Global Warming...New Report...and it ain't happy news

The climate summit in Glasgow was, in effect, Costa Rica’s Super Bowl, another chance to show off its impressive environmental credentials. It is the only tropical country that has successfully halted and reversed deforestation, a commitment dozens of others made at Cop26 but are far from achieving.

Some 1.3 million people worldwide already work in the wind sector, but five times as many will be needed as the shift to renewable energy gathers pace. Job prospects are increasing as the sector picks up worldwide.

What wind power does is kill birds.

Young Earth creationism, scientists portrayed as part of an anti-Christian conspiracy, environmentalists viewed with extreme suspicion. Growing up as an evangelical within the world of the US Christian Right, and attending Christian schools, I know first-hand how extreme they are, and how aggressive in their defence of “alternative facts”.

Understanding this is important while COP26 (the twenty-sixth annual Conference of the Parties to the United Nations Framework Convention on Climate Change) is under way in Glasgow. Because the Republicans who just won off-year elections (which bodes ill for the midterm congressional elections in 2022), along with ex-president Donald Trump, represent the culmination of a decades-long process of radicalisation in their party driven by the thoroughly authoritarian Christian Right.

This isn’t your grandparents’ Republican Party. At least ten GOP members who were elected to office just this week attended Trump’s ‘Stop the Steal’ rally on 6 January. Aiming to keep president-elect Biden from taking office by pushing outright lies about supposed election fraud, that rally culminated in a violent insurrection against the federal government. Christian symbols and prayers were a ubiquitous feature of the events of that notorious day.

God will solve the climate crisis

The Christian Right’s views on the environment are extremely worrying. Consider, for a moment, the following actual quotations from national-level US legislators – all Republicans – on climate change.

Illinois representative John Shimkus, in the Year of our Lord 2010, cited a literal interpretation of the Noah’s ark story as evidence that concern over climate change was misplaced. “I do believe that God said the Earth would not be destroyed by a flood,” Shimkus said.

In office since 1997, he retired last year and was replaced in the House of Representatives by another Republican, Mary Miller. A born-again Sunday-school teacher and Christian homeschooling advocate, Miller achieved instant infamy when she declared “Hitler was right” about the importance of indoctrinating children in an impassioned speech at the ‘Stop the Steal’ rally.

Miller, as you would expect, is opposed to what she calls “radical ideas like the Green New Deal and other extreme environmental legislation”.

Senator James Inhofe from Oklahoma (in office since 1994) infamously carried a snowball on to the Senate floor in 2015 as a ‘gotcha’ meant to ‘disprove’ global warming. Oh, and he’s also compared the federal Environmental Protection Agency to the Gestapo.

“God’s still up there. The arrogance of people to think that we, human beings, would be able to change what He is doing in the climate is to me outrageous,” is something he said in 2012.

Michigan representative Tim Walberg said this about climate change, in 2017: “As a Christian, I believe that there is a creator in God who is much bigger than us. And I’m confident that, if there’s a real problem, he can take care of it.”

I grew up surrounded by this sort of rhetoric, and worse. For example, assertions that we don’t need to act to save the environment because Christ will be returning soon anyway.

To be sure, as the destruction wrought by climate change becomes more and more difficult to deny, Republicans turn increasingly to economic arguments as they attempt to keep us from seriously addressing the issue. But their attitudes, and those of their voter base, remain the same.

Democracy in crisis

Despite a majority of Americans disagreeing with them on almost everything, Republicans hold disproportionate power in the US for structural reasons – and the current Democratic leadership has not seized this moment to press through reforms that could make US politics more fair and democratic.

Republicans regularly support racist voter suppression initiatives at state level, and they have pushed through a slew of such measures in reaction to President Biden’s election. As a result, because the president is elected indirectly by the states via the electoral college rather than directly by the people, Republicans can – and, these days, often do – win the presidency while losing the popular vote.

The Democratic Party is the only major party in which most elected members at least make an effort to pursue pro-environment policies. But they are likely to lose control of Congress in the 2022 midterm elections.

It is also entirely possible that the Democrats will lose the presidency in 2024. Trump himself may end up back in office; he remains the authoritarian figure to whom rank-and-file Republicans look for leadership. Even if he doesn’t, another Republican president may well initiate the US’s withdrawal from the Paris accords (again), as Trump did, and for which Biden publicly apologised at COP26.

American democracy is in serious crisis. As long as that’s the case, the US simply cannot be counted on to act responsibly on the world stage with any consistency.

I don’t know how to solve the problem of getting reforms that would make the US more democratic, given that the Republicans – who stand to lose power in such a scenario – currently hold enough power to prevent most of the necessary reforms from being passed.

Today’s authoritarian Republicans, who have essentially merged with the Christian Right, are clearly willing to choose power over democracy and to reject or ignore any science that stands in the way of their agenda.

But the first step, it seems to me, is to raise awareness among the public, at home and abroad, in the hope that public outcry and pressure may start to make the kind of difference that leads to better political outcomes.

Undoubtedly, it will take more than a functioning, democratic United States to resolve the climate crisis. However, without a functioning, democratic United States playing its part, it seems unlikely that the world will be able to resolve the climate crisis at all.

A new, Yale-led study suggests the 21st century will see an expansion of hurricanes and typhoons into mid-latitude regions, which includes major cities such as New York, Boston, Beijing, and Tokyo.

Writing in the journal Nature Geoscience, the study's authors said tropical cyclones—hurricanes and typhoons—could migrate northward and southward in their respective hemispheres, as the planet warms as a result of anthropogenic greenhouse gas emissions. 2020's subtropical storm Alpha, the first tropical cyclone observed making landfall in Portugal, and this year's Hurricane Henri, which made landfall in Connecticut, may be harbingers of such storms.

"This represents an important, under-estimated risk of climate change," said first author Joshua Studholme, a physicist in Yale's Department of Earth and Planetary Sciences in the Faculty of Arts and Sciences, and a contributing author on the United Nations' Intergovernmental Panel on Climate Change sixth assessment report published earlier this year.

"This research predicts that the 21st century's tropical cyclones will likely occur over a wider range of latitudes than has been the case on Earth for the last 3 million years," Studholme said.

Co-authors of the study are Alexey Fedorov, a professor of oceanic and atmospheric sciences at Yale, Sergey Gulev of the Shirshov Institute of Oceanology, Kerry Emanuel of the Massachusetts Institute of Technology, and Kevin Hodges of the University of Reading.

While an increase in tropical cyclones is commonly cited as a harbinger of climate change, much remains unclear about how sensitive they are to the planet's average temperature. In the 1980's, study co-author Emanuel used concepts from classical thermodynamics to predict that global warming would result in more intense storms—a prediction that has been validated in the observational record.

Yet other aspects of the relationship between tropical cyclones and climate still lack physically based theory. For example, there is no agreement among scientists about whether the total number of storms will increase or decrease as the climate warms, or why the planet experiences roughly 90 such events each year.

"There are large uncertainties in how tropical cyclones will change in the future," said Fedorov. "However, multiple lines of evidence indicate that we could see more tropical cyclones in mid-latitudes, even if the total frequency of tropical cyclones does not increase, which is still actively debated. Compounded by the expected increase in average tropical cyclone intensity, this finding implies higher risks due to tropical cyclones in Earth's warming climate."

Typically, tropical cyclones form at low latitudes that have access to warm waters from tropical oceans and away from the shearing impact of the jet streams—the west-to-east bands of wind that circle the planet. Earth's rotation causes clusters of thunderstorms to aggregate and spin up to form the vortices that become tropical cyclones. Other mechanisms of hurricane formation also exist.

As the climate warms, temperature differences between the Equator and the poles will decrease, the researchers say. In summer months, this may cause weakening or even a split in the jet stream, opening a window in the mid-latitudes for tropical cyclones to form and intensify.

For the study, Studholme, Fedorov, and their colleagues analyzed numerical simulations of warm climates from Earth's distant past, recent satellite observations, and a variety of weather and climate projections, as well as the fundamental physics governing atmospheric convection and planetary-scale winds. For example, they noted that simulations of warmer climates during the Eocene (56 to 34 million years ago) and Pliocene (5.3 to 2.6 million years ago) epochs saw tropical cyclones form and intensify at higher latitudes.

"The core problem when making future hurricane predictions is that models used for climate projections do not have sufficient resolution to simulate realistic tropical cyclones," said Studholme, who is a postdoctoral fellow at Yale. "Instead, several different, indirect approaches are typically used. However, those methods seem to distort the underlying physics of how tropical cyclones form and develop. A number of these methods also provide predictions that contradict each other."

The new study derives its conclusions by examining connections between hurricane physics on scales too small to be represented in current climate models and the better-simulated dynamics of Earth's jet streams and north-south air circulation, known as the Hadley cells.

Global heating continued unabated with extreme weather rife and greenhouse gases hitting new highs

The last seven years were the world’s hottest on record, with the first analysis of global temperature in 2021 showing it was 1.2C above pre-industrial levels.

The assessment of the year, by the European climate agency Copernicus, also found carbon dioxide in the atmosphere reached record levels and that the potent greenhouse gas methane surged “very substantially”, also to a new record.

The rise in greenhouse gas concentration means more heat is being trapped than ever before but 2021 ranked as the fifth hottest year on record. This is because a natural and cyclic climate phenomenon called La Niña exerted a cooling influence by bringing cold Pacific waters to the surface.



The climate crisis continued unabated with extreme weather striking across the world. Europe suffered its hottest summer on record and broke its maximum temperature record in Sicily with 48.8C, while intense wildfires raged in Italy, Greece and Turkey. Severe floods made up to nine times more likely by global heating also wreaked havoc in Germany and Belgium

Extreme heat also caused the “mother of all heatwaves” in the west of the US and Canada. Temperature records were smashed by 5C and scientists calculated the event was made at least 150 times more likely by global heating. In California, the Dixie wildfire was the second largest in history.

China’s meteorological agency recently announced that 2021 was the country’s hottest year on record and that its northern region had its wettest year, with extreme weather widespread. Floods in July in Henan province caused hundreds of deaths.

Mauro Facchini, the head of Earth observation for the European Commission, said: “The 2021 analysis is a reminder of the continued increase in global temperatures and the urgent necessity to act.” The Copernicus data shows 21 of the 22 hottest years have come since the year 2000.

“The [extreme weather] events in 2021 are a stark reminder of the need to change our ways, take decisive and effective steps toward a sustainable society,” said Carlo Buontempo, director of the Copernicus climate service.

The average CO2 levels in 2021 reached a new record of 414 parts per million in 2021 – before the Industrial Revolution and large scale burning of fossil fuels the level was 280ppm. The rate of CO2 rise remained the same as it had since 2010, despite Covid-related lockdowns.

Methane levels are accelerating with the growth rate in 2021 approximately three times the rate of a decade ago. Methane is emitted through fossil fuel exploitation, cattle and other livestock, and natural wetland processes and scientists are uncertain about the cause of the rapid rises.

Vincent-Henri Peuch, at Copernicus, said: “CO2 and methane concentrations are continuing to increase year-on-year and without signs of slowing down.

Prof Rowan Sutton, at the University of Reading, UK, said: “At a global level the warming may appear gradual but it is the impact on extreme events in many different parts of the world that is dramatic. We should see the record breaking 2021 events, such as the heatwave in Canada and floods in Germany, as a punch in the face to make politicians and public alike wake up to the urgency of the climate emergency.”

Other temperature datasets for 2021 will be published in coming weeks by the UK and Japanese Met Offices and Nasa and Noaa in the US, with similar results expected.

In 2021, natural disasters caused overall losses of US$ 280bn, of which roughly US$ 120bn were insured

Alongside 2005 and 2011, the year 2021 proved to be the second-costliest ever for the insurance sector (record year 2017: US$ 146bn, inflation-adjusted) – overall losses from natural disasters were the fourth-highest to date (record year 2011: US$ 355bn)

Hurricane Ida was the year’s costliest natural disaster, with overall losses of US$ 65bn (insured losses of US$ 36bn)

In Europe, flash floods after extreme rainfall caused losses of US$ 54bn (€46bn) – the costliest natural disaster on record in Germany

Many of the weather catastrophes fit in with the expected consequences of climate change, making greater loss preparedness and climate protection a matter of urgency

The world’s oceans have been set to simmer, and the heat is being cranked up. Last year saw the hottest ocean temperatures in recorded history, the sixth consecutive year that this record has been broken, according to new research.

The heating up of our oceans is being primarily driven by the human-caused climate crisis, scientists say, and represents a starkly simple indicator of global heating. While the atmosphere’s temperature is also trending sharply upwards, individual years are less likely to be record-breakers compared with the warming of the oceans.

Last year saw a heat record for the top 2,000 meters of all oceans around the world, despite an ongoing La Niña event, a periodic climatic feature that cools waters in the Pacific. The 2021 record tops a stretch of modern record-keeping that goes back to 1955. The second hottest year for oceans was 2020, while the third hottest was 2019.



“The ocean heat content is relentlessly increasing, globally, and this is a primary indicator of human-induced climate change,” said Kevin Trenberth, a climate scientist at the National Center for Atmospheric Research in Colorado and co-author of the research, published in Advances in Atmospheric Sciences.

Warmer ocean waters are helping supercharge storms, hurricanes and extreme rainfall, the paper states, which is escalating the risks of severe flooding. Heated ocean water expands and eats away at the vast Greenland and Antarctic ice sheets, which are collectively shedding around 1tn tons of ice a year, with both of these processes fueling sea level rise.

Oceans take up about a third of the carbon dioxide emitted by human activity, causing them to acidify. This degrades coral reefs, home to a quarter of the world’s marine life and the provider of food for more than 500m people, and can prove harmful to individual species of fish.

As the world warms from the burning of fossil fuels, deforestation and other activities, the oceans have taken the brunt of the extra heat. More than 90% of the heat generated over the past 50 years has been absorbed by the oceans, temporarily helping spare humanity, and other land-based species, from temperatures that would already be catastrophic.

The amount of heat soaked up by the oceans is enormous. Last year, the upper 2,000 meters of the ocean, where most of the warming occurs, absorbed 14 more zettajoules (a unit of electrical energy equal to one sextillion joules) than it did in 2020. This amount of extra energy is 145 times greater than the world’s entire electricity generation which, by comparison, is about half of a zettajoule.

Long-term ocean warming is strongest in the Atlantic and Southern oceans, the new research states, although the north Pacific has had a “dramatic” increase in heat since 1990 and the Mediterranean Sea posted a clear high temperature record last year.

The heating trend is so pronounced it’s clear to ascertain the fingerprint of human influence in just four years of records, according to John Abraham, another of the study’s co-authors. “Ocean heat content is one of the best indicators of climate change,” added Abraham, an expert in thermal sciences at University of St Thomas.

“Until we reach net zero emissions, that heating will continue, and we’ll continue to break ocean heat content records, as we did this year,” said Michael Mann, a climate scientist at Penn State University and another of the 23 researchers who worked on the paper. “Better awareness and understanding of the oceans are a basis for the actions to combat climate change.”

A new report has revealed that a record number of Americans are now alarmed about the climate crisis.

The study, published by the Yale Program on Climate Change Communication, found that Americans overall are becoming increasingly worried about global heating, more engaged with the issue and more supportive of finding solutions to the issue.
[...]
The study revealed that the largest group, Alarmed (33%) greatly outnumber the dismissive (9%) by more than three to one. Approximately six in 10 Americans (59%) are either Alarmed or Concerned while only approximately two in 10 (19%) are Doubtful or Dismissive.
... ... ...

Within the brutal machinations of US politics, Joe Manchin has been elevated to a status of supreme decision-maker, the man who could make or break Joe Biden’s presidency.

Internationally, however, the Democratic senator’s new fame has been received with puzzlement and growing bitterness, as countries already ravaged by the climate crisis brace themselves for the US – history’s largest ever emitter of planet-heating gases – again failing to pass major climate legislation.

For six months, Manchin has refused to support a sweeping bill to lower emissions, stymieing its progress in an evenly split US Senate where Republicans uniformly oppose climate action. Failure to pass the Build Back Better Act risks wounding Biden politically but the ramifications reverberate far beyond Washington, particularly in developing countries increasingly at the mercy of disastrous climate change.

“He’s a villain, he’s a threat to the globe,” said Saleemul Huq, director of the International Centre for Climate Change and Development, based in Bangladesh. “If you talk to the average citizen in Dhaka, they will know who Joe Manchin is. The level of knowledge of American politics here is absolutely amazing, we know about the filibuster and the Senate and so on.

“What the Americans do or don’t do on climate will impact the world and it’s incredible that this one coal lobbyist is holding things up. It will cause very bad consequences for us in Bangladesh, unfortunately.”

The often tortuous negotiations between Manchin, the White House and Democratic leaders appeared doomed on 19 December when the West Virginia senator said he could not support the $1.75tn bill, citing concerns over inflation and the national debt. The latest twist caused anguish to those who see their futures being decided by a previously obscure politician located thousands of miles away.

“I’ve been following the situation closely,” said Tina Stege, climate envoy for the Marshall Islands, a low-lying Pacific nation that risks being wiped out by rising sea levels. “We have to halve emissions in this decade and can’t do it without strong, immediate action by the US.”

Stege said the Marshall Islands was already suffering the impacts of the climate crisis and if the US doesn’t slash its emissions “the outcomes for countries like mine are unthinkable.”

Even America’s closest allies have looked on in dismay as a single lawmaker from Biden’s own party has stalled what would be the biggest – and arguably first – piece of climate legislation in the US’s plodding, and often rancorous, history of dealing with escalating global heating.

“Biden has done a fair bit in very challenging circumstances [but] in Canada we look on with bewilderment because it’s such a different political context. It’s very bizarre,” said Catherine McKenna, who was environment minister in Justin Trudeau’s government that introduced carbon pricing in 2019. “Politics is hard but I don’t think anyone has given up. We just really hope they are able to get a deal.”

McKenna said she was vilified by some Canadian provincial premiers who “fought to the death” against carbon pricing but that there was now broader support for climate action across the country, including within industry, than in the US. “It’s unfortunate that it’s just one person that is holding up something that’s so critically important,” she said of Manchin.

“Joe Manchin is a problem, and I think he needs to be called out,” said Ed Davey, a British MP who was previously the UK’s secretary of state for energy and climate change. “It’s in the US interest, in the interest of West Virginia and elsewhere, to take advantage of green zero-carbon technology, which is the future.”

Davey, who is now leader of the Liberal Democrats, warned that the US risks ceding leadership in clean energy to China if it doesn’t act. “People will end up paying higher prices, jobs will go and not be created, the security of America will be reduced, Beijing will be laughing,” he said, adding that Manchin was in effect “working on behalf of the Chinese government” by not supporting the transition away from fossil fuels.

China used last year’s Cop26 climate talks in Scotland to “insidiously point out to every country that US just can’t implement”, said Rachel Kyte, an expert in international affairs at Tufts University and a climate adviser to the UN secretary general. Kyte said many governments believe Biden is well-meaning but cannot follow through on his commitments, a frustration compounded by a lack of American action on related areas, such as climate finance for poorer countries.

“There’s almost a resentment that the US just can’t deliver,” she added. “There’s this sinking feeling about the politics of America. You can’t turn your back on the US because it’s still the biggest economy, but what are countries supposed to do?”

Much of this angst is now being channeled towards Manchin.

After more than a decade in national politics, the 74-year-old senator has suddenly garnered a level of infamy far beyond his fiefdom of West Virginia, where the centrist Democrat has served as governor and senator while reaping millions of dollars through his personal investments and campaign contributions from a coal industry that continues to loom large in his state. It’s a situation that has caused bafflement overseas.
Young demonstrators take part during a climate change strike in Dhaka, Bangladesh, to demand that world leaders be imprisoned for not taking environmental measures that affect the world.

“Who is Manchin, the Dem senator from West Virginia who betrayed Biden?” La Repubblica in Italy has demanded. Clarín, a newspaper in Argentina, has called Manchin a “rebelde” and a “tycoon with ties to the mining structure of West Virginia, the other Virginia of the USA”. Helsingin Sanomat, a Finnish newspaper, also noted Manchin’s links to the fossil fuel industry and lamented that he has “disagreed with the most ambitious climate action” put forward by the US.

The negotiations with Manchin involve stakes far greater than any normal political maneuvering in Washington. The world is already being strafed by wildfires, heatwaves, floods and societal instability wrought by the climate crisis and rising temperatures are on track to breach limits set by governments in the Paris climate accords, a situation that would push some parts of the world beyond human livability.

Salvaging this situation will be virtually impossible without swift action by the US, the world’s second largest carbon polluter and a major oil and gas exporter. Analysts say the half a trillion dollars of support for renewable energy and electric cars in the Build Back Better bill would give the US a decent chance of cutting its emissions in half this decade, which Biden and scientists say is imperative to avoid climate breakdown.

But Manchin’s opposition has already ensured the removal of a key element of the bill, a plan to force utilities to phase in clean energy over time, and the prospect of him joining Republicans to block the overall package has seen him come under intense criticism within the US.

Climate activists have confronted Manchin in Washington and kayaked to his yacht to remonstrate with him. Some fellow Democrats say he has “failed the American people”. Even the Sunday Gazette, the local paper of Charleston, West Virginia, has run a headline of ‘We need this so bad’, in reference to the bill.

All this has been to little effect, although Manchin did say earlier this month there could still be agreement on “the climate thing”, offering some vague hope to activists while not quite quelling their anger. “Senator Manchin is a fossil-fueled sociopath on a Maserati joyride while he lets the world burn,” said Janet Redman, climate campaign director at Greenpeace USA. “At the end of the day, Manchin cares less about his constituents than he does about the fossil fuel industry.”

The current, floundering attempt to pass climate legislation is a grimly familiar episode in a lengthy record of American inadequacy. Donald Trump donned a coal miner’s helmet on the campaign trail and removed the US from the Paris climate deal. Barack Obama failed to get cap-and-trade legislation past a recalcitrant Congress. George W Bush rejected the Kyoto climate accords. In 1993, a previous Democratic senator from West Virginia, Robert Byrd, blocked a Bill Clinton plan to tax carbon emissions.

Manchin is, in some respects, a “fall guy” for a deeper American political dysfunction over the climate crisis, Kyte said. “If Republicans weren’t in the lock-grip of certain vested interests, if they had a policy on climate adaptation or green jobs for the future, Joe Manchin wouldn’t have the influence he has,” she said.

President Barack Obama wipes perspiration from his face as he speaks about climate change at Georgetown University in Washington in 2013. Despite signing up to the Paris climate accord he failed to pass major climate crisis legislation. Photograph: Charles Dharapak/AP

“Joe Manchin has become the personification of a problem and removing him doesn’t solve it,” Kyte added. “It doesn’t give us a bipartisan agreement of the danger we are in. A political culture that allows you to enrich yourself and your family from industries you regulate and not declare a conflict of interest lies beyond Joe Manchin, it’s bigger than just him.”

Even if American political inertia hasn’t changed, the world certainly has – the last seven years were the planet’s hottest on record, cataclysmic wildfires are now year-round events in the US west and deadly flooding swamps basements in New York, picturesque towns in Germany and subways in China. There is mounting fear that the world, including the US, does not have the time for yet another futile American effort to address the unraveling climate crisis.

“Unfortunately, politicians getting fossil fuel money are standing in the way and sacrificing the rest of us once again,” said Vanessa Nakate, a climate justice activist from Uganda. Nakate pointed out that Africa was suffering from climate change even though it is responsible for just a small fraction of global emissions.

“We are so reliant on the choices others make,” she said. “Our lives are literally in their hands.”

Perhaps you remember iceberg A68a, which enjoyed a few minutes of fame back in 2017 when it broke off an ice shelf on the Antarctic Peninsula. Hardly your everyday iceberg, it was one of the biggest ever seen, more than 100 miles long and 30 miles wide.

The iceberg drifted slowly through the icy Weddell Sea for a few years, before picking up steam as it entered the Southern Ocean. When last we heard from it, in 2020, it was bearing down on the island of South Georgia in the South Atlantic, a bit shrunken and battered from a journey of more than a thousand miles.

Alas, ol’ A68a is no more. Last year, some 100 miles from South Georgia, it finally did what all icebergs eventually do: thinned so much that it broke up into small pieces that eventually drifted off to nothingness.

In its prime, A68a was nearly 800 feet thick, though all but 120 feet of that was hidden below the waterline.

Ecologists and others had feared that during its journey the iceberg might become grounded near South Georgia. That could have kept the millions of penguins and seals that live and breed there from reaching their feeding areas in the ocean.

That didn’t happen. New research shows that A68a performed more of a drive-by and most likely only struck a feature on the seafloor briefly as it turned and kept going until it broke up.

But the research also revealed another potential threat from the iceberg to ecosystems around South Georgia. As it traveled through the relatively warm waters of the Southern Ocean into the South Atlantic, it melted from below, eventually releasing a huge quantity of fresh water into the sea near the island. The influx of so much fresh water could affect plankton and other organisms in the marine food chain.

The scientists, led by Anne Braakmann-Folgmann, a doctoral student at the Center for Polar Observation and Modeling at the University of Leeds in Britain, used satellite imagery to monitor the shape and location of the iceberg over the course of its journey. (Like other large Antarctic icebergs, it was named according to a convention established by the U.S. National Ice Center, which is a bit less flashy than the one used for hurricanes.)

The imagery showed how the area of the iceberg changed over time. The researchers also determined its thickness using data from satellites that measure ice height. By the time it broke up, Ms. Braakmann-Folgmann said, A68a was more than 200 feet thinner overall.

A68a left its mark. The researchers, whose findings were published in the journal Remote Sensing of Environment, estimated that melting in the vicinity of South Georgia resulted in the release of about 150 billion tons of fresh water. That’s enough to fill an Olympic-size swimming pool 61 million times over, the researchers said, although because the ice was already floating its melting did not contribute to sea-level rise.

Not only is the water fresh, not salty, but it also contains a large amount of iron and other nutrients. Ms. Braakmann-Folgmann is helping another group of researchers, from the British Antarctic Survey, who are trying to determine the ecological effects of the iceberg and the meltwater.

When the iceberg was near South Georgia, scientists with the survey were able to deploy autonomous underwater gliders to take water samples. On the island, they used tracking devices on some gentoo penguins and fur seals, to see whether the presence of the iceberg affected their foraging behavior.

Geraint Tarling, a biological oceanographer with the survey, said that preliminary findings from the tracking data showed that the penguins and seals did not alter foraging routes, as they might have had the iceberg blocked their way or affected their prey.

“At least in the areas of the colonies that we saw, the impacts from the iceberg itself are not as devastating as we first feared,” Dr. Tarling said.

But there is still much data to analyze, Dr. Tarling suggested, especially the water samples. A large influx of fresh water on the surface could affect the growth of phytoplankton, at the lower end of the food change, or it could alter the mix of phytoplankton species available, he said.

Complicating the analysis is that 2020, when the iceberg was nearing South Georgia, also happened to be a bad year for krill, the small crustaceans that are just above phytoplankton in the food chain.

Dr. Tarling said that although A68a did not become grounded, a few other large icebergs have in recent decades. Grounding and dragging of an iceberg can wreak havoc on ecosystems on or near the seafloor, he said.

And climate change could potentially lead to more grounding episodes. Warming is causing parts of the huge Antarctic ice sheets to flow faster toward the ocean, leading to more calving of icebergs that then travel north.

“What we’re looking at is a lot more movement of icebergs that could actually gouge these areas of the sea floor,” Dr. Tarling said.

Abstract
Mountain glacier systems are decreasing in volume worldwide yet relatively little is known about their upper reaches (>5000 m). Here we show, based on the world’s highest ice core and highest automatic weather stations, the significant and increasing role that melting and sublimation have on the mass loss of even Mt. Everest’s highest glacier (South Col Glacier, 8020 m). Estimated contemporary thinning rates approaching ~2 m a−1 water equivalent (w.e.) indicate several decades of accumulation may be lost on an annual basis now that glacier ice has been exposed. These results identify extreme sensitivity to glacier surface type for high altitude Himalayan ice masses and forewarn of rapidly emerging impacts as Mt. Everest’s highest glacier appears destined for rapid retreat.