The World Was Cooler In 2021 Than 2020. That’s Not Good News.

2021 was actually cooler than 2020, points out Wired science journalist Matt Simon. So is that good news?

No.
One reason for cooler temperatures in 2021 was likely La Niña, a band of cold water in the Pacific. It’s the product of strong trade winds that scour the ocean, pushing the top layer of water toward Asia, causing deeper, colder waters to rush to the surface to fill the void. This in turn influences the atmosphere, for instance changing the jet stream above the United States and leading to more hurricanes in the Atlantic. The sea itself cools things off by absorbing heat from the atmosphere.

The Covid-19 pandemic may have had an additional influence, but not in the way you might think. As the world locked down in 2020, fewer emissions went into the sky, including aerosols that typically reflect some of the sun’s energy back into space. “If you take them away, you make the air cleaner, then that’s a slight warming impact on the climate,” said Gavin Schmidt, director of NASA’s Goddard Institute for Space Studies, during a Thursday press conference announcing the findings. But as economic activity ramped back up in 2021, so did aerosol pollution, contributing again to that cooling effect. The 2021 temperature drop “may be possibly due to a resumption of activity that produces aerosols in the atmosphere,” Schmidt said…

Today’s findings are all the more alarming precisely because 2021 managed to overcome these cooling effects and still tally the sixth-highest temperature. And while global temperatures were cooler in 2021 than the year before, last year 1.8 billion people lived in places that experienced their hottest temperatures ever recorded, according to a report released today by Berkeley Earth. This includes Asian countries like China and North and South Korea, African nations like Nigeria and Liberia, and in the Middle East places like Saudi Arabia and Qatar. “We talk a lot about global average temperatures, but no one lives in the global average,” says Zeke Hausfather, a research scientist at Berkeley Earth. “In fact most of the globe, two-thirds of it, is ocean, and no one lives in the ocean — or very few people at least. And land areas, on average, are warming much faster than the rest of the world….”

Last summer in western Canada and the US Pacific Northwest, absurd temperatures of over 120 degrees Fahrenheit killed hundreds of people. According to Hausfather, the heat wave in Portland, Oregon, would have been effectively impossible without climate change, something like a once-every-150,000-year event.
It’s a fascinating article, that looks at trouble spots like Antarctica’s sea level-threatening “Doomsday Glacier” and a warming Gulf of Mexico, mapping the intensity of 2021’s temperature anomalies along with trend graphs for both global temperatures and land-vs-ocean averages. It touches on how climate change is impacting weather — everything from rain and floods to wildfires and locusts — as Bridget Seegers, an oceanographer at NASA, points out that “Extremes are getting worse. People are losing their homes and their lives and air quality, because the wildfires are bad.”
But Seegers somehow arrives at a positive thought. “There’s just a lot going on, and I want people to also feel empowered that we understand the problem. It’s just this other issue of deciding to take collective action….

“There’s a lot of reasons for optimism. We’re in charge. This would be a lot worse if we’re like, ‘Oh, it’s warming because we’re heading toward the sun, and we can’t stop it.'”

(Thanks to Slashdot reader Sanja Pantic for sharing the article!)

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World’s Largest Fish Breeding Grounds Found Under the Antarctic Ice

sciencehabit shares a report from Science.org: The most extensive and densely populated breeding colony of fish anywhere lurks deep underneath the ice of the Weddell Sea, scientists aboard an Antarctic research cruise have discovered. The 240 square kilometers of regularly spaced icefish nests, east of the Antarctic Peninsula, has astonished marine ecologists. “We had no idea that it would be just on this scale, and I think that’s the most fantastic thing,” says Mark Belchier, a fish biologist with the British Antarctic Survey and the government of South Georgia & the South Sandwich Islands, who was not involved in the new work.

In February 2021, the RV Polarstern — a large German research ship — was breaking through sea ice in the Weddell Sea to study marine life. While towing video cameras and other instruments half a kilometer down, near the sea floor, the ship came upon thousands of 75-centimeter-wide nests, each occupied by a single adult icefish — and up to 2100 eggs. “It was really an amazing sight,” says deep-sea biologist Autun Purser of the Alfred Wegener Institute, who led the ship’s underwater imaging. Sonar revealed nests extending for several hundred meters, like a World War I battlefield scarred by miniature craters. High-resolution video and cameras captured more than 12,000 adult icefish (Neopagetopsis ionah). The fish, which grow to about 60 centimeters, are adapted to life in the extreme cold. They produce antifreezelike compounds, and — thanks to the region’s oxygen-rich waters — are among the only vertebrates to have colorless, hemoglobin-free blood.

Including three subsequent tows, the team on the RV Polarstern saw 16,160 closely packed fish nests, 76% of which were guarded by solitary males. Assuming a similar density of nests in the areas between the ship’s transects, the researchers estimate that about 60 million nests cover roughly 240 square kilometers, they report today in Current Biology. Because of their sheer numbers, the icefish and their eggs are likely key players in the local ecosystem. […] The vast colony, the researchers say, is a new reason to create a marine protected area in the Weddell Sea, an idea has been proposed five out of the past 6 years to the intergovernmental treaty organization that regulates fisheries there.

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Himalayan Glaciers Are Melting at Furious Rate, New Study Shows

Glaciers across the Himalayas are melting at an extraordinary rate, with new research showing that the vast ice sheets there shrank 10 times faster in the past 40 years than during the previous seven centuries. From a report: Avalanches, flooding and other effects of the accelerating loss of ice imperil residents in India, Nepal and Bhutan and threaten to disrupt agriculture for hundreds of millions of people across South Asia, according to the researchers. And since water from melting glaciers contributes to sea-level rise, glacial ice loss in the Himalayas also adds to the threat of inundation and related problems faced by coastal communities around the world. “This part of the world is changing faster than perhaps anybody realized,” said Jonathan Carrivick, a University of Leeds glaciologist and the co-author of a paper detailing the research published Monday in the journal Scientific Reports. “It’s not just that the Himalayas are changing really fast, it’s that they’re changing ever faster.”

Scientists have long observed ice loss from large glaciers in New Zealand, Greenland, Patagonia and other parts of the world. But ice loss in the Himalayas is especially rapid, the new study found. The researchers didn’t pinpoint a reason but noted that regional climate factors, such as shifts in the South Asian monsoon, may play a role. The new finding comes as there is scientific consensus that ice loss from glaciers and polar ice sheets results from rising global temperatures caused by greenhouse-gas emissions from the burning of fossil fuels. Many peer-reviewed scientific studies have identified human activity as a cause of rising global temperatures. So did a report issued in August by the United Nations Intergovernmental Panel on Climate Change, which said “human influence is very likely the main driver of the global retreat of glaciers since the 1990s.” For the new study, Dr. Carrivick and his colleagues scanned satellite photos of almost 15,000 glaciers in the region for signs of the large ridges of rock and debris that glaciers leave behind as they slowly grind their way through the valleys. Using the locations of these ancient glacial tracks, the scientists estimated the span of ice sheet coverage in previous centuries.

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