What happens in the Arctic does not stay in the Arctic, it affects the climate of the entire planet. And what is happening this October is that the Arctic Ocean is too hot to regain its ice sheet at the usual rate.
So, as the graph above shows, the Arctic ice sheet has never been this small at this time of year. The year 2012 (dotted line) holds the record with the least ice since data is available, however then the ice re-formed with the arrival of autumn, as usual.
On the other hand, this year (blue line), with the high temperatures that Siberia and other areas of the Arctic have been registering, the water is too hot and the ice is not being able to form at the usual speed (in gray, the usual average is shown since nineteen eighty one).
The season also broke records with a thaw higher than that of 2012 in between March and June and some days in July.
You can consult the interactive graph with the sea ice surface of the Snow & Ice National Data Center at this link.
In addition, temperatures continue to be high this month throughout the Arctic region, making the thickness of the remaining ice sheet much less than usual as shown in the graph by Dr. Zachary E. Labe, a researcher at the University of Colorado.
Consulted by euronews, Labe explains that most of this anomaly “the worst formation of sea ice in satellite observations” is due to the very high temperatures that the Siberia region has been experiencing since the beginning of the year, a heat wave that has beat records.
He expects the ice to form again and, although he remembers that in addition to climate change there is significant interannual variability and Siberia could have more ice than the average next year, this episode is consistent with observations of the effects of global warming on the Arctic.
Samantha Burgess, Deputy Director of the Climate Change Service of the European Copernicus network explains that the exceptional heat of the Siberian Arctic “makes sea surface temperatures warmer than average, which makes it more difficult for ice to melt. reform “. He believes it is early to assess the effects on the global of the season but warns of probable “impacts for the marine food web with fewer nutrients available and for ice-dependent species, such as polar bears and walruses.”
Belgian glaciologist Xavier Fettweis comments that this situation shows that the state of the Arctic cannot be measured only with respect to the frozen surface “you also have to take into account the heat content in open water, which is the hidden face of the iceberg. , and that has surely broken a record this year, but it is [un dato] less known. “He believes that this season, taking this factor into account, could be worse than in the fateful 2012 and fears that this situation will worsen next year, leaving a weakened ice sheet that will melt faster in the 2021 season.
He also points out that with more evaporation, rainfall increases, although not necessarily at the North Pole.
The loss of ice, especially the oldest and thickest, causes a vicious cycle, because ice has a harder time forming in winter and melts faster in summer. At the moment the ice volume estimated by the Danish Meteorological Institute (graph above) is low, but does not reach the record set in 2019.
The other two large ice sheets on the planet, Greenland and Antarctica, remain stable, within approximately the average values.
What happens in the Arctic does not stay in the Arctic, it affects the global climate
If scientists and experts insist so much on monitoring the dramatic changes that are taking place in the Arctic, it is because the poles have a fundamental regulatory role for the climate balance of the entire planet.
The Arctic is experiencing the effects of climate change twice as fast as the rest of the globe in what is known as Arctic amplification. And these changes then have an impact on the climate of the entire planet. Added to this is the accelerated melting of glaciers or permafrost, the frozen soil that covers peaks and steppes in both hemispheres, which also releases greenhouse gases such as methane.
The exact effects of melting are not yet precisely known, however there are some immediate consequences:
The poles act like a refrigerator. When they have less ice, they absorb heat instead of reflecting it. This also makes ice formation difficult, as Professor Fettweis pointed out and as we are observing this year.Sea level rise. It is one of the most obvious effects of the melting of the cryosphere.Pertubation of the life of the communities and the ecosystem. It is the most immediate and obvious effect. The region’s populations have had to adapt to the lack of ice for years. Also the fauna, which also has fewer resources to adapt.More precipitation and more damaging storms. In addition to generating more evaporation and therefore more water available for precipitation, some scientists believe that disturbances in the Arctic cause changes in the jet stream that dictates the climate of the northern hemisphere.Changes in marine circulation. Melting is capable of altering ocean currents, which are also closely linked to global climate.More heat waves. Scientists believe that imbalances in oceanic and atmospheric currents can cause, in addition to stronger winter episodes, more intense heat waves in summer.Changes in salinity. The lack of ice alters the chemical balance of the oceans and can lead to fewer nutrients, or an excess of certain animals or algae.
The MOSAIC mission, the largest Arctic exploration ever carried out, has just returned from the region and one of its main objectives is precisely to collect data on the advance of climate change in the fragile Arctic balance.