long-term warming of land areas, with increasingly extreme droughts, floods and storms.  Subtropics in summer and the tropics year-round are becoming uncomfortably warm; these areas will become less habitable if warming continues, increasing immigration pressures and global governance problems.  Responsibility for these affairs will lie with the developed world.  Our related Young People’s Burden[6]  paper shows that continued high fossil fuel emissions unarguably sentences young people to either a massive, implausible cleanup of atmospheric CO2 or growing deleterious impacts or both.

Below I examine whether recent observations support the conclusions in the Ice Melt paper.

First, however, I address “scientific reticence,” which I suspect affects consideration of our Ice Melt and Young People’s Burden papers – more important, it affects public understanding of climate change and the prospects for avoiding disastrous climate impacts.  I once wrote about Scientific Reticence and Sea Level Rise[7] from an academic perspective, concluding, in agreement with Eipper[8], that scientists should not shrink from exercising their rights as citizens and responsibilities as scientists.  Here it may be more informative if I describe two personal examples, papers I published in 1981[9] and 1988[10], each with many co-authors and each with receptions similar to that of the Ice Melt paper.  Those two papers probably had the most impact

  Chart 1.  &nbsp;Abstract of “Climate Impact of Increasing Atmospheric Carbon Dioxide”, by J. Hansen, D. Johnson, A. Lacis, S. Lebedeff, P. Lee, D. Rind, and G. Russell,  Science ,  213 , 957-966, 1981.

Chart 1.  Abstract of “Climate Impact of Increasing Atmospheric Carbon Dioxide”, by J. Hansen, D. Johnson, A. Lacis, S. Lebedeff, P. Lee, D. Rind, and G. Russell, Science, 213, 957-966, 1981.

 

of all papers I have written, yet neither was greeted with citations or approval by the community.  Even after 3-4 decades their cumulative citations rank only #16 and #17 among papers on which I am lead author or co-author.  They rank #11 and #12 among papers on which I am lead author.

  1. 1981 paper: Climate Impact of Increasing Atmospheric Carbon Dioxide

This paper (abstract given in Chart 1), the main product of a 3-year $230K/year pilot grant from NASA, was our first major paper on climate change.  The study showed what could be said based on tools and data available almost 40 years ago, specifically simple climate models, temperatures measured at weather stations, and limited paleoclimate data.

This paper framed an approach to understand the human impact on global climate, asserting that CO2 was the dominant climate forcing, concluding that climate sensitivity was about 2.8°C for doubled CO2, and recognizing that slow feedbacks of ice sheet changes and long-lived greenhouse gases (GHGs) would amplify the long-term climate response.  We found that weather station data provided a good estimate of global temperature change, despite limited coverage in the Southern Hemisphere, and we showed that observed warming of 0.4°C from 1880 to 1979 was consistent with climate simulations for the estimated climate sensitivity.

We made testable predictions: the 1980s were likely to be the warmest decade on record.  Global warming would rise out of the noise level (natural variability) in the 1990s.  The 21st century would see shifting of climate zones, increasing climate extremes including stronger droughts, eroding of ice sheets with rising sea levels, and opening of the fabled Northwest Passage.  Observations have since confirmed those predictions.

We inferred implications for energy use.  We concluded, based on available fossil fuel reserves and paleoclimate evidence (for the sensitivity of sea level to global temperature change), that all coal could not be burned if we wished to preserve shorelines and coastal cities.

We concluded: “… the degree of warming will depend strongly on the energy growth rate and choice of fuels for the next century.  Thus CO2 effects on climate may make full exploitation of coal resources undesirable.  An appropriate strategy may be to encourage energy conservation and develop alternative energy sources while using fossil fuels as necessary during the next few decades.”

This paper in Science received widespread attention, including, front page reporting in the New York Times and lead editorials in the Washington Post and New York Times.  The paper also led to my first testimony to Congress, to a Joint Hearing of two House of Representatives Subcommittees on Carbon Dioxide and the Greenhouse Effect on 25 March 1982.

Scientific criticism and commentary, appropriate for any paper that is pushing the boundaries, was abundant and largely reasonable.  Walter Sullivan, the exceptional science writer for the New York Times, listed a large number of uncertainties noted by Steve Schneider and then dryly stated “These uncertainties are, to a large extent, recognized in the new report, signed by Dr. James Hansen and six colleagues at the space studies institute.”[11]

Criticisms submitted to journals and eventually published included one by S.I. Rasool[12] that lists a large number of uncertainties and then asks, given those, how can we make any prediction of climate change?  The short answer is to recognize the forest for the trees, specifically to realize that CO2 is the dominant climate forcing, that we have sound estimates of global climate sensitivity, and there is substantial offset among the weaker forcings.

But Rasool provided his own answer9: “I guess the answer lies in the fact that some of us feel compelled to emphasize the worst case in order to get the attention of decision makers who control the funding.”  Our response[13] was: “As scientists we did our best to present an unbiased projection of likely climatic effects of CO2.  We also fulfilled what we believe is a responsibility of scientists: to point out clearly the consequences of their findings.”

Less ad hominem criticism was published in Science[14], but it also failed to distinguish the big picture from details.  This published criticism also asserted that temperature observations contradicted the principal sub-global prediction of climate models: that temperature changes should be magnified in polar regions.  In fact, as we showed in our response,[15] the data confirm the predicted enhancement of Arctic warming over the global mean.  Nevertheless, these criticisms were cited by Department of Energy (DoE) program managers, who decided to renege on their promise to continue the $230K/year funding for our CO2/climate research program when responsibility for the CO2/climate program was assigned to DoE.

Funding decisions for other researchers, I noted, sent a clear message: funding prospects were brighter if one emphasized that the science was very uncertain and that much more research was needed before it might be possible to draw inferences related to policy.  Concern about policy implications varies depending upon which political party is in power, but desire to avoid this landmine is one of several factors that encourage scientific reticence.4

Events related to our 1988 paper (citation rank #16), and congressional testimony based on that paper, provide even clearer empirical evidence for scientific reticence about climate change.

 

  1. 1988 paper: Global Climate Changes as Forecast by Goddard Institute for Space Studies Three-Dimensional Model6

This paper provided much of the basis for testimony I gave to the U. S. Senate on 23 June 1988.  My conclusion that greenhouse gases were already having a significant effect on global climate did not meet with universal acclamation.  The reaction was captured well by Richard Kerr’s article Hansen vs. the World on the Greenhouse Threat,[16] as I will discuss.

By 1988 we had temperature data for almost one additional decade beyond the data used for our 1981 paper, which used temperature data through 1978.  By 1988 we had set up near-real-time data processing, updating the global temperature record every month.  The data revealed that the 1980s would easily be the warmest decade in the period of instrumental data that began in 1880, confirming one of the predictions in the 1981 paper.  Also the first five months of 1988 were so warm that I could state that 1988 was likely to be the single warmest year in the entire record.

By 1988 my colleagues at the Goddard Institute and I also had completed a study Climate Sensitivity: Analysis of Feedback Mechanisms[17] that illuminated the roles of fast and slow feedback processes in determining climate sensitivity and climate response time.  The paleo analysis confirmed the high climate sensitivity obtained in models incorporating only fast feedbacks, and it showed that slow feedbacks further amplify long-term climate response.[18]

By 1988 atmospheric CO2 had reached 350 ppm, at least 25 percent above its preindustrial level.  And other GHGs, especially CH4, N2O, and chlorofluorocarbons were adding almost as much radiative forcing as CO2[19] making the GHG radiative forcing equivalent to almost 400 ppm CO2.  This human-made change, most of it achieved within the preceding few decades, was as great as that associated with the climate change from a deep ice age to an interglacial warm period.

To understand the implications of these facts we must use all the tools in our toolbox.  Important tools include (1) insights based on knowledge of Earth’s climate history, (2) climate models, and (3) observations of climate change during the modern era of instrumental measurements.

  Chart 2.  (a) Greenhouse gas scenarios in 1988 GCM simulations, (b) Observed temperature compared with simulations for scenarios A, B, C.&nbsp; Shaded range was based on estimated global temperature at peaks of the current and prior interglacial periods, about 6,000 and 120,000 years ago.

Chart 2. (a) Greenhouse gas scenarios in 1988 GCM simulations, (b) Observed temperature compared with simulations for scenarios A, B, C.  Shaded range was based on estimated global temperature at peaks of the current and prior interglacial periods, about 6,000 and 120,000 years ago.

Kerr’s Hansen vs. the World article illustrates what I mean. A mathematician looks at a series of global temperatures and concludes that they do not prove human-made warming with high confidence. A climate modeler says many processes in the models are not simulated well, so results are unreliable. They are correct that conclusions based on a single approach are limited.  However, it is like the proverbial blind-folded men, each feeling a different part of the elephant.  No one of them, by himself, can determine the nature of the beast.  If they pooled their data they might figure it out, but the committee approach is a tortuous process.  Success is limited by the weakest member, and the process is slow.  That is why you cannot do good multidisciplinary science simply by putting scientists from different disciplines into the same building.  You do good science by putting the information from multiple disciplines into the same brain.

I am not saying that I was the only one who understood in the late 1980s that the world was getting warmer because of the extraordinary human-caused change of atmospheric composition.  On the contrary, one of the scientists interviewed by Kerr said “if there were a secret ballot at this meeting on the question, most people would say that the greenhouse warming is probably there.”  Another said “What bothers a lot of us is that we have a scientist telling Congress things that we are reluctant to say ourselves.”

That is scientific reticence.  It needs to be understood, because the same thing is happening now.  But now the stakes are much higher, and the urgency of cutting through reticence is greater.

However, before describing today’s situation, let’s try to learn something from the 1988 paper.  Predictions in our 1981 paper proved to be accurate, but what about the 1988 climate paper?

We made calculations with a 3-D global climate model (GCM) including a simple representation of the ocean with diffusive mixing of heat anomalies into the deep ocean and specified horizontal ocean heat transport.  The model had coarse spatial resolution, because of our limited computer resources.[20]  The GCM climate simulations in the 1988 paper had horizontal resolution 4 degrees latitude and 5 degrees longitude, coarse enough that we could complete simulations for 1958-2020 for three GHG scenarios in about one-year, running the model as the background job on the computer so that it soaked up all available time, mainly overnight and weekends.

We made climate simulations for three GHG scenarios: (A) continued rapid growth of the annual increment of GHGs, similar to growth from 1950 to early 1980s, (B) constant annual increment of GHGs, (C) stabilization of atmospheric GHG amounts beginning in 2000.  We suggested that scenario B, with approximately constant annual increases of the GHG climate forcing, was the most plausible, with scenarios A and C marking an extreme range of possibilities.[21]  Real world GHG climate forcing turned out to be very close to scenario B (Chart 2a).[22]

Observed global temperature increased after 1988, rising far out of the natural variability range.  Global temperature is now far above the warmest preindustrial time in the Holocene (the current interglacial period, now more than 10,000 years long, during which civilization developed) and approximately matches the peak temperature of the Eemian period (about 120,000 years ago).3  The real world warmed somewhat slower than the model reaching temperature anomaly +1°C about 5 years later than the model.  The greater warming in the model is well accounted for by the fact that the model’s sensitivity was 4.2°C for 2×CO2 (i.e., for doubled CO2, which is a forcing of 4 W/m2), while paleoclimate data and known climate feedbacks suggest that actual (fast feedback) climate sensitivity is close to 3°C for 2×CO2.  We understood that the model’s sensitivity was near the upper end of the accepted range (3±1.5°C for 2×CO2), but unlike the 1-D model used in our 1981 paper, we could not simply adjust the sensitivity to match best knowledge of climate sensitivity.[23]  We could only afford one set of model runs with this first version of our 3-D model, but in interpreting the model runs we can bear in mind the model’s high sensitivity.  Subsequent simulations with newer versions of our model with sensitivity near 3°C for 2×CO2 and simulations by dozens of other modeling groups reported by IPCC[24] confirm good agreement of modeled and observed global temperature change.

 

  Chart 3.  Surface air temperature (°C) simulated with rapidly increasing GHGs and rapidly increasing freshwater discharge from Greenland and Antarctica (Fig. 16 of reference 1).

Chart 3. Surface air temperature (°C) simulated with rapidly increasing GHGs and rapidly increasing freshwater discharge from Greenland and Antarctica (Fig. 16 of reference 1).

  1. Ice Melt paper

In 2007-8 we made climate simulations driven by GHG scenario[25] A1B plus rapidly growing ice and fresh water discharge from Antarctica and Greenland.  The 4°×5° climate model found cooling southeast of Greenland and around Antarctica associated with reduced deep water formation in the North Atlantic and reduced bottom water formation around Antarctica.  We traced surface cooling and reduced ocean overturning in part to cooling from melting ice but mainly to the buoyancy effect of the added fresh water in upper ocean layers.

As discussed in Section 2 (Background Information) of our Ice Melt paper, I was interested in the potential relation of these effects to evidence that Paul Hearty found for rapid sea level rise and North Atlantic storminess late in the Eemian interglacial period.  These initial simulations affected interpretations in my book, Storms of My Grandchildren,[26] but we did not begin to write a paper on the climate simulations until several years later, by which time improvements had been made in the ocean model, as described in Section 3 of the Ice Melt paper.

Thus we repeated the fresh water discharge experiments with the newer model, again finding surface cooling (Chart 3) and subsurface ocean warming similar to that in the older model.  The subsurface warming occurs at depths where it can melt the underside of ice shelves, the tongues of ice extending from ice sheets into the ocean, especially at the depths of their grounding lines.  This subsurface warming helps explain ice shelf retreat, ice sheet disintegration and sea level rise in paleoclimate data (Shaffer et al., 2004[27]; Petersen et al., 2013[28]).

  Chart 4.  Stratification and precipitation feedbacks. Stratification: increased freshwater flux reduces surface water density, thus reducing AABW formation, trapping NADW heat, increasing ice shelf melt. Precipitation: freshwater flux cools the ocean mixed layer, increases sea ice area, causing precipitation to fall before it reaches Antarctica, reducing ice sheet growth and increasing ocean surface freshening.

Chart 4. Stratification and precipitation feedbacks. Stratification: increased freshwater flux reduces surface water density, thus reducing AABW formation, trapping NADW heat, increasing ice shelf melt. Precipitation: freshwater flux cools the ocean mixed layer, increases sea ice area, causing precipitation to fall before it reaches Antarctica, reducing ice sheet growth and increasing ocean surface freshening.

We showed that freshwater injection increases the planetary energy imbalance, increasing heat flux into the ocean.  This process is thus an amplifying feedback, as accelerating ice melt places a lid on the polar ocean that limits heat loss to the atmosphere and space.  Polar ocean cooling at the sea surface tends to prevent sea ice from receding in a warming world, or may even cause an expansion of sea ice area.  This is an additional amplifying feedback on ice sheet mass balance and sea level rise, because it reduces snowfall on the ice sheets (Chart 4).

We concluded, based on evidence from modeling (our model and others in the literature), paleoclimate analyses, and ongoing observed changes in both polar regions, that the overturning ocean circulations are more sensitive to freshwater injection than models have suggested.[29]  We argued that slowdown of the Atlantic Meridional Overturning Circulation (AMOC) and the Southern Meridional Overturning Circulation (SMOC) are already underway as a result of increased injection of freshwater into the North Atlantic and Southern Oceans.  In the North Atlantic the increased freshwater is from Greenland and small ice cap meltwater and increased precipitation.  In the Southern Ocean the increased freshwater is mainly from increased ice shelf mass loss and increased precipitation.

It is important to confirm whether freshwater injection caused by global warming is already slowing the AMOC and SMOC.  Slowdown of the SMOC would be a substantial amplifying feedback that increases subsurface ocean warming, ice shelf melt, and eventual sea level rise.

  Chart 5.  Temperature anomaly pattern associated with the Pacific Decadal Oscillation, similar to El Niño (source: &nbsp; https://www.google.com/search?q=map+of+pacific+decadal+oscillation+sst+pattern&amp;rlz=1C1CHBD_enUS765US766&amp;tbm=isch&amp;  tbo=u&amp;source=univ&amp;sa=X&amp;ved=0ahUKEwiLgrjGs4TXAhUFyyYKHUorDboQ7AkIQQ&amp;biw=850&amp;bih=714#imgrc=zMTNaBU5EgwHmM:)

Chart 5. Temperature anomaly pattern associated with the Pacific Decadal Oscillation, similar to El Niño (source:  https://www.google.com/search?q=map+of+pacific+decadal+oscillation+sst+pattern&rlz=1C1CHBD_enUS765US766&tbm=isch& tbo=u&source=univ&sa=X&ved=0ahUKEwiLgrjGs4TXAhUFyyYKHUorDboQ7AkIQQ&biw=850&bih=714#imgrc=zMTNaBU5EgwHmM:)

In the Ice Melt paper we showed that, despite global warming, observed sea surface temperature (SST) in the West Antarctic region was declining in the real world, even faster than in the model, and Southern Hemisphere sea ice was increasing (Figs. 31 and 32 in Ice Melt).  Since publication of the paper there has been at least a temporary change in these tendencies, coinciding with a strong El Niño and rapid global warming.  This change is consistent with El Niño conditions, as the SST anomalies associated with El Niño or the positive phase of the Pacific Decadal Oscillation (PDO) have warming in the West Antarctic region (Chart 5).

Chart 6 updates Fig. 31 of Ice Melt to include 2016 data.  The added year is warmer than the prior several years, yet considerably cooler than the years affected by the 1997-98 El Niño.  Chart 7 updates Fig. 32 of Ice Melt, revealing a large 2016 decrease of Southern Hemisphere sea ice area, to a level less than the 1979-2000 base period average (Chart 7).

  Chart 6.  Update of Fig. 31 of  Ice Melt  paper; 2016 temperature has been added.

Chart 6. Update of Fig. 31 of Ice Melt paper; 2016 temperature has been added.

  Chart 7.  Update of Fig. 32 of  Ice Melt  paper; 2016 sea ice data are added in part (b).

Chart 7. Update of Fig. 32 of Ice Melt paper; 2016 sea ice data are added in part (b).

  Chart 8.  Update of Fig. 30 of  Ice Melt  paper.&nbsp; The JPL Wiese et al. data extend through 22 January 2017.

Chart 8. Update of Fig. 30 of Ice Melt paper.  The JPL Wiese et al. data extend through 22 January 2017.

To clarify the issue: global warming nominally would cause global SST to increase and sea ice area to decrease, but we asserted in Ice Melt that in the Southern Ocean there are feedbacks (Chart 4) that oppose those trends and that these feedbacks can even cause Southern Ocean (ocean surface) cooling and sea ice expansion.  Evidence of Southern Ocean cooling is weakened by 2016 data, but this reversal is of the sense expected due to the recent strong El Niño and global warming.  It is our expectation that there will be a rebound of Southern Ocean sea ice area during the next few years as freshwater injection increases.

We can learn more about these feedbacks, and about the ultimate quantity of interest, sea level change, by examining time dependent data on ice sheet mass changes.  Fresh water from increasing ice sheet mass loss is the principal drive that spurs the feedbacks in Chart 4.

Chart 8 updates ice sheet mass change of the Greenland and Antarctic ice sheets, with gravity satellite data providing data since 2002.  The large interannual variations in ice sheet mass change rate, especially in Antarctica, are real as indicated by good agreement of satellite (GRACE) data and analyses based on surface mass balance.[30]  Surface mass balance is calculated as snowfall minus ablation (based on regional atmospheric models) minus perimeter ice loss (calculated from glacier velocities and ice thickness to deduce rate of ice mass change).27

The large interannual variations of Antarctic ice mass change rate are accociated with variable meteorology over the continent, not with discharge of ice from the ice sheet perimeter, which changes more slowly.27  We would like to know whether these interannual fluctuations in the Antarctic ice mass change provide evidence about the feedbacks we describe in Chart 4.  For that purpose we compare in Chart 9 the sea ice area in the Southern Ocean and the annual ice sheet mass change, using satellite data of Chart 8.  The correlation coefficient is 71 percent, consistent with our expectation that greater sea ice area will result in less precipitation over Antarctica.

Our expectation is that Southern Hemisphere sea ice area will increase in the next several years, and the mass change of the Antarctic ice sheet will again be a (growing) loss rate.

Greenland is a very different case, in some ways more complex.  Antarctica presents a greater danger of rapid multi-meter sea level rise, because of expectation that the dominant process

  Chart 9.  12-month running means of Antarctic ice mass change rate and Southern Ocean sea ice area.

Chart 9. 12-month running means of Antarctic ice mass change rate and Southern Ocean sea ice area.

there is ocean melt of ice shelves, speeding up discharge of land ice, especially ice in valleys below sea level with retrograde beds,[31] as well as the fact that there is an order of magnitude more ice in Antarctica.  Slowing of the AMOC leads to cooling of the North Atlantic southeast of Greenland, but overall SSTs on Greenland’s periphery are increasing, which tends to increase snowfall on Greenland.  Chart 10a shows the surface mass balance yesterday, from a Danish web site updated daily.  Chart 10b shows that many heavy snowfalls in the accumulation season and cloudy cool weather in the middle of the melt season led to a surface mass balance +550 Gt in 2016-17.  In contrast, in 2011-12 high pressure over Greenland and winds from the south led to large summer surface melt and an annual surface mass balance of only +50 Gt.  Ice loss at the periphery may cause the Greenland ice sheet to have a net mass loss in 2016-17.

  Chart 10.  Left: surface mass balance (SMB) on 24 October 2017.&nbsp; Right: SMB in past 14 months and cumulative SMB in 3 years.&nbsp; Gray region shows range of all years excluding single most extreme max and min.&nbsp; See: http://www.dmi.dk/en/groenland/maalinger/greenland-ice-sheet-surface-mass-budget/

Chart 10. Left: surface mass balance (SMB) on 24 October 2017.  Right: SMB in past 14 months and cumulative SMB in 3 years.  Gray region shows range of all years excluding single most extreme max and min.  See: http://www.dmi.dk/en/groenland/maalinger/greenland-ice-sheet-surface-mass-budget/

Increased snowfall in recent years makes the variability of the net ice sheet mass loss curves (Chart 8) so large as to discourage use of that graph for an empirical indication of the growth rate of ice loss relevant to future sea level change.  A better measure of the time scale is the warming-induced increase in the discharge rate of land-based ice from the ice sheet perimeter, because that is the quantity that will eventually determine the time scale for sea level rise.  This increment to the peripheral ice discharge rate can be obtained as the difference between the satellite-measured ice sheet mass change and the surface mass balance as defined in Chart 10.  If this increment to the peripheral ice discharge rate has a doubling time as short as 10-20 years, multi-meter sea level rise can be expected in 50-150 years, as concluded in our Ice Melt paper for the case of business-as-usual fossil fuel emissions continue (A1B scenario).  More on this topic later.

  1. Young People’s Burden paper3

In Burden we show that present global temperature is already far above its range during the preindustrial Holocene, i.e., above the levels that existed during the period in which civilization developed.  Indeed, the present global temperature has reached the peak level during the Eemian, the prior interglacial period when sea level reached 6-9 m (20-30 feet) higher than today.

The rapidity of ice sheet and sea level response to global temperature is difficult to predict, but it depends on the magnitude of warming.  Targets for limiting global warming, at minimum, must aim to avoid leaving global temperature at Eemian or higher levels for centuries.  Such targets now require “negative emissions”, i.e., extraction of CO2 from the air.

If phasedown of fossil fuel emissions begins soon, improved agricultural and forestry practices, including reforestation and steps to improve soil fertility and increase its carbon content, may provide much of the necessary CO2 extraction.  In that case, the magnitude and duration of global temperature excursion above the natural range of the current interglacial (Holocene) could be limited and irreversible climate impacts could be minimized.

In contrast, continued high fossil fuel emissions will place a burden on young people to undertake massive technological CO2 extraction if they are to limit climate change and its consequences.  Proposed methods of extraction such as bioenergy with carbon capture and storage (BECCS) or air capture of CO2 have minimal estimated costs of 89-535 trillion dollars this century and also have large risks and uncertain feasibility.

We conclude that continued high fossil fuel emissions unarguably sentences young people to either a massive, implausible cleanup or growing deleterious climate impacts or both.

The Paris Agreement,[32] slowdown of the growth rate of fossil fuel CO2 emissions, and falling prices of renewable energies have contributed to a widespread optimism about progress toward stabilizing climate.  In Burden we show that real world data do not support that optimism.

Chart 11 shows the annual increase of greenhouse gas climate forcing.  The annual change is growing, not decreasing!  That growth continues up to the present.  The figure appears to go only through 2015, because we smooth data to minimize effects of short-term variability, mainly the Southern Oscillation.  The figure is from the EGU video on the Young People’s Burden paper, for which observations of atmospheric gas amounts are updated monthly on our website.

  Chart 11. &nbsp; Greenhouse gas (GHG) climate forcing annual growth rate.&nbsp; IPCC scenario RCP2.6 keeps maximum global warming &lt;1.5°C.&nbsp; Annual addition to future warming (right hand scale) assumes climate sensitivity 3°C for 2×CO2.&nbsp; Actual GHG growth exceeds RCP2.6 by at least 0.01 W/m2 in 2015 and 2016.

Chart 11.  Greenhouse gas (GHG) climate forcing annual growth rate.  IPCC scenario RCP2.6 keeps maximum global warming <1.5°C.  Annual addition to future warming (right hand scale) assumes climate sensitivity 3°C for 2×CO2.  Actual GHG growth exceeds RCP2.6 by at least 0.01 W/m2 in 2015 and 2016.

Why are CO2 and CH4 increasing faster than a decade ago?  Nobody knows for sure, but the increasing rate is not surprising, as discussed in the paper. Slow (amplifying) feedbacks are likely greater with recent global warming. Wetland CH4 emissions seem to have increased; CH4 leaks during fracking may contribute.

The most recent IPCC study (AR5) includes a scenario with declining GHG growth (RCP2.6), which would keep maximum warming near 1.5°C.  However, inclusion of such a scenario does nothing to alter reality (Chart 11).  The gap between reality and RCP2.6 exceeds 0.01 W/m2 in both 2015 and 2016.                 

Failure to reduce emissions as per RCP2.6 in principle can be offset by extracting CO2 from the air.  The 2015 gap, 0.0127 W/m2, can be closed by reducing atmospheric CO2 ~ 1 ppm, requiring extraction of about 3.5 GtC from the air.  Using the optimistic extraction cost estimate[33] of $150-350/tC implies a 2015 cost of $525-$1225B to stay on the 1.5°C (RCP2.6) track.

The gap at present is growing, so the required annual extraction and annual cost can be expected to grow.  Where will that money be found?  It won’t.  The problem and the consequences are being dumped on young people.  See Young People’s Burden paper for further discussion.

Note that both the Ice Melt and Burden papers received extraordinarily detailed peer reviews.

 

 

  1. Discussion: Reticence?

It is conceivable that scientific reticence plays a part in the reactions to our papers, but I am not convinced that it is the whole story.  In the 1981 and 1988/89 examples discussed above there was evidence, in the reviews of those papers and in the published commentaries, that much of the criticism suffered from the “blindfolds and elephant” explanation.  They did not seem to be considering the entirety of information that we had from paleoclimate, modern observations, and models, with recognition of model weaknesses.  However, in current analyses it seems unlikely that recognized experts are not considering the full range of available information.

The Ice Melt paper is long.  One author who does cite Ice Melt immediately dismisses it, because, he claims, the freshwater injection rates (hosing rates, he calls them) are unrealistically large.  Obviously he did not read the paper.  The injection/hosing rates are based on observed data for recent years and projected forward with different time scales for their growth rate (10, 20, 40 year doubling times).  Our conclusion that the AMOC and SMOC are already beginning to slow down is based on current observations and model results in the present and near-term, not on the high rates of freshwater injection that occur after many doublings.  When one such author rejects a paper based on such a misinterpretation, it is easy for the attitude to spread.

Criticism of IPCC.  I chose in 1989, when faced with scientific reticence and more, to bail out of the media circus and focus only on science.  When I reentered the fray in 2004 it was not just to criticize the lack of climate actions by the Bush Administration, but also to draw attention to the need for a low target on global warming if “dangerous” consequences were to be avoided.  Specifically, as spelled out in A Slippery Slope,[34] I criticized the sea level change analysis in the most recent (2001) IPCC report.  IPCC scenarios had GHG amounts and calculated global temperatures that were “off the charts” compared to paleoclimate data covering hundreds of thousands or even millions of years, yet the calculations for the contribution of Greenland and Antarctica to sea level rise was measured in cm, very few cm.  That didn’t seem plausible, as I argued on heuristic grounds, mainly concerned with the role of a warming ocean on ice shelves.

This came across as a criticism of IPCC.  I cited Richard Feynmann insights in Slippery Slope, and more directly in Storms of My Grandchildren,[35] about how the community tends to move slowly in correcting an error.  He is talking about scientific reticence.  However, I probably could have been more discrete in criticizing IPCC – after all, the scientists contributing to those long reports put in a lot of work for very little recognition.

Superstorms and flying boulders.  Several reviews and commentaries seemed angry about the use of the word “superstorms” in the title, even asserting that it was intended to draw public attention to the paper. Duh. What a bad thing to do!  Is this feeling related to scientific reticence?

We were not helped by the Washington Post article referring to flying boulders.  We did not say that any boulders flew.  Our interpretation of the boulders on Eleuthera is that powerful storm-driven late-Eemian waves, when sea level was several meters higher than today, transported the boulders from the cliffs below to their present location where they rest on Eemian substrate.

Recent publications have confirmed that storms can move very large boulders.  The funneling nature of the bay on Eleuthera increases the power of the waves in the vicinity of the boulders.  Boulders in that region moved during the Holocene are smaller, suggesting that some storms in the late Eemian were stronger than today.

None of the major conclusions in our paper, about the threat of large sea level rise or about AMOC and SMOC already slowing down, depend on interpretation of the Eleuthera boulders.  However, I would like to draw attention to a new comprehensive review paper by Hearty and Tormey[36] on the geologic evidence.

Early Discussion of Discussion paper and peer-review.  Both the Ice Melt and Burden papers were submitted to journals that include publication of an initial “Discussion” version of the paper, after it has been checked and approved by an editor.  This publication mode seemed especially appropriate for both papers: there were upcoming United Nations climate conferences and we hoped to get feedback from both scientists on the science and from the public and policymakers on the papers’ policy implications.  However, there was criticism of whether the papers should be discussed publicly before the peer-review process is complete.

Even if there is merit to that position – and I see nothing wrong with presenting a discussion paper for discussion (!) as long as it is so identified – both papers subsequently passed detailed peer-review.  Indeed, the Ice Melt paper seemed to go through further review by an editorial board, which seemed to redefine the word “dangerous” to mean something different than what the public means.  See Dangerous Scientific Reticence.

Negative Emissions.  Perhaps nothing illustrates the dangers of scientific reticence better than the way negative emissions crept into IPCC scenarios.  Clarifying the implausibility of that scenario is an objective of our Burden paper.

Co-authors.  People suggesting that we are exaggerating the global warming threat should take a close look at the list of co-authors.  They include top scientists in the world in the relevant disciplines.  I am grateful to them for all that they have done to help produce the two papers.

I note that I am sending out this draft discussion without showing it to the co-authors, because I need the next week to prepare materials for discussions at the Bonn COP meeting.

In an attempt to make up for any flaws in this draft, I include here a few cartoons to lighten the mood – even God and Noah have a sense of humor.  Any suggestions re this reticence topic would be most welcome.

 

 David Horsey, Los Angeles Times

David Horsey, Los Angeles Times

 Tom Toles, Washington Post, 6/6/2016

Tom Toles, Washington Post, 6/6/2016

 Mike Luckovich, Atlanta Journal-Constitution

Mike Luckovich, Atlanta Journal-Constitution

References:

[1] Hansen, J., M. Sato, P. Hearty, R. Ruedy, M. Kelley, V. Masson-Delmotte, G. Russell, G. Tselioudis, J. Cao, E. Rignot, I. Velicogna, B. Tormey, B. Donovan, E. Kandiano, K. von Schuckmann, P. Kharecha, A.N. LeGrande, M. Bauer, and K. Lo: Ice melt, sea level rise and superstorms: Evidence from paleoclimate data, climate modeling, and modern observations that 2°C global warming could be dangerous. Atmos. Chem. Phys., 16, 3761-3812, 2016.

[2] Hansen, J., M. Sato, P. Kharecha, K. von Schuckmann, D.J. Beerling, J. Cao, S. Marcott, V. Masson-Delmotte, M.J. Prather, E.J. Rohling, J. Shakun, P. Smith, A. Lacis, G. Russell, and R. Ruedy: Young people’s burden: Requirement of negative CO2 emissions. Earth Syst. Dynam., 8, 577-616, doi:10.5194/esd-8-577-2017, 2017.

[3] Intergovernmental Panel on Climate Change Sixth Assessment Report (https://wg1.ipcc.ch/AR6/AR6.html).

[4] Hansen, J., M. Sato, P. Hearty, R. Ruedy, M. Kelley, V. Masson-Delmotte, G. Russell, G. Tselioudis, J. Cao, E. Rignot, I. Velicogna, B. Tormey, B. Donovan, E. Kandiano, K. von Schuckmann, P. Kharecha, A.N. LeGrande, M. Bauer, and K.-W. Lo: Ice melt, sea level rise and superstorms: Evidence from paleoclimate data, climate modeling, and modern observations that 2°C global warming could be dangerous. Atmos. Chem. Phys., 16, 3761-3812, 2016.

[5] Intergovernmental Panel on Climate Change Sixth Assessment Report (https://wg1.ipcc.ch/AR6/AR6.html).

[6] Hansen, J., M. Sato, P. Kharecha, K. von Schuckmann, D.J. Beerling, J. Cao, S. Marcott, V. Masson-Delmotte, M.J. Prather, E.J. Rohling, J. Shakun, P. Smith, A. Lacis, G. Russell, and R. Ruedy: Young people’s burden: Requirement of negative CO2 emissions. Earth Syst. Dynam., 8, 577-616, 2017.

[7] Hansen, J.E.: Scientific reticence and sea level rise. Environ. Res. Lett., 2, 024002, 2007.

[8] Eipper, A.W.: Pollution problems, resource policy, and the scientist, Science, 169, 11-15, 1970.

[9] Hansen, J., D. Johnson, A. Lacis, S. Lebedeff, P. Lee, D. Rind, and G. Russell: Climate impact of increasing atmospheric carbon dioxide. Science, 213, 957-966, doi:10.1126/science.213.4511.957, 1981

[10] Hansen, J., I. Fung, A. Lacis, D. Rind, S. Lebedeff, R. Ruedy, G. Russell, and P. Stone: Global climate changes as forecast by Goddard Institute for Space Studies three-dimensional model. J. Geophys. Res., 93, 9341-9364, 1988.

[11] Sullivan, W.: Study finds warming trend that could raise sea levels, New York Times, 22 August 1981.

[12] Rasool, S.I.: On predicting calamities, Clim. Change, 5, 201-202, 1983.

[13] Hansen, J., et al.: Response to “On predicting calamities”, Clim. Change, 5, 201-202, 1983.

[14] MacCracken, M.C.: Climatic effects of atmospheric carbon dioxide, Science, 220, 873-874, 1983.

[15] Hansen, J., et al.: Response to MacCracken and Idso, Science, 220, 874-875, 1983.

[16] Kerr, R.A.: Hansen vs. the world on the greenhouse threat, Science, 244, 1041-1043, 1989.

[17] Hansen, J., A. Lacis, D. Rind, G. Russell, P. Stone, I. Fung, R. Ruedy, and J. Lerner: Climate sensitivity: Analysis of feedback mechanisms. In Climate Processes and Climate Sensitivity. J.E. Hansen and T. Takahashi, Eds., AGU Geophysical Monograph 29, Maurice Ewing Volume 5. American Geophysical Union, 130-163, 1984.

[18] We compared the last glacial maximum (LGM, the period about 20,000 years ago when a large ice sheet covered Canada and parts of the United States) with the present interglacial period.  We could use data for these two periods to find an accurate empirical measure of the fast-feedback climate sensitivity, which is the climate sensitivity relevant to decade-century time scales, by taking ice sheet size and long-lived GHG amounts as specified boundary conditions in both periods.  However, on longer time scales ice sheet size and CO2 amount are slow amplifying feedbacks, which accounts for the extraordinarily high climate sensitivity on millennial time scales.  The high sensitivity on millennial time scales is the reason that small climate forcings caused by perturbations of Earth’s orbit and the tilt of Earth’s spin axis cause large glacial-to-interglacial climate oscillations.

[19] Lacis, A., J. Hansen, P. Lee, T. Mitchell, and S. Lebedeff: Greenhouse effect of trace gases, 1970-1980. Geophys. Res. Lett., 8, 1035-1038, doi:10.1029/GL008i010p01035, 1981.

[20] A few months after I was appointed as Director of the Goddard Institute for Space Studies in 1981, I received direction from management of the parent Goddard Space Flight Center (GSFC) to make preparations to move the Institute to the main campus in Greenbelt, Maryland.  After getting support of a few key staff members, I told the GSFC Director that they would only get used government furniture – none of us were going.  We were allowed to stay near the Columbia University campus, but the GSFC Director told me that we could never expect much resources if we remained remote.  Fortunately, we were able to use money saved by cancelling the maintenance contract on our IBM 360-95 (1967 vintage) to purchase a used Amdahl (1975 vintage).  The latter was a bit faster than the old IBM, reliable, and low maintenance.  By the middle and late 1980s our computer capacity was a factor of 10 to 100 less than that of the other major modeling groups, but we had the advantage of an academic environment away from the growing NASA bureaucracy.

[21] Scenario A had rapid growth of annual GHG emissions, as occurred in 1950-1980 (see Fig. 8 of Young People’s Burden3).  Scenario C assumed 21st century GHG emissions would decrease to a level just balancing GHG sinks.

[22] The annual growth of GHG forcing increased rapidly from ~0.02 W/m2 per year in 1958 to ~0.045 W/m2 per year in the early 1980s; it then fell to ~0.035 W/m2, remaining at that level until the past five years when it increased sharply to ~0.045 W/m2 per year, belying a misperception that the corner has been turned on the global warming problem (see Figs. 8 and 14 in Young People’s Burden3).

[23] The high model sensitivity was later traced to an excessive amplifying cloud feedback.  Next most important model deficiencies were (a) unchanging tropospheric aerosols, and (b) assumption of energy balance when the simulation was initiated, i.e., in 1958.  These approximations affected global temperature in opposite senses and were thus at least partially offsetting.

[24] IPCC (Intergovernmental Panel on Climate Change): Climate Change 2013, edited by: Stocker, T., Qin, D., Q., Plattner, G. K., Tignor, M. M. B., Allen, S. K., Boschung, J., Nauels, A., Xia, Y., Bex, V., and Midgley, P. M., Cambridge University Press, 1535 pp., 2013.

[25] A1B, a “business-as-usual” scenario in earlier IPCC reports, falls between recent RCP8.5 and RCP6.0 scenarios.

[26] Hansen, J.: Storms of My Grandchildren, New York, Bloomsbury, 304 pp., 2009.

[27] Shaffer, G., Olsen, S.M., and Bjerrum, C.J.: Ocean subsurface warming as a mechanism for coupling Dansgaard-Oeschger climate cycles and ice-rafting events, Geophys. Res. Lett., 31(24), L24202, 2004.

[28] Petersen, S.V., Schrag, D.P., and Clark, P.U.: A new mechanism for Dansgaard-Oeschger cycles, Paleoceanography, 28, 24-30, 2013.

[29] Model insensitivity to freshwater injection could be related to diffusive effects of parameterized small-scale mixing in coarse-resolution ocean models, as discussed in the Ice Melt paper.

[30] Rignot, E., Velicogna, I., van den Broeke, M.R., Monaghan, A., and Lenaerts, J.T.M.: Acceleration of the contribution of the Greenland and Antarctic ice sheets to sea level rise, Geophys. Res. Lett., 38, L05503, 2011.

[31] Mercer, J.H.: West Antarctic ice sheet and CO2 greenhouse effect: a threat of disaster, Nature, 271, 321-325, 1978

[32] Paris Agreement, UNFCCC secretariat, available at http://unfccc.int/paris_agreement/items/9485.php, 2015.

[33] Smith, P., Davis, S., Creutzig, F., Fuss, S., Minx, J., Gavrielle, B., Kato, E., Jackson, R., Cowie, A., Kriegler, E., van Vuuren, D., et al.: Biophysical and economic limits to negative CO2 emissions, Nat. Clim. Chan., 6, 42-50,2016.

[34] Hansen, J.E.: A slippery slope: How much global warming constitutes “dangerous anthropogenic interference”? An editorial essay. Clim. Change 68, 269-279, doi:10.1007/s10584-005-4135-0, 2005.

[35] Hansen, J.: Storms of My Grandchildren, New York, Bloomsbury, 304 pp., 2009.

[36] Hearty, P.J. and Tormey, B.R.: Sea-level change and superstorms; geologic evidence from the last interglacial (MIS 5e) in the Bahamas and Bermuda offers ominous prospects for a warming Earth, Marine Geology, 390, 347-365, 2017.

 

September 2017 Global Temperature Update

September 2017 Global Temperature Update

To sign up for our monthly update of global temperature (Maps and Graphs), click here.

Additional figures are on our global temperature web page.

 

image-sept 2017.png

Globally September 2017 was the fourth warmest September since reliable measurements began in 1880, 0.80C warmer than the 1951-1980 mean.  Warmest Septembers were 2014 and 2016 at +0.87C, with 2015 third at 0.82C.

The 2017 January to September 9-month mean is second highest, behind 2016, compared to the first nine months of other years, as shown above.

If the temperature anomaly for the next three months (relative to the 1951-1980 mean) is less than 0.75C (i.e., if October-December 2017 is more than 0.33C cooler than October-December 2015) the annual 2017 temperature would fall below that of 2015, making 2017 the third warmest year.  Even though a La Nina may be in the offing for this fall-winter, a cooling that large seems unlikely, so 2017 will probably be the second warmest year.

North Dakota Conviction

North Dakota Conviction

11 October 2017

James Hansen

Michael Foster (see How Does It Feel) was convicted on 6 October on three of four counts, two felonies and one misdemeanor. He will be sentenced in January. Judge Fontaine ruled earlier that the “necessity” defense was not allowed. We hoped I would still be able to testify about the threat of climate change and urgency of fossil fuel phaseout, to make the jury aware of factors affecting Foster’s state of mind and his action. However, this too was not allowed.

I prefer taking the offensive, lawsuits against the real criminals, but let’s consider the necessity defense and Foster’s specific situation. The necessity defense requires showing that:

(1) there is no legal alternative to violating the law,

(2) the harm to be prevented is imminent, and

(3) a direct, causal relationship exists between defendant’s action and the avoidance of harm.[1]

Michael Foster. I can’t imagine a more sympathetic figure than Foster. He reached the point of committing a supposed felony, turning off a tar sands pipeline, after decades of growing concern and increasing efforts to take helpful actions. He walked the naturist talk, minimized his and his family’s carbon footprint, became a vegetarian, even raising backyard chickens, showed that it was possible to live an American life while treading lightly on the planet.

As governments failed to take action on climate change, his concerns grew and his efforts to do something became almost superhuman. He started the website ClimateChangeforFamilies.com, founded Plant-for-the-Planet NorthWest, and co-founded 350 Seattle. He became a speaker for the Climate Reality Project, giving a slideshow to more than 13,000 people, but rather than just the standard slideshow, he included a pathway to a solution, as specified in our 2013 Plos One paper (emission reduction of several percent per year and 100 PgC carbon drawdown via improved agricultural and forestry practices). He became a parent coordinator for the Our Children’s Trust (OCT) lawsuit against Washington State, to name just some of his activities.

These were the actions of a feeling adult with a masters of education in counseling psychology. In counseling adolescents and families he observed the increased anxiety and stress that today’s youth face, a fact partially attributable to realization that young people face lesser prospects and difficult times because of climate change. As a practicing professional in the mental health area, he saw continuing governmental failure to address climate change as tantamount to child abuse.

The historic “victory” in the OCT lawsuit against Washington State added to Foster’s frustration. Washington supposedly must reduce emissions on a pathway that, if adopted globally, would return atmospheric CO2 to 350 ppm by 2100. In reality Washington’s minimalist actions have little effect. Foster relates a “celebration” of Governor Inslee on stage with the kids, while his reality is “half-measures” and “soothing and baffling expedients” that promise young people only a “period of consequences,” tantamount, indeed, to child abuse.

  Fig. 1. &nbsp; Global surface temperature relative to 1880-1920 based on GISTEMP analysis.&nbsp; Data extend through August 2017.&nbsp; Update of Fig. 1 of Young people’s burden,  Earth Syst. Dynam . 8, 1-40, 2017.

Fig. 1.  Global surface temperature relative to 1880-1920 based on GISTEMP analysis.  Data extend through August 2017.  Update of Fig. 1 of Young people’s burden, Earth Syst. Dynam. 8, 1-40, 2017.

 

Imminent Danger and Urgency of Action. One cannot recognize the imminent danger without understanding the science. It is not difficult science. The urgency of action arises from the slow response of the climate system to changes of atmospheric composition. This slow response means that there is more global warming “in the pipeline” without further increase of greenhouse gases (GHGs). Delayed warming is due mainly to the large thermal inertia of the ocean.

Delayed response of the ice sheets, and thus sea level rise, is due to both the thermal inertia of the ocean and dynamic inertia of the ice sheets. A warming ocean melts the ice shelves around Antarctica and Greenland, tongues of ice reaching into the ocean that buttress the ice sheet, which allows more rapid discharge of land ice to the ocean, speeding ice sheet disintegration.

The delayed response is dangerous in one sense, because it allows greater climate change and consequences to build up before effects become large enough to awaken the public to danger. On the other hand, the delayed response allows global warming to be kept less than 1.5°C relative to the 1880-1920 mean (Fig. 2a), assuming that emission reductions begin soon.

Earth begins to cool after fossil fuel emissions are eliminated, but the rate of cooling is very slow (Fig. 2a). Therefore, if it is desired to return global temperature close to Holocene levels within a century, it necessary to somehow extract a large amount of CO2 from the air (Fig. 2b). The largest carbon extraction that can be achieved by natural processes such as reforestation and improved agricultural and forestry practices is not more than [2] about 100 PgC.

The target to keep global warming below 1.5°C is included in the 2015 Paris climate agreement as an ambitious goal, but without scientific justification. In fact 1.5°C is 1°C warmer than the maximum temperature in the Holocene, the past 10 thousand years in which civilization developed and most of the world’s large cities were established on coastlines. Indeed, 1.5°C is at least as warm as, but probably warmer than, the Eemian period, about 120,000 years ago [2], when sea level reached 6-9 meters (20-30 feet) higher than today. Earth’s paleoclimate history shows that sea level responds to global temperature change with a lag of 1-4 centuries [3], but the paleoclimate forcings were much weaker and slower than the present human-made increases of atmospheric GHGs. Therefore it would be dangerous to leave global temperature at a level that is expected to eventually yield sea level rise of several meters.

  Fig. 2.  &nbsp;Simulated global temperature for alternative emission growth rates.&nbsp; Observations as in Fig. 1.&nbsp; Gray area is 2σ (95% confidence) range for centennially-smoothed Holocene maximum temperature.&nbsp; Fig. 12 of Young people’s burden,  Earth Syst. Dynam . 8, 1-40, 2017.

Fig. 2.  Simulated global temperature for alternative emission growth rates.  Observations as in Fig. 1.  Gray area is 2σ (95% confidence) range for centennially-smoothed Holocene maximum temperature.  Fig. 12 of Young people’s burden, Earth Syst. Dynam. 8, 1-40, 2017.

If emissions reduction of 6%/year had begun in 2013, and if 100 PgC (1 PgC = 1 GtC = one billion tons of carbon) were removed from the air via reforestation and carbon storage in the soil and biosphere via improved agricultural and forestry practices, atmospheric CO2 would have declined to 350 ppm by 2100 and temperature returned close to the Holocene range. [4] The simulations for Fig. 2 have reductions beginning in 2021 relative to 2020, based on the fact that it will take at least a few years to achieve global policies, such as a carbon fee or tax that would be essential to achieve rapid sustained emission reductions. The delay from 2013 to 2021 increases the requirement for carbon extraction from the air by 53 PgC, if emission reductions of 6%/year are possible, or 137 PgC, if reductions are at the easier rate of 3%/year.

The requirement of extracting CO2 from the atmosphere will fall upon today’s young people and their children, as today’s adults have yet to develop and seriously consider, no less commit to, any serious program to extract of massive amounts of CO2 from the air. This “young people’s burden,” the need to somehow achieve negative CO2 emissions in the middle and latter part of this century, has been quietly inserted into all studies of the United Nations modeling group (IPCC) in their scenarios that attempt to stabilize climate. But it simply will not happen absent a conscious, concerted international effort, and its costs seem likely to be unbearable.

Let us first note the estimated cost of negative emissions. Smith et al. (2016) [5] review estimated costs for a wide range of proposed methods of extracting CO2, concluding that costs are at least $150-350/tC, where tC is a ton of carbon. Thus the cost of extracting 100 PgC is $15-35 trillion. Let’s assume the emitting nations agree to cover this cost, spread over the last 75 years of this century. The bill would be $200-467 billion/year. The United States is responsible for 25% of the excess CO2 in the air from fossil fuel use, so the proportionate U.S. annual bill is $50-117 billion/year for each 100 PgC of extraction.

However, carbon extraction needed to stabilize climate is likely to be much more than 100 PgC. If fossil fuel emissions remain constant, the extraction requirement is 695 PgC (Fig. 2). Thus the cost of removing the CO2 from the air would be about a factor of seven larger than for 100 PgC. I am not saying that young people will actually be able to come up with the resources to clean up this mess. Our “Young People’s Burden” paper [2] concluded that “Continued high fossil fuel emissions unarguably sentences young people to either a massive, implausible cleanup or growing deleterious climate impacts or both.”

The tragedy of this situation is that there is little if any net cost of rapidly reducing fossil fuel emissions – and thus to reduce the burden for young people to a still-huge but potentially still-manageable level — if emissions reductions are secured via a gradually increasing across-the-board (oil, gas, coal) carbon fee collected from fossil fuel companies at domestic mines and ports of entry with the funds distributed uniformly to the public (see references in the Burden paper).

Foster’s Defense. Michael Foster is a mental health professional deeply concerned about the well-being of young people and the global mess that we are leaving them. Michael Foster is not a scientist, but when I met him in North Dakota I was shocked at his quantitative knowledge of information in our papers such as Young People’s Burden, and he quoted several lines from my TED talk, including: “What would you do if you knew what I know?” We know what Foster did: he turned off a damned tar sands pipeline. It is a travesty that Foster should go to prison, while those guilty of child neglect and abuse sit lavishly in Washington and corporate headquarters.

As for the necessity defense, the evidence is overwhelming, it seems to me, that the second and third requirements are satisfied, i.e., the harm to be prevented is imminent and there is a causal relation of the defendant’s actions with avoidance of harm. The first requirement, proving that there is no legal alternative to violating the law, is harder to meet. That is the reason I prefer to go on the offense, use the legal system to go after the real criminals.

Michael Foster could have made an argument that the exceedingly slow pace of alternative approaches is inconsistent with the urgency of addressing the present climate emergency. Understanding the urgency of CO2 emission phasedown requires understanding the slow response of the climate system, the role of amplifying feedbacks, and the danger of passing a point of no return. Regrettably, these points are not yet matters of widespread knowledge – and I was not allowed to inform the jury about them.

Accordingly, I think the judge made an egregious error in prohibiting expert testimony relevant to Foster’s state of mind – in particular, the basis for Michael’s understanding of the urgency of emission phasedown and government’s failure to take meaningful action – as I discussed in “How Does It Feel?” The jury should have heard about factors that affected Foster’s state of mind before it determined his guilt as to charges carrying the potential for long prison time .

 

References:

1. United States v. DeChristopher, 695 F.3d 1082, 1096 (10th Circuit 2012).

2. Hansen, J., M. Sato, P. Kharecha, K. von Schuckmann, D.J. Beerling, J. Cao, S. Marcott, V. Masson-Delmotte, M.J. Prather, E.J. Rohling, J. Shakun, P. Smith, A. Lacis, G. Russell, and R. Ruedy, 2017: Young people’s burden: Requirement of negative CO2 emissions. Earth Syst. Dynam., 8, 577-616, doi:10.5194/esd-8-577-2017.

3. Grant, K. M., Rohling, E. J., Bar-Matthews, M., Ayalon, A., Medina-Elizalde, M., Ramsey, C. B., Satow, C., and Roberts, A. P.: Rapid coupling between ice volume and polar temperature over the past 150,000 years, Nature, 491, 744-747, 2012.

4. Hansen, J., P. Kharecha, M. Sato, V. Masson-Delmotte, F. Ackerman, D. Beerling, P.J. Hearty, O. Hoegh-Guldberg, S.-L. Hsu, C. Parmesan, J. Rockstrom, E.J. Rohling, J. Sachs, P. Smith, K. Steffen, L. Van Susteren, K. von Schuckmann, and J.C. Zachos: Assessing “dangerous climate change”: Required reduction of carbon emissions to protect young people, future generations and nature. PLOS ONE, 8, e81648, doi:10.1371/journal.pone, 2013.

5. Smith, P., Davis, S. J., Creutzig, F., Fuss, S., Minx, J., Gavrielle, B., Kato, E., Jackson, R. B., Cowie, A., Kriegler, E., van Vuuren, D. P., Rogelj, J., Ciais, P., Milne, J., Canadell, J. G., McCollum, D., Peters, G., Andrew, R., Krey, V., et al.: Biophysical and economic limits to negative CO2 emissions, Nature Clim. Change, 6, 42-50, 2016.