Category Archives: Intergovernmental Panel on Climate Change

Evidence for human-made global warming hits ‘gold standard’

Repost from Reuters

Evidence for human-made global warming hits ‘gold standard’: scientists

Alister Doyle, Environment Correspondent, Feb 25, 2019 / 8:04 AM

OSLO (Reuters) – Evidence for human-made global warming has reached a “gold standard” level of certainty, adding pressure for cuts in greenhouse gases to limit rising temperatures, scientists said on Monday.

“Humanity cannot afford to ignore such clear signals,” the U.S.-led team wrote in the journal Nature Climate Change of satellite measurements of rising temperatures over the past 40 years.

They said confidence that human activities were raising the heat at the Earth’s surface had reached a “five-sigma” level, a statistical gauge meaning there is only a one-in-a-million chance that the signal would appear if there was no warming.

Such a “gold standard” was applied in 2012, for instance, to confirm the discovery of the Higgs boson subatomic particle, a basic building block of the universe.

Benjamin Santer, lead author of Monday’s study at the Lawrence Livermore National Laboratory in California, said he hoped the findings would win over skeptics and spur action.

“The narrative out there that scientists don’t know the cause of climate change is wrong,” he told Reuters. “We do.”

Mainstream scientists say the burning of fossil fuels is causing more floods, droughts, heat waves and rising sea levels.

U.S. President Donald Trump has often cast doubt on global warming and plans to pull out of the 197-nation Paris climate agreement which seeks to end the fossil fuel era this century by shifting to cleaner energies such as wind and solar power.

Sixty-two percent of Americans polled in 2018 believed that climate change has a human cause, up from 47 percent in 2013, according to the Yale Program on Climate Change Communication.

SATELLITE DATA

Monday’s findings, by researchers in the United States, Canada and Scotland, said evidence for global warming reached the five sigma level by 2005 in two of three sets of satellite data widely used by researchers, and in 2016 in the third.

Professor John Christy, of the University of Alabama in Huntsville which runs the third set of data, said there were still many gaps in understanding climate change. His data show a slower pace of warming than the other two sets.

“You may see a certain fingerprint that indicates human influence, but that the actual intensity of the influence is minor (as our satellite data indicate),” he told Reuters.

Separately in 2013, the United Nations’ Intergovernmental Panel on Climate Change (IPCC) concluded that it is “extremely likely”, or at least 95 percent probable, that human activities have been the main cause of climate change since the 1950s.

Peter Stott of the British Met Office, who was among the scientists drawing that conclusion and was not involved in Monday’s study, said he would favor raising the probability one notch to “virtually certain”, or 99-100 percent.

“The alternative explanation of natural factors dominating has got even less likely,” he told Reuters.

The last four years have been the hottest since records began in the 19th century.

The IPCC will next publish a formal assessment of the probabilities in 2021.

“I would be reluctant to raise to 99-100 percent, but there is no doubt there is more evidence of change in the global signals over a wider suite of ocean indices and atmospheric indices,” said Professor Nathan Bindoff, a climate scientist at the University of Tasmania.

Reporting by Alister Doyle, editing by Ed Osmond and Angus MacSwan

SF Chron Perspective: Facing the coming flood with a sense of optimism

Repost from the San Francisco Chronicle

Facing the coming flood with sense of optimism

By Caille Millner, Oct. 19, 2018 2:12 p.m.
The 2017 Russian River flood in Guerneville. A new U.N. climate report says we have about 12 years to do something huge on climate change. Photo: Santiago Mejia / The Chronicle 2017

After I read the United Nations’ new apocalyptic climate change report, I looked to see when my house was going to be underwater.

For this grim task, I set out to model different possibilities with an online sea level rise tool from Cal-Adapt, a public database for research from California scientists and researchers. (Isn’t the internet amazing? It provides those of us who believe in climate change with all the tools we need to find out when it’s going to swallow us whole, and those of us who aren’t willing to be convinced with all the conspiracy theories we need for political arguments.)

I zoomed in to my street and tried the tool’s first option, “no rise.”

My neighborhood remained gray and dry, untouched by the neon blues of inundation.

Comforted, I tried half a meter. That’s about 1.6 feet, which sounded like a lot until I remembered that the California Coastal Commission has told cities to be prepared for more than 10 feet of ocean rise by 2100.

My house wasn’t underwater yet, but suddenly I could no longer get downtown. Nearly 10 feet of water had inundated the area just north of Mission Bay. San Francisco had lost an Interstate 280 exit, and it’s pretty much assured that all of my Muni buses were getting re-routed as well.

I switched to 1 meter (about 3.3 feet).

My house was still OK, but the water was approaching fast.

Many buildings in the surrounding neighborhoods, including Mission Bay and the Dogpatch, were underwater at least some of the time. The Bayview and Hunters Point neighborhoods were receding into marshland. San Francisco’s Board of Supervisors just approved the construction of a new community in India Basin this week that’s going to be soggy as soon as it’s built.

At 1.41 meters (4.6 feet), Hunters Point was half as large as it should have been, South Beach was surrounded by water on all sides, and Interstate 280 was swamped heading out of Potrero Hill.

Ten feet of ocean rise by 2100. I imagined myself standing on my roof and waving a white T-shirt for rescue. In fact, I should start practicing right now — according to that new U.N. climate report, the party starts in just 12 years. Given the level of anxiety I feel about all of this, it’s going to take me at least six years just to loosen up my spine.

Bad joke, I know. And the truth of the matter is that cynical humor — which is quite frankly the most natural human reaction to the news that the world is about to be flooded and there’s nothing you personally can do to stop it — is not going to get us out of this mess.

So what kind of attitude will get us out of this?

I’ve been thinking about that a lot, partially because I’m so terrified by all of the political inaction and partially because I’ve noticed so many otherwise indomitable people responding to the news on climate change with a sense of helplessness.

Like cynical humor, helplessness is a natural reaction. But it won’t work, and neither will telling other people to give up the benefits of modernity to save the Earth. (Everyone I meet in Berkeley is eager to tell me how climate change will evaporate if we all just stop flying on planes, eating meat and having children, but I have yet to see any of them take their own advice.)

What might work?

Optimism.

It’s hard to find optimism anywhere in America in October 2018, but I’m finding it in the lawsuit brought by 21 young people against the U.S. government for failing to tackle climate change.

Levi Draheim, 10 (center), and other youth activists suing the Trump administration over climate change in San Francisco on Dec. 11. Photo: Gabrielle Lurie / The Chronicle 2017

It’s scheduled to go to trial on Oct. 29, and while the Justice Department has asked the Supreme Court to block it from happening, something about their action feels … antediluvian. A lot of that has to do with the fact that the children are unshaken by the size of the fight they’ve taken on.

“I believe that the momentum is on our side,” said one of the plaintiffs, then-17-year-old Nathan Baring, when the kids were presenting their lawsuit before the Ninth Circuit Court of Appeals in San Francisco in December.

The youngest plaintiff, 11-year-old Levi Draheim of Florida, has said that if he doesn’t do this, he may not have a home when he’s older.

It’s the simplest reason to take on this fight, and it’s also the most inspiring one. It smacks of can-do spirit, a trait that used to be associated with American values. I think it’s time we brought it back again.

Why not make fighting climate change our next national challenge, like putting a man on the moon once was? Why not at least believe we can do that, and behave accordingly?

I can tell you this much: Optimistic action sounds like a lot more fun than clicking for your personal flood zone.

Caille Millner is an editorial writer and Datebook columnist for the San Francisco Chronicle. She has worked at the paper since 2006. On the editorial board, she covers a wide range of topics including business, finance, technology, education and local politics. For Datebook, she writes a weekly column on culture.She is the recipient of the Scripps-Howard Foundation’s Walker Stone Award in Editorial Writing and the Society of Professional Journalists’ Editorial Writing Award.

NY Times summary: Landmark U.N. Climate Report: by 2040, inundated coastlines, intensified droughts & poverty

Repost from The New York Times

Major Climate Report Describes a Strong Risk of Crisis as Early as 2040

By Coral Davenport, Oct. 7, 2018
Harry Taylor, 6, played with the bones of dead livestock in Australia, which has faced severe drought. Credit Brook Mitchell/Getty Images

INCHEON, South Korea — A landmark report from the United Nations’ scientific panel on climate change paints a far more dire picture of the immediate consequences of climate change than previously thought and says that avoiding the damage requires transforming the world economy at a speed and scale that has “no documented historic precedent.”

The report, issued on Monday by the Intergovernmental Panel on Climate Change, a group of scientists convened by the United Nations to guide world leaders, describes a world of worsening food shortages and wildfires, and a mass die-off of coral reefs as soon as 2040 — a period well within the lifetime of much of the global population.

The report “is quite a shock, and quite concerning,” said Bill Hare, an author of previous I.P.C.C. reports and a physicist with Climate Analytics, a nonprofit organization. “We were not aware of this just a few years ago.” The report was the first to be commissioned by world leaders under the Paris agreement, the 2015 pact by nations to fight global warming.

The authors found that if greenhouse gas emissions continue at the current rate, the atmosphere will warm up by as much as 2.7 degrees Fahrenheit (1.5 degrees Celsius) above preindustrial levels by 2040, inundating coastlines and intensifying droughts and poverty. Previous work had focused on estimating the damage if average temperatures were to rise by a larger number, 3.6 degrees Fahrenheit (2 degrees Celsius), because that was the threshold scientists previously considered for the most severe effects of climate change.

The new report, however, shows that many of those effects will come much sooner, at the 2.7-degree mark.

The new report, however, shows that many of those effects will come much sooner, at the 2.7-degree mark.

Why Half a Degree of Global Warming Is a Big Deal

It may sound small, but a half-degree of temperature change could lead to more dire consequences in a warming world, according to a sweeping new scientific assessment.

Avoiding the most serious damage requires transforming the world economy within just a few years, said the authors, who estimate that the damage would come at a cost of $54 trillion. But while they conclude that it is technically possible to achieve the rapid changes required to avoid 2.7 degrees of warming, they concede that it may be politically unlikely.

[How much hotter is your hometown today than when you were born? Find out here.]

For instance, the report says that heavy taxes or prices on carbon dioxide emissions — perhaps as high as $27,000 per ton by 2100 — would be required. But such a move would be almost politically impossible in the United States, the world’s largest economy and second-largest greenhouse gas emitter behind China. Lawmakers around the world, including in China, the European Union and California, have enacted carbon pricing programs.

People on a smog-clouded street in Hebei Province, China, in 2016. China is the largest emitter of greenhouse gases, followed by the United States. Credit Damir Sagolj/Reuters

President Trump, who has mocked the science of human-caused climate change, has vowed to increase the burning of coal and said he intends to withdraw from the Paris agreement. And on Sunday in Brazil, the world’s seventh-largest emitter of greenhouse gas, voters appeared on track to elect a new president, Jair Bolsonaro, who has said he also plans to withdraw from the accord.

The report was written and edited by 91 scientists from 40 countries who analyzed more than 6,000 scientific studies. The Paris agreement set out to prevent warming of more than 3.6 degrees above preindustrial levels — long considered a threshold for the most severe social and economic damage from climate change. But the heads of small island nations, fearful of rising sea levels, had also asked scientists to examine the effects of 2.7 degrees of warming.

[What on Earth is going on? Sign up to get our latest stories about climate change.]

Absent aggressive action, many effects once expected only several decades in the future will arrive by 2040, and at the lower temperature, the report shows. “It’s telling us we need to reverse emissions trends and turn the world economy on a dime,” said Myles Allen, an Oxford University climate scientist and an author of the report.

To prevent 2.7 degrees of warming, the report said, greenhouse pollution must be reduced by 45 percent from 2010 levels by 2030, and 100 percent by 2050. It also found that, by 2050, use of coal as an electricity source would have to drop from nearly 40 percent today to between 1 and 7 percent. Renewable energy such as wind and solar, which make up about 20 percent of the electricity mix today, would have to increase to as much as 67 percent.

“This report makes it clear: There is no way to mitigate climate change without getting rid of coal,” said Drew Shindell, a climate scientist at Duke University and an author of the report.

The World Coal Association disputed the conclusion that stopping global warming calls for an end of coal use. In a statement, Katie Warrick, its interim chief executive, noted that forecasts from the International Energy Agency, a global analysis organization, “continue to see a role for coal for the foreseeable future.”

Ms. Warrick said her organization intends to campaign for governments to invest in carbon capture technology. Such technology, which is currently too expensive for commercial use, could allow coal to continue to be widely used.

Despite the controversial policy implications, the United States delegation joined more than 180 countries on Saturday in accepting the report’s summary for policymakers, while walking a delicate diplomatic line. A State Department statement said that “acceptance of this report by the panel does not imply endorsement by the United States of the specific findings or underlying contents of the report.”

The State Department delegation faced a conundrum. Refusing to approve the document would place the United States at odds with many nations and show it rejecting established academic science on the world stage. However, the delegation also represents a president who has rejected climate science and climate policy.

“We reiterate that the United States intends to withdraw from the Paris agreement at the earliest opportunity absent the identification of terms that are better for the American people,” the statement said.

The report attempts to put a price tag on the effects of climate change. The estimated $54 trillion in damage from 2.7 degrees of warming would grow to $69 trillion if the world continues to warm by 3.6 degrees and beyond, the report found, although it does not specify the length of time represented by those costs.

The report concludes that the world is already more than halfway to the 2.7-degree mark. Human activities have caused warming of about 1.8 degrees since about the 1850s, the beginning of large-scale industrial coal burning, the report found.

Climate Change Is Complex. We’ve Got
Answers to Your Questions.

We know. Global warming is daunting. So here’s a place to start: 17 often-asked questions with some straightforward answers.

The United States is not alone in failing to reduce emissions enough to prevent the worst effects of climate change. The report concluded that the greenhouse gas reduction pledges put forth under the Paris agreement will not be enough to avoid 3.6 degrees of warming.

The report emphasizes the potential role of a tax on carbon dioxide emissions. “A price on carbon is central to prompt mitigation,” the report concludes. It estimates that to be effective, such a price would have to range from $135 to $5,500 per ton of carbon dioxide pollution in 2030, and from $690 to $27,000 per ton by 2100.

By comparison, under the Obama administration, government economists estimated that an appropriate price on carbon would be in the range of $50 per ton. Under the Trump administration, that figure was lowered to about $7 per ton.

The World Coal Association disputed the conclusion that stopping global warming calls for an end of coal use. Credit Kevin Frayer/Getty Images

Americans for Prosperity, the political advocacy group funded by the libertarian billionaires Charles and David Koch, has made a point of campaigning against politicians who support a carbon tax.

“Carbon taxes are political poison because they increase gas prices and electric rates,” said Myron Ebell, who heads the energy program at the Competitive Enterprise Institute, an industry-funded Washington research organization, and who led the Trump administration’s transition at the Environmental Protection Agency.

The report details the economic damage expected should governments fail to enact policies to reduce emissions. The United States, it said, could lose roughly 1.2 percent of gross domestic product for every 1.8 degrees of warming.

A wildfire in Shasta-Trinity National Forest in California last month. The new I.P.C.C. research found that wildfires are likely to worsen if steps are not taken to tame climate change. Credit Noah Berger/Associated Press

In addition, it said, the United States along with Bangladesh, China, Egypt, India, Indonesia, Japan, the Philippines and Vietnam are home to 50 million people who will be exposed to the effects of increased coastal flooding by 2040, if 2.7 degrees of warming occur.

At 3.6 degrees of warming, the report predicts a “disproportionately rapid evacuation” of people from the tropics. “In some parts of the world, national borders will become irrelevant,” said Aromar Revi, director of the Indian Institute for Human Settlements and an author of the report. “You can set up a wall to try to contain 10,000 and 20,000 and one million people, but not 10 million.”

The report also finds that, in the likelihood that governments fail to avert 2.7 degrees of warming, another scenario is possible: The world could overshoot that target, heat up by more than 3.6 degrees, and then through a combination of lowering emissions and deploying carbon capture technology, bring the temperature back down below the 2.7-degree threshold.

In that scenario, some damage would be irreversible, the report found. All coral reefs would die. However, the sea ice that would disappear in the hotter scenario would return once temperatures had cooled off.

“For governments, the idea of overshooting the target but then coming back to it is attractive because then they don’t have to make such rapid changes,” Dr. Shindell said. “But it has a lot of disadvantages.”

For more news on climate and the environment, follow @NYTClimate on Twitter.  Coral Davenport covers energy and environmental policy, with a focus on climate change, from the Washington bureau. She joined The Times in 2013 and previously worked at Congressional Quarterly, Politico and National Journal.