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Home / Science / Arctic climate change produces unprecedented heat, fire and melting ice

Arctic climate change produces unprecedented heat, fire and melting ice



This week, for example, with blazes swirling across Siberia, smoke hit the skies all the way in portions of Alaska. In Svalbard, a Norwegian archipelago in the Arctic that has seen staggering warming rates in recent years, all-time temperature records have been set, turning glaciers that have already fallen to pieces, lined with so much molten turquoise water that it was visible from space.

The Svalbard archipelago is one of the fastest warming places on Earth, with sea ice and glaciers falling. In Longyearbyen, Svalbard, the most northern resident dwelling, with more than 1

,000 residents, temperatures rose to 71.1 degrees (21.7 Celsius) on July 25, setting a record high for this locality. Longyearbyen had a four-day series that exceeded 68 degrees (20 Celsius), a feat that had only been seen once before, in 1979.

At the same time, the low temperature overnight dropped below 62.2 degrees (16.8 Celsius) at 25, setting a record for the warmest low temperature.

The average high and low temperatures at this time of year in Longyearbyen are 49 (9.4 Celsius) and 41 degrees (5 Celsius).

The ice cap in Svalbard has the highest surface mass loss of any Arctic ice sheet so far this summer and has hit a record for ice surface and melting of the Arctic. ice on July 25, when temperatures rose, said Xavier Fettweis, a scientist at the University of Liège, Belgium.

Arctic-spread fire emissions set records

While the extreme temperatures of Siberia – including a record probable Arctic temperature of all time of 100.4 degrees (38 Celsius) recorded in June in Verkhoyansk, located above the Arctic Circle – received the most attention, it is the missing fires that have many effects. beyond this region. These fires have continued on their relentless pace since June.

Every day, the smoke, which contains the greenhouse gases that warm the planet, was poured into the air, while on earth the flames stabilized the permafrost by burning protective vegetation to the ground. above the permanently frozen soil. This also adds to climate change, releasing carbon and methane.

On many days during July, milk hair of smoke thick enough to obscure the ground was visible on satellite imagery extending across a range covering most of the 48 Southern states. The most severe fires were accompanied by peeled feathers, known as pyrocumulonimbus clouds, or pyroCbs.

Arctic fire-fighting carbon emissions, driven primarily by Siberian fires, reached a record high in July, according to the Copernicus Atmosphere Monitoring Service, a European Union science agency based in Leve, England. Such data draw back 18 years, with an increase in Arctic fire emissions seen during that period.

Between July 1 and July 23, the estimated total carbon emissions in July from fires in the Siberian Arctic amount to 100 metric megatons of carbon dioxide, said Mark Parrington, a senior scientist. of the Copernicus Atmosphere Monitoring Service, via email. Parrington said this is on top of the 59 metric megatons of carbon dioxide emanating from the Arctic Circle fires in June.

“The large gathering of fires well in the Siberian Arctic Circle has been burning at high intensity (higher than the highest daily total calculated for the region in 2019) for several days and looking to continue,” Parrington said on -Last week, predictions that turned out to be true.

On Wednesday, Twitter, Parrington said: “July 2020 was ignited by previously unseen Arctic fires” in data collected by the Copernicus Atmosphere Monitoring Service. Estimated satellite firefighting carbon emissions, Parrington said, are moving at twice the amount seen during the previous record Arctic fire season, which was last year. .

Smoke from these fires, including ash and carbon monoxide, spread across the Chukchi Sea to Alaska.

Siberia has experienced record heat for the calendar year so far. Siberian fires and, particularly prolonged heat were already directly linked to man-made climate change.

In a quick analysis, the researchers found that long-term heat from June to June in northern Siberia occurred at least 600 times more likely than man-made climate change. This led them to conclude that such an event would be almost impossible in the absence of global warming.

In addition, other parts of the Arctic are starting from the effects related to climate change, along with temporary temporary factors.

Meanwhile, extreme temperatures in the Scandinavian Arctic and Siberia have also spread to northern Canada. On July 25, a temperature of 71.4 degrees was recorded in Eureka, Nunavut, located in the Canadian Arctic at 80 degrees north latitude. According to Mika Rantanen, a researcher at the Finnish Meteorological Institute, that may be the record high temperature so far in the north.

In an example of how extreme weather events may interact with long-term climate change-related trends, a strong low-pressure zone arose earlier this week on the Beaufort Sea, in the north. of Alaska, potentially melting the sea with ice. The low level is reminiscent of a severe storm that engulfed the sea ice cover during the 2012 summer melting season. That storm helped accelerate ice loss, leading to an all-time snow cap, a record.

Despite being of similar intensity, the recent storm is unlikely to have the same effects on the trajectory of the melting season, say sea ice experts. While noting that the range of sea ice lies in low-lying territory, the region collided with a region filled with the thickest ice in the Arctic. Most of the ice loss this summer came on the Arctic side of the Eurasian, including northern Siberia, where the North Sea Route probably opened in the Its first record date, a full month ahead of average.

“The key is really the storm time and the thickness of the ice that is there,” said Julienne Stroeve, a senior scientist at the National Ice and Ice Data Center (NSIDC) in Boulder, Colo.

There is a chance that the storm could speed up the melting of the ice, but it depends on a number of factors.

“Because storms tend to cause ice divergence, if the storm pushes some of the ice into the Beaufort [Sea] towards him [the] Stering Bering then is likely to melt, as ocean temperatures there are up to 5 Celsius warmer than average, ”Stroeve said.

Walt Meier, a colleague of Stroeve’s NSIDC, noted that the 2012 storm hit later in the melting season and in a region where ice cover was already distributed and scattered (low concentration). So there were a lot of opportunities for the storm to catch waves and really decide the ice.This year, the ice in that region is, at least at the moment, looking more formidable.It is more compact and so this year’s storm may not have the same impact as in 2012. We’ll see. ”

The bottom line

Almost uniformly, scientists studying Arctic warming highlight how changes are occurring rapidly in the vast region. A study published Wednesday in Nature Climate Change supports this impression, showing that “major portions” of the region have been warming at a rate of 1.8 degrees (1 Celsius) every decade for 40 years, constituting an “event f ‘a blow to climate change’. when considered in the light of paleoclimate records of sudden episodes in the past.

The study found that even the harshest climate model scenarios tend to underestimate the recent pace and extent of climate change in the Arctic. Co-author Martin Stendel, a research scientist at the Danish Meteorological Institute, wrote via Twitter that “[a]Sudden dditional changes can only be avoided after a low emission scenario. ”




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