“It’s easy to focus on that year-to-year variability,” says Bridget Seegers, an oceanographer at NASA. “But it’s important to look at the trend: The last eight years were the eight warmest on record.”
To calculate global temperatures, both agencies pull data from weather stations around the world, as well as measurements from ships and floats at sea. Other groups such as Berkeley Earth, a non-profit research organization, do the same with their slightly different methodology. But the analyzes are nearly identical in their conclusions. As you can see in the graph below, which compares results from Berkeley Earth, NOAA, NASA and two other groups in Europe, global mean temperatures may be lower in 2021 than in 2020, but it may still be is growing.
One reason for the cooler temperatures in 2021 was La Nia, a band of cold water in the Pacific. It is the product of strong trade winds that scour the ocean, pushing the upper layer of water toward Asia, bringing deeper, cooler water to the surface to fill the void. This in turn affects the environment, for example jet stream change Above and Leading the United States more storms in the Atlantic. The ocean itself cools things by absorbing heat from the atmosphere.
The COVID-19 pandemic may have an added effect, but not in the way you might imagine. As the world shuts down in 2020, less emissions went into the sky, including aerosols that typically reflect some of the Sun’s energy back into space. Gavin Schmidt, director of NASA’s Goddard Institute for Space Studies, announced the findings during a Thursday press conference, saying, “If you take them away, you clean the air, it would have a mild warming effect on the climate.” Is.” But as economic activity picks up in 2021, so did aerosol pollution, which again contributed to that cooling effect. The drop in temperatures for 2021 “could probably be due to the resumption of aerosol-generating activity in the atmosphere,” Schmidt said.
(The decline in pandemic-based carbon dioxide production did not have a cooling effect. Human civilization produced so much of the planet-warming gas each year, and it remained in the atmosphere for so long, that it didn’t even register as a pandemic.) a blip.)
Today’s findings are even more worrying as 2021 managed to address these cooling effects and Still The sixth highest temperature matching. And while global temperatures were cooler in 2021 than the year before, last year 1.8 billion people lived in places where their warmest ever recorded. report good Released today by Berkeley Earth. This includes Asian countries such as China and North and South Korea, African countries such as Nigeria and Liberia, and places in the Middle East such as Saudi Arabia and Qatar. “We talk a lot about the global average temperature, but no one lives within the global average,” says Zeke Hausfather, a research scientist at Berkeley Earth. “Indeed most of the world, two-thirds of it, is ocean, and no one lives in the ocean – or at least very few people. And land areas are warming much faster, on average, than the rest of the world ”
Since the land is warming so fast, increasingly frequent and intense heat waves are tyrannizing people living in different parts of the world. In western Canada and the US Pacific Northwest last summer, absurd temperatures over 120 degrees Fahrenheit killed hundreds of people, According to Hausfather, a heat wave in Portland, Oregon, would have been effectively impossible without climate change, an event that occurs once every 150,000 years. “By the end of the century, at the rate that things are heating up right now, this is going to be a 1-in-10, 1-in-5-year event,” Hausfather says. “They are what we call the ‘return period’ for these extreme heat events that shorten as the world gets warmer.”
This Berkeley Earth map above gives a better idea of what we’re dealing with. La Nia affected that part of the cold blue coast along the coast of South America. But the bright red areas suggest that North Africa, the Middle East and China were roasting. And watch the red splatter over the arctic, which is warming four times faster as the rest of the planet. This is due to several factors, including the fact that as ice melts, it exposes the deeper ground beneath, which absorbs more of the Sun’s energy, raising local temperatures and accelerating melting. Is. The frozen ground known as permafrost is now melting so rapidly that it is piercing the Arctic landscape, spewing more greenhouse gases into it.
Land around the world is warming faster than the ocean, as you can see in the graph above. But a warmer ocean also raises sea levels, as the water expands when it warms and the warm water melts the sea ice. (The graph below from NASA shows the decline of sea ice in the Arctic.) In Antarctica, Thwaites’ “Doomsday Glacier” is declining rapidly, partly because warm water is chewing on its belly. If it melts, and collapses between nearby glaciers, they together can add 10 feet to sea level.