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On Tuesday, December 8, the National Oceanic and Atmospheric Administration (NOAA, the US government’s climate agency) released a new report on conditions in the Arctic, indicating a marked change that is causing it to be even more warm. Ice and snow are less present in the region, which is increasingly characterized by the presence of rain and large areas of open sea where huge ice shelves used to be concentrated.
For 15 years, NOAA experts have published the Arctic Report Card every year, which contains data and analysis collected in one of the areas of the planet most exposed to the phenomena of climate change, largely caused by human activities. More than 130 researchers from 15 countries contributed to this year’s report. The results of their work were published online and presented at the annual conference of the American Geophysical Union (AGU).
Climate change is a global phenomenon, but in some areas the increase in temperature is occurring faster than in others. The Arctic is warming about twice the rate of much of the rest of the planet.
The increase in the average temperature in the Arctic region brings with it several secondary effects: rising sea levels and modifying ocean currents, to name just two phenomena that affect life in entire ecosystems and cause numerous imbalances for millions of living species. Changes in the Arctic are also one of the causes of the increasingly extreme weather events that occur each year, according to the latest research and scientific models.
The amount of ice that covers part of the Arctic Ocean varies with the seasons, and the ice sheet decreases during the summer months. This year was more pronounced than usual and was the second most evident since the extent of sea ice was detected with satellite studies. Above-average ice loss has also affected the Greenland ice sheet and major glaciers in Alaska.
The higher-than-average summer temperature resulted in a fairly extensive melting of the permafrost, the layer of soil that is perpetually frozen under normal conditions. The phenomenon has been observed for several years and with growing concern about its effects on flora and fauna, not to mention the increased risk of releasing large amounts of carbon dioxide and other greenhouse gases into the atmosphere, which are released after permafrost melting. .
In addition, in the Eurasian Basin the amount of snow reached a record low last June, despite the fact that the snowfall had been abundant: the anomalous heat accelerated the thaw and evaporation. The resulting less available water has led to a prolonged period of drought, with large-scale fires affecting several thousand square kilometers. Particularly in Siberia, the fires destroyed numerous coniferous forests, releasing around 30 percent more carbon dioxide into the atmosphere than the previous year.
In the Arctic Circle, the average ground temperature recorded between October 2019 and September this year was 1.9 ° C higher than the average calculated between 1981 and 2010. It was also the second highest ever detected and indicated in the records of the last century.
The change in temperature is having a tangible effect on the amount of ice in the Arctic. The largest reduction was recorded in 2007 and has never returned to previous levels since then, despite fluctuations recorded annually. Under these conditions, the possibility of retreating seems remote, if not impossible, as reported in a study published last September by two American researchers on changes in the amount of sea ice.
About thirty years ago, ice at least 4 years old alone made up about a third of the Arctic ice sheet at the end of winter. According to the latest NOAA findings, this old ice now makes up less than 5 percent of the ice. Newly formed ice is less compact and is usually thinner, so it is much more exposed to melting due to higher temperatures. This affects the total volume of ice available, as has been found with measurements in recent years, which have revealed new all-time lows.
The general conditions of the Arctic are considered worrisome also in light of the general trend of global warming and the poor results obtained so far to combat it, despite the promises of many governments in recent years. Rick Thoman, one of the report’s authors, gave a rather alarming description of the new paper: “It describes an Arctic region that continues to warm, less icy, and biologically modified in ways that were hardly imaginable a generation ago. . Virtually everything in the Arctic, from ice to snow to human activities, is changing at such a speed that there is no reason to think that thirty years from now there will still be anything comparable to what it is today.
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