Antarctica: ...and still it melts

President Trump announced his decision June 1 to pull the United States out of the Paris Agreement on Climate, signed by 195 nations and formally joined by 147, including the US. The United States now joins Syria and Nicaragua as the only nations in the world not supporting the accord. Nicaragua, it should be noted, failed to join because the terms of the accord are not binding, and it was therefore considered too weak. Syria is consumed by internal war, and was iced from the negotiations by restrictions on its envoys traveling to the talks. The agreement, which seeks to limit global warming to 2°C above pre-industrial levels, came into force on Nov. 4, 2016, just days before Trump was elected. Each country sets its own commitments under the accord. The United States, second-largest emitter on the planet after China, had committed to reducing its carbon emissions by 26 to 28% below 2005 levels by 2025. It also commited up to $3 billion in aid for poorer countries to address climate change by 2020. (ENS, June 2; NYT, June 1; WP, May 31)

Ominously, Trump's announcement comes just as scienists report that s massive crack in an Antarctic ice shelf has grown by 11 miles in the past six days—with one of the world's biggest icebergs ever poised to break off. The crack in the Larsen C ice shelf is now about 120 miles long, and only eight miles remain until it cuts all the way across, producing an iceberg about the size of the state of Delaware.

Adrian Luckman of Project MIDAS, a British research project that is monitoring crack, said this week saw the largest jump since January. The breaking point, known as "calving," is now said to be "very close."  Once the iceberg breaks off, it "will fundamentally change the landscape of the Antarctic Peninsula." (USA Today, CNN, Gizmodo, June 1)

This development comes as a "shockingly green" landscape across parts of Antarctica as warming temperatures allow moss to flourish. (The Weather Channel, May 30)

Three years to prevent climate catastrophe

From The Independent, June 29:

The world has three years to start making significant reductions in greenhouse gas emissions or face the prospect of dangerous global warming, experts have warned in an article in the prestigious journal Nature.

Calling for world leaders to be guided by the scientific evidence rather than "hide their heads in the sand," they said "entire ecosystems" were already beginning to collapse, summer sea ice was disappearing in the Arctic and coral reefs were dying from the heat.

The world could emit enough carbon to bust the Paris Agreement target of between 1.5 to 2 degrees Celsius in anything from four to 26 years if current levels continue, the article said.

Global emissions had been rising rapidly but have plateaued in recent years. The experts, led by Christiana Figueres, who as Executive Secretary of the United Nations Framework Convention on Climate Change played a key role in the Paris Agreement, said they must start to fall rapidly from 2020 at the latest.

Note that James Hansen and others have already predicted that even with the 2 degrees Celsius lmit established by the Paris Accord that the US just abandoned, New York, London, Calcutta, Shanghai and many other cities will be flooded and basically uninhabitable within a century. If current carbon output levels continue, we'll reach 6 degrees within a century, which would likely mean human extinction. A rise of 11 degrees has been broached. (AFP, Nov. 30, 2015; Slate, July 20, 2015; CNN, May 22, 2015; WP. Nov. 28, 2011)

Disintegration of Antarctic ice shelf: it's on

Well, that crack in the Larsen C ice shelf has now cut all the way across, producing (as predicted) an iceberg about the size of the state of Delaware. The ice shelf is now 12% smaller. The new massive 'berg weighs a trillion tons and contains as much water as Lake Erie—the biggest iceberg ever recorded. The media are full of don't-worry-be-happy commentators who keep reminding us that the giant breakaway iceberg will have no impact on sea level because the ice shelf itself was already resting on the ocean. More sober voices point out that as the ice shelves deteriorate, the inland ice sheets will start sliding into the sea. If the entire West Antarctic Ice Sheet were to melt, it would raise sea levels by a devastating 15 feet. Of course this would "take centuries," so don't worry about it. Fuck posterity, right?

In 2002, an ice shelf the size of Rhode Island, the Larsen B, broke apart in two weeks...(Mashable, The Verge, NPR, Gizmodo)

Era of 'Biological Annihilation' underway

From the New York Times, July 11:

From the common barn swallow to the exotic giraffe, thousands of animal species are in precipitous decline, a sign that an irreversible era of mass extinction is underway, new research finds.

The study, published Monday in the Proceedings of the National Academy of Sciences, calls the current decline in animal populations a "global epidemic" and part of the "ongoing sixth mass extinction" caused in large measure by human destruction of animal habitats. The previous five extinctions were caused by natural phenomena.

Gerardo Ceballos, a researcher at the Universidad Nacional Autónoma de México in Mexico City, acknowledged that the study is written in unusually alarming tones for an academic research paper. "It wouldn't be ethical right now not to speak in this strong language to call attention to the severity of the problem," he said.

Dr. Ceballos emphasized that he and his co-authors, Paul R. Ehrlich and Rodolfo Dirzo, both professors at Stanford University, are not alarmists, but are using scientific data to back up their assertions that significant population decline and possible mass extinction of species all over the world may be imminent, and that both have been underestimated by many other scientists.

So here we are reading in the MSM that the sixth mass extinction is imminent or underway—the first (obviously) that is anthropogenic. This raises the question of whether we humans really are rational, conscious beings or, ultimately, a blind force of nature, like the meteor that wiped out the dinosaurs at the end of the Cretaceous...

The industrial system that is driving this planetary collapse is the fruit of rationalism. Yet its continuance is so thoroughly irrational. It's such a paradox.

Meanwhile, the oceans are dying...

As we've (repeatedly) noted. But PhysOrg Sept. 20 reports the findings of MIT geophysics professor Daniel Rothman that if 310 gigatons of carbon are added to the oceans, it will trigger Planet Earth's "sixth mass extinction." This is on track to happen by 2100.

"This is not saying that disaster occurs the next day," Rothman says. "It's saying that, if left unchecked, the carbon cycle would move into a realm which would be no longer stable, and would behave in a way that would be difficult to predict. In the geologic past, this type of behavior is associated with mass extinction."

In the past 540 million years, the Earth has endured five mass extinction events, each involving processes that upended the normal cycling of carbon through the atmosphere and oceans. These globally fatal perturbations in carbon each unfolded over thousands to millions of years, and are coincident with the widespread extermination of marine species around the world.

The question for many scientists is whether the carbon cycle is now experiencing a significant jolt that could tip the planet toward a sixth mass . In the modern era, carbon dioxide emissions have risen steadily since the 19th century, but deciphering whether this recent spike in carbon could lead to mass extinction has been challenging. That's mainly because it's difficult to relate ancient carbon anomalies, occurring over thousands to millions of years, to today's disruptions, which have taken place over just a little more than a century.

Now Daniel Rothman, professor of geophysics in the MIT Department of Earth, Atmospheric and Planetary Sciences and co-director of MIT's Lorenz Center, has analyzed significant changes in the carbon cycle over the last 540 million years, including the five . He has identified "thresholds of catastrophe" in the carbon cycle that, if exceeded, would lead to an unstable environment, and ultimately, mass extinction.

In a paper published in Science Advances, he proposes that mass extinction occurs if one of two thresholds are crossed: For changes in the carbon cycle that occur over long timescales, extinctions will follow if those changes occur at rates faster than global ecosystems can adapt. For carbon perturbations that take place over shorter timescales, the pace of carbon-cycle changes will not matter; instead, the size or magnitude of the change will determine the likelihood of an extinction event.

Taking this reasoning forward in time, Rothman predicts that, given the recent rise in carbon dioxide emissions over a relatively short timescale, a sixth extinction will depend on whether a critical amount of carbon is added to the oceans. That amount, he calculates, is about 310 gigatons, which he estimates to be roughly equivalent to the amount of carbon that human activities will have added to the world's oceans by the year 2100.

Does this mean that mass extinction will soon follow at the turn of the century? Rothman says it would take some time—about 10,000 years—for such ecological disasters to play out. However, he says that by 2100 the world may have tipped into "unknown territory."

"This is not saying that disaster occurs the next day," Rothman says. "It's saying that, if left unchecked, the carbon cycle would move into a realm which would be no longer stable, and would behave in a way that would be difficult to predict. In the geologic past, this type of behavior is associated with mass extinction."

Read more at: https://phys.org/news/2017-09-mathematics-sixth-mass-extinction.html#jCp

In the past 540 million years, the Earth has endured five mass extinction events, each involving processes that upended the normal cycling of carbon through the atmosphere and oceans. These globally fatal perturbations in carbon each unfolded over thousands to millions of years, and are coincident with the widespread extermination of marine species around the world.

The question for many scientists is whether the carbon cycle is now experiencing a significant jolt that could tip the planet toward a sixth mass . In the modern era, carbon dioxide emissions have risen steadily since the 19th century, but deciphering whether this recent spike in carbon could lead to mass extinction has been challenging. That's mainly because it's difficult to relate ancient carbon anomalies, occurring over thousands to millions of years, to today's disruptions, which have taken place over just a little more than a century.

Now Daniel Rothman, professor of geophysics in the MIT Department of Earth, Atmospheric and Planetary Sciences and co-director of MIT's Lorenz Center, has analyzed significant changes in the carbon cycle over the last 540 million years, including the five . He has identified "thresholds of catastrophe" in the carbon cycle that, if exceeded, would lead to an unstable environment, and ultimately, mass extinction.

In a paper published in Science Advances, he proposes that mass extinction occurs if one of two thresholds are crossed: For changes in the carbon cycle that occur over long timescales, extinctions will follow if those changes occur at rates faster than global ecosystems can adapt. For carbon perturbations that take place over shorter timescales, the pace of carbon-cycle changes will not matter; instead, the size or magnitude of the change will determine the likelihood of an extinction event.

Taking this reasoning forward in time, Rothman predicts that, given the recent rise in carbon dioxide emissions over a relatively short timescale, a sixth extinction will depend on whether a critical amount of carbon is added to the oceans. That amount, he calculates, is about 310 gigatons, which he estimates to be roughly equivalent to the amount of carbon that human activities will have added to the world's oceans by the year 2100.

Does this mean that mass extinction will soon follow at the turn of the century? Rothman says it would take some time—about 10,000 years—for such ecological disasters to play out. However, he says that by 2100 the world may have tipped into "unknown territory."

"This is not saying that disaster occurs the next day," Rothman says. "It's saying that, if left unchecked, the carbon cycle would move into a realm which would be no longer stable, and would behave in a way that would be difficult to predict. In the geologic past, this type of behavior is associated with mass extinction."

Read more at: https://phys.org/news/2017-09-mathematics-sixth-mass-extinction.html#jCp

EPA to repeal Obama-era Clean Power Plan

The Environmental Protection Agency (EPA) announced Oct. 9 its intention to repeal the Clean Power Plan (summary), an Obama-era policy that worked to curb greenhouse gas emissions from power plants. EPA administrator Scott Pruitt will produce a formal order which is expected to declare that plan exceeded federal law by setting emissions standards that power plants could not reasonably meet. (Jurist)

Pruitt, as attorney general of Oklahoma, had launched suit to overturn the Clean Power Plan. This was but one of Pruiit's challenges as AG against the EPA, the agency he was appointed by Trump to lead. In nearly all of them, regulated industry players also were parties. (NYT, Jan. 14)

The executive order launching the Clean Power Plan was overturned by Trump in March.

EPA to revise Obama emissions standards

EPA head Scott Pruitt on April 2 announced the agency's intent to revise greenhouse gas emissions standards for cars and light trucks. The emissions standards will affect vehicles with model years of 2022-2025. Pruitt criticized the Obama administration's emissions standards, saying the former administration "made assumptions about the standards that didn't comport with reality, and set the standards too high." (Jurist)

Cost of new EPA coal rules: 1,400 more deaths a year

The Environmental Protection Agency (EPA) on Tuesday announced a regulation change (PDF) to replace the Obama administration’s Clean Power Plan with the Affordable Clean Energy (ACE) rule. In the EPA's press release, acting administrator Andrew Wheeler said: "The ACE Rule would restore the rule of law and empower states to reduce greenhouse gas emissions and provide modern, reliable, and affordable energy for all Americans." (Jurist)

The EPA's own analysis reveals that the new rules could also lead to as many as 1,400 premature deaths annually by 2030 from an increase in particulate matter linked to heart and lung disease, up to 15,000 new cases of upper respiratory problems, a rise in bronchitis, and tens of thousands of missed school days. (NYT)

EPA announces plan to ease restrictions on power plants

The Environmental Protection Agency (EPA) proposed major revisions to the Mercury and Air Toxics Standards on Dec. 28, which will ease restrictions and create financial benefits to coal and oil-fired power plants. (Jurist)

National Climate Assessment faces grim reality

The new National Climate Assessment finds climate change is affecting the United States more than ever, the impacts are expected to increase, and that there is "no convincing alternative explanation" for it. Aspects of the system seems to be functioning autonomously, apart from the mandates of the executive. (NYT, WP, Nov. 3)

Meanwhile, the oceans are dying...

Ocean dead zones with zero oxygen have quadrupled in size since 1950, scientists have warned, while the number of very low oxygen sites near coasts have multiplied tenfold. Most sea creatures cannot survive in these zones and current trends would lead to mass extinction in the long run, risking dire consequences for the hundreds of millions of people who depend on the sea.

Climate change caused by fossil fuel burning is the cause of the large-scale deoxygenation, as warmer waters hold less oxygen. The coastal dead zones result from fertilizer and sewage running off the land and into the seas.

The analysis, published in the journal Science, is the first comprehensive analysis of the areas and states: "Major extinction events in Earth's history have been associated with warm climates and oxygen-deficient oceans." 

Said Denise Breitburg at the Smithsonian Environmental Research Center: "Under the current trajectory that is where we would be headed. But the consequences to humans of staying on that trajectory are so dire that it is hard to imagine we would go quite that far down that path." (The Guardian, Jan. 4)

And on what does Dr. Breitburg base this optimism?

Global carbon emissions hit record high in 2017

Global energy-related carbon emissions rose to a historic high of 32.5 gigatons last year, after three years of being flat, due to higher energy demand and the slowing of efficiency improvements, the International Energy Agency said. Most major economies saw an increase in carbon emissions, though Britain, the United States, Mexico and Japan experienced declines. The biggest drop came from the United States, where they were down 0.5 percent to 4.8 gigatons due to higher renewables deployment. (Reuters)

Global insect collapse portends 'Armageddon'

The number of flying insects has plummeted by 75% in the last 25 years, according to a study—with prfound implications for humanity, as insects provide an essential role for life on earth as pollinators of plants and prey for larger animals. Dave Goulson, professor of life sciences at the University of Sussex and the study’s co-author, said: "Insects make up about two-thirds of all life on Earth but there has been some kind of horrific decline. We appear to be making vast tracts of land inhospitable to most forms of life, and are currently on course for ecological Armageddon. If we lose the insects then everything is going to collapse." (The Independent, Oct. 19, 2017)

Atlantic Ocean circulation at weakest point in 1,500 years

New research provides evidence that a key cog in the global ocean circulation system hasn't been running at peak strength since the mid-1800s and is currently at its weakest point in the past 1,600 years. If the system continues to weaken, it could disrupt weather patterns from the United States and Europe to the African Sahel, and cause more rapid increase in sea level on the US East Coast. Decline of the Atlantic Meridional Overturning Circulation (AMOC) is linked to the melting of Arctic sea ice and Greenland’s ice sheet. (Woods Hole Oceanographic Institution via ScienceDaily, April 11)

North American 'climate boundary' shifts

In 1878, the American geologist and explorer John Wesley Powell drew an invisible line in the dirt—a very long line. It was the 100th meridian west, the longitude he identified as the boundary between the humid eastern United States and the arid Western plains. Running south to north, the meridian cuts northward through the eastern states of Mexico, and on to Texas, Oklahoma, Kansas, Nebraska, the Dakotas, and the Canadian province of Manitoba on its way to the pole. Powell, best known for exploring the Grand Canyon and other parts of the West, was wary of large-scale settlement in that often harsh region, and tried convincing Congress to lay out water and land-management districts crossing state lines to deal with environmental constraints. Western political leaders hated the idea—they feared this might limit development, and their own power—and it never went anywhere. It was not the first time that politicians would ignore the advice of scientists.

Now, 140 years later, scientists are looking again at the 100th meridian. In two just-published papers, they examine how it has played out in history so far, and what the future may hold. They confirm that the divide has turned out to be very real, as reflected by population and agriculture on opposite sides. They say also that the line appears to be slowly moving eastward, due to climate change. They say it will almost certainly continue shifting in coming decades, expanding the arid climate of the western plains into what we think of as the Midwest. The implications for farming and other pursuits could be huge. (Earth Institute, Columbia University, April 11)

CO2 levels at highest in 800,000 years

From USA Today:

Carbon dioxide — the gas scientists say is most responsible for global warming — reached its highest level in recorded history last month, at 410 parts per million.

This amount is highest in at least the past 800,000 years, according to the Scripps Institute of Oceanography. Prior to the onset of the Industrial Revolution, carbon dioxide levels had fluctuated over the millennia but had never exceeded 300 parts per million.

“We keep burning fossil fuels. Carbon dioxide keeps building up in the air,” said Scripps scientist Ralph Keeling, who maintains the longest continuous record of atmospheric carbon dioxide on Earth. “It’s essentially as simple as that.”

We're a little confused about this, as a report of similar levels three years ago said they were the highest in 2 million years. These levels have been characterized as a point of no return.

Trump quietly cancels NASA's Carbon Monitoring System

The White House has mounted a broad attack on climate science, repeatedly proposing cuts to NASA's earth science budget, including the Carbon Monitoring System (CMS), and cancellations of climate missions such as the Orbiting Carbon Observatory 3 (OCO-3). Although Congress fended off the budget and mission cuts, a spending deal signed in March made no mention of the CMS. That allowed the administration's move to take effect, says Steve Cole, a NASA spokesperson. Cole says existing grants will be allowed to finish up, but no new research will be supported. (Science, May 9)

Antarctic ice loss has tripled in a decade

Antarctica’s ice sheet is melting at a rapidly increasing rate, now pouring more than 200 billion tons of ice into the ocean annually and raising sea levels a half-millimeter every year, a team of 80 scientists reported. 

The melt rate has tripled in the past decade, the study concluded. If the acceleration continues, some of the worst fears about rising oceans could be realized, leaving low-lying cities and communities with less time to prepare than they had hoped.

The result also reinforces that nations have a short window—perhaps no more than a decade—to cut greenhouse-gas emissions if they hope to avert some of the worst consequences of climate change.

Antarctica, the planet's largest ice sheet, lost 219 billion tons of ice annually from 2012 through 2017—approximately triple the 73 billion-ton melt rate of a decade ago. From 1992 through 1997, Antarctica lost 49 billion tons of ice annually.

The study is the product of a large group of Antarctic experts who collectively reviewed 24 recent measurements of Antarctic ice loss, reconciling their differences to produce the most definitive figures yet on changes in Antarctica. Their results—known formally as the "Ice Sheet Mass Balance Inter-Comparison Exercise" (IMBIE)—were published in the journal Nature. (WaPo, June 13)

'Hothouse Earth' scenario seen

From the BBC News, Aug. 6:

It may sound like the title of a low budget sci-fi movie, but for planetary scientists, "Hothouse Earth" is a deadly serious concept.

Researchers believe we could soon cross a threshold leading to boiling hot temperatures and towering seas in the centuries to come.

Even if countries succeed in meeting their CO2 targets, we could still lurch on to this "irreversible pathway."

Their study shows it could happen if global temperatures rise by 2C.

An international team of climate researchers, writing in the journal, Proceedings of the National Academy of Sciences, says the warming expected in the next few decades could turn some of the Earth's natural forces—that currently protect us—into our enemies....

Currently, global temperatures have risen about 1 degree above pre-industrial levels and they are rising by around 0.17C per decade.

In their new study the authors looked at 10 natural systems, which they term "feedback processes." Right now, these help humanity to avoid the worst impacts of carbon and temperature rises, and include forests, Arctic sea-ice, and methane hydrates on the ocean floor.

The worry is that if one of these systems tips over and starts pushing large amounts of CO2 into the atmosphere, the rest could follow like a row of dominoes.

According to the research paper, crossing into a Hothouse Earth period would see a higher global temperature than at any time in the past 1.2 million years.

The climate might stabilise with 4-5 degrees C of warming above the pre-industrial age. Thanks to the melting of ice sheets, the seas could be 10-60 metres higher than now.

Essentially, this would mean that some parts of the Earth would become uninhabitable.

The impacts would be "massive, sometimes abrupt and undoubtedly disruptive," say the authors.

The only upside, if you can call it that, is that the worst impacts may not be felt for a century or two. The downside is that we wouldn't really be able to do anything about it, once it starts.

UN chief: two years to avoid 'runaway' climate scenario

UN Secretary General António Guterres told global leaders this week: "If we do not change course by 2020, we risk missing the point where we can avoid runaway climate change. Climate change is the defining issue of our time, and we are at a defining moment,” he said. “Scientists have been telling us for decades. Over and over again. Far too many leaders have refused to listen." (The Hill)

We aren't sure where the 2020 date comes from... We could well be there already.

Trump orders California to keep polluting

The Trump administration will seek to revoke California’s authority to regulate automobile emissions—including its mandate for electric-car sales—in a proposed revision of Obama-era standards. (LAT, July 23) The news comes days after the California Air Resources Board announced that the state had hit its goal of bringing emissions to 1990 levels four years ahead of schedule. The drop came thanks to a boom in renewables and improvements in efficiency: The biggest reductions came from the electric power sector, where an increase in wind and solar energy has been displacing fossil fuels. (Grist, July 13) There are now fears some of this progress could be reversed due to the wildfires now raging in many areas of the state. (Times of San Diego, Aug. 11)

The Trump administration took the first steps Aug. 8 toward opening 1.6 million acres of public land in California to fracking and oil drilling, The Sacramento Bee reported. In a notice of intent published in the Federal Register, the Bureau of Land Management (BLM) said it will prepare an environmental impact statement on the use of fracking on 400,000 acres of public land and 1.2 million acres of mineral estate overseen by BLM in California counties including Fresno, San Luis Obispo and Santa Barbara. (EcoWatch, Aug. 9)

California law mandates 100% carbon-free energy by 2045

California Gov. Jerry Brown signed Senate Bill 100 into law on Sept. 10, which mandates a goal of a 100% renewable energy supply by 2045.

Brown said , "This bill and the executive order put California on a path to meet the goals of Paris and beyond. It will not be easy. It will not be immediate. But it must be done." The Public Utilities Commission (PUC) will implement a plan so that all energy suppliers in California are able to provide renewable energy and zero-carbon resources in increments over the next 25 years. In 2026 the state plans to achieve at least a 50% renewable benchmark, and then 60% by 2030. 

Last week Brown also signed legislation to block additional federal offshore drilling, in an open challenge to federal policy. (Jurist)

California to require solar energy in all new homes

The California Building Standards Commission approved a new rule Dec. 6 requiring that all homes built in California after 2020 have the capacity to produce and process solar energy. (Jurist)

Arctic's strongest sea ice breaks up for first time on record

The oldest and thickest sea ice in the Arctic has started to break up, opening waters north of Greenland that are normally frozen, even in summer. This phenomenon – which has never been recorded before – has occurred twice this year due to warm winds and a climate-change driven heatwave in the northern hemisphere. (The Guardian, Aug. 21)

NASA discovers bubbling lakes in the Arctic

From Forbes, Aug. 30:

NASA has released videos of bubbling lakes in the remote Arctic tundra, where warming continues to release greenhouse gases into the atmosphere at unprecedented rates.

The international research team, funded by NASA as part of their Arctic-Boreal Vulnerability Experiment (ABoVE), recently published their results in Nature Communications. What they found are bubbling lakes as greenhouse gases are released from the previously frozen ground, leading to increased greenhouse gas emissions and a warming positive feedback.

We've been warning for years that an Arctic methane fart could doom humanity.

We mean it.

Trump plan to weaken Obama-era methane testing rule

President Trump and the Environmental Protection Agency (EPA) on Sept. 11 announced a plan (PDF) to amend the 2016 New Source Performance Standards for the oil and gas industry that would weaken requirements for testing and monitoring methane gas emissions.

In March the EPA announced two amendments addressing the "fugitive emissions" requirements of the Emission Standards for New, Reconstructed, and Modified Sources. In the proposal for reconsideration, the EPA seeks to reduce monitoring of the larger sites in the Alaskan North Slope from semi-annual to annual, and to change monitoring frequency "at low-production well sites (well sites with less than 15 barrels of oil equivalent (BOE) per well per day)"* from semi-annual to biennial (every other year).

According to the press release, the proposed regulation will "streamline implementation, reduce duplicative EPA and state requirements, and significantly decrease unnecessary burdens on domestic energy producers." The regulation is estimated to save "approximately $484 million in regulatory costs from 2019 – 2025 or $75 million annually." (Jurist)

* Incorrect use of parentheses in original.

Antarctic warming could mean disastrous sea-level rise: study

From the Washington Post, July 21:

Temperatures not much warmer than the planet is experiencing now were sufficient to melt a major part of the East Antarctic ice sheet in Earth's past, scientists reported Wednesday, including during one era about 125,000 years ago when sea levels were as much as 20 to 30 feet higher...

"It doesn't need to be a very big warming, as long as it stays 2 degrees warmer for a sufficient time, this is the end game," said David Wilson, a geologist at Imperial College London and one of the authors of the new research, which was published in Nature...

The research concerns a little-studied region called the Wilkes Subglacial Basin, which is roughly the size of California and Texas combined and contains over 10 feet of potential sea-level rise. Fronted by three enormous glaciers named Cook, Mertz and Ninnis, the Wilkes is known to be vulnerable to fast retreat because the ice here is not standing on land and instead is rising up from a deep depression in the ocean floor.

Moreover, that depression grows deeper as you move from the current icy coastline of the Wilkes farther inland toward the South Pole, a downhill slope that could facilitate rapid ice loss.

What the new science adds is that during past warm periods in Earth's history, some or all of the ice in the Wilkes Subglacial Basin seems to have gone away. That's an inference researchers made by studying the record of sediments in the seafloor just off the coast of the current ice front...

Humans have caused about 1 degree Celsius (1.8 degrees Fahrenheit) of warming above the preindustrial planetary temperatures experienced before the year 1880 or so. The world has pledged to avoid a warming above 2 degrees Celsius, and even hopes to hold the warming to 1.5 degrees, but current promises made by countries are not nearly enough to prevent these outcomes.

In other words, we are already on a course that could heat the planet enough to melt some or all of the Wilkes Basin.

White House: we're doomed

From the Washington Post, Sept. 28:

Trump administration sees a 7-degree rise in global temperatures by 2100
Last month, deep in a 500-page environmental impact statement, the Trump administration made a startling assumption: On its current course, the planet will warm a disastrous seven degrees by the end of this century.

A rise of seven degrees Fahrenheit, or about four degrees Celsius, compared with preindustrial levels would be catastrophic, according to scientists. Many coral reefs would dissolve in increasingly acidic oceans. Parts of Manhattan and Miami would be underwater without costly coastal defenses. Extreme heat waves would routinely smother large parts of the globe.

But the administration did not offer this dire forecast, premised on the idea that the world will fail to cut its greenhouse gas emissions, as part of an argument to combat climate change. Just the opposite: The analysis assumes the planet's fate is already sealed.

The draft statement, issued by the National Highway Traffic Safety Administration (NHTSA), was written to justify President Trump’s decision to freeze federal fuel-efficiency standards for cars and light trucks built after 2020. While the proposal would increase greenhouse gas emissions, the impact statement says, that policy would add just a very small drop to a very big, hot bucket.

"The amazing thing they're saying is human activities are going to lead to this rise of carbon dioxide that is disastrous for the environment and society. And then they’re saying they’re not going to do anything about it," said Michael MacCracken, who served as a senior scientist at the U.S. Global Change Research Program from 1993 to 2002.

The document projects that global temperature will rise by nearly 3.5 degrees Celsius above the average temperature between 1986 and 2005 regardless of whether Obama-era tailpipe standards take effect or are frozen for six years, as the Trump administration has proposed. The global average temperature rose more than 0.5 degrees Celsius between 1880, the start of industrialization, and 1986, so the analysis assumes a roughly four degree Celsius or seven degree Fahrenheit increase from preindustrial levels.

White House: Science? We don't need no stinking science

From the New York Times, Sept. 27:

E.P.A. to Eliminate Office That Advises Agency Chief on Science
WASHINGTON — The Environmental Protection Agency plans to dissolve its Office of the Science Advisor, a senior post that was created to counsel the E.P.A. administrator on the scientific research underpinning health and environmental regulations, according to a person familiar with the agency's plans. The person spoke anonymously because the decision had not yet been made public.

The science adviser works across the agency to ensure that the highest quality science is integrated into the agency’s policies and decisions, according to the E.P.A.’s website. The move is the latest among several steps taken by the Trump administration that appear to have diminished the role of scientific research in policymaking while the administration pursues an agenda of rolling back regulations.

Asked about the E.P.A.'s plans, John Konkus, a spokesman for the agency, emailed a prepared statement from the science adviser, Jennifer Orme-Zavaleta, in which she described the decision to dissolve the office as one that would "combine offices with similar functions" and "eliminate redundancies."

Nature pushed to the brink by 'runaway consumption'

Unbridled consumption has decimated global wildlife, triggered a mass extinction and exhausted Earth's capacity to accommodate humanity's expanding appetites, the World Wildlife Fund warns in a new report. From 1970 to 2014, 60% of all animals with a backbone—fish, birds, amphibians, reptiles and mammals—were wiped out by human activity, according to WWF's Living Planet Report, based on an ongoing survey of more than 4,000 species spread over 16,700 populations scattered across the globe. (AFP)

Greenland ice sheet melt rate unprecedented

From the Daily News, Dec. 6:

Greenland's ice sheet is melting at a pace unprecedented in thousands of years, a study has found, and has in particular accelerated over the past two decades.

"I think the acceleration is the bell-ringer here," said Mary Albert, a glaciologist at Dartmouth University, to Nature.com. The study was published in the journal Nature.

Having stayed relatively stable for millennia, the ice-sheet melt rate is 50% higher than it was before the Industrial Revolution and 33% faster than it was in the 20th century, CNN reported.

Arctic warming poses 'rapid unraveling' of the region

From the NY Times:

Persistent warming in the Arctic is pushing the region into "uncharted territory" and increasingly affecting the continental United States, scientists said Tuesday.

"We're seeing this continued increase of warmth pervading across the entire Arctic system," said Emily Osborne, an official with the National Oceanic and Atmospheric Administration, who presented the agency’s annual assessment of the state of the region, the "Arctic Report Card."

The Arctic has been warmer over the last five years than at any time since records began in 1900, the report found, and the region is warming at twice the rate as the rest of the planet.

Dr. Osborne, the lead editor of the report and manager of NOAA's Arctic Research Program, said the Arctic was undergoing its "most unprecedented transition in human history."

In 2018, "warming air and ocean temperatures continued to drive broad long-term change across the polar region, pushing the Arctic into uncharted territory," she said at a meeting of the American Geophysical Union in Washington.

The rising air temperatures are having profound effects on sea ice, and on life on land and in the ocean, scientists said. The impacts can be felt far beyond the region, especially since the changing Arctic climate may be influencing extreme weather events around the world.

US carbon emissions surged in 2018

From the NY Times, Jan. 8:

WASHINGTON — America's carbon dioxide emissions rose by 3.4 percent in 2018, the biggest increase in eight years, according to a preliminary estimate published Tuesday.

Strikingly, the sharp uptick in emissions occurred even as a near-record number of coal plants around the United States retired last year, illustrating how difficult it could be for the country to make further progress on climate change in the years to come, particularly as the Trump administration pushes to roll back federal regulations that limit greenhouse gas emissions.

The estimate, by the research firm Rhodium Group, pointed to a stark reversal. Fossil fuel emissions in the United States have fallen significantly since 2005 and declined each of the previous three years, in part because of a boom in cheap natural gas and renewable energy, which have been rapidly displacing dirtier coal-fired power.

Yet even a steep drop in coal use last year wasn't enough to offset rising emissions in other parts of the economy. Some of that increase was weather-related: A relatively cold winter led to a spike in the use of oil and gas for heating in areas like New England.

But, just as important, as the United States economy grew at a strong pace last year, emissions from factories, planes and trucks soared. And there are few policies in place to clean those sectors up.

Antarctica losing ice six times faster today than in 1980s

Antarctica is melting more than six times faster than it did in the 1980s, a new study shows. Scientists used aerial photographs, satellite measurements and computer models to track how fast the continent has been melting since 1979 in 176 individual basins. Since 2009, Antarctica has lost almost 278 billion tons (252 billion metric tons) of ice per year, the study found. In the 1980s, it was losing 44 billion tons (40 billion metric tons) a year.

Eric Rignot, a University of California scientist, was the lead author on the study published in the Proceedings of the National Academy of Sciences. He said that his satellite-based study found East Antarctica, which used to be considered stable, is losing 56 billion tons (51 billion metric tons) of ice a year. (AP, Jan. 14)

Antarctic glacier collapse spells global disaster

An International Thwaites Glacier Collaboration group has launched a five-year project to study West Antarctica's Thwaites Glacier—the size of Great Britain and becoming unstable. Because of the nature of the bedrock underneath it, if Thwaites starts to collapse, it could go fast, contributing roughly two feet of global sea level rise in as little as 50 years. (Public Radio InternationaI, Jan. 23)

Scientists detect enormous cavity beneath Antarctica

gigantic cavity growing under West Antarctica that scientists say covers two-thirds the footprint of Manhattan and stands almost 300 metres (984 ft) tall.

This huge opening at the bottom of the Thwaites Glacier—a mass infamously dubbed the "most dangerous glacier in the world"—is so big it represents an overt chunk of the estimated 252 billion tonnes of ice Antarctica loses every year. 

Researchers say the cavity once held some 14 billion tons of ice. Even more disturbing, they say it lost most of this ice volume over the last three years alone.

"We have suspected for years that Thwaites was not tightly attached to the bedrock beneath it," says glaciologist Eric Rignot from the University of California, Irvine, and NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California. "Thanks to a new generation of satellites, we can finally see the detail." (Science Alert)

Greenland ice sheet approaches "tipping point"

Greenland's enormous ice sheet is melting at such an accelerated rate that it may have reached a "tipping point," and could become a major factor in sea-level rise around the world within two decades, scientists said in a new study for the Proceedings of the National Academy of Sciences. The authors found that ice loss in 2012 was nearly four times the rate in 2003, and after a lull in 2013-14, it has resumed. The lull was linked to the North Atlantic Oscillation, a periodic anomaly that has occurred throughout the historical record. (NYT, Jan. 23) As we've noted before the North Atlantic Oscillation itself could become destabilized due to the receding Greenland sea ice, with consequences that are still uncertain.... but are likely already seen.