Sos glaciers, for the Marmolada the fate seems already marked


The fate of the Marmolada There are not many hopes for the Marmolada. According to the scenario outlined by the researchers of the Cnr-Ismar, of the Universities' of Trieste, Genoa and Aberystwith and of Arpa Veneto, "even if the temperature remained as it is, its destiny appears marked". Between 2004 and 2015 it suffered a reduction in volume of 30% and in area of ​​22%. If it was once a unique glacial mass, it is now fragmented and divided into various units, where at different points underlying rocky masses emerge, the researchers note. If the reduction rate continues as in the past decade, between 25-30 years the glacier will have practically disappeared.

World glaciers in danger By the end of the century it will be essential to contain the global temperature increase within 1.5 degrees. If you were to exceed 2 degrees of increase, the ice across the world will disappear, outside the Himalayas and the Poles. Added to this is the loss of snow that would damage the water supply. To say it is the report "Cryosphere 1.5 degrees", presented in Madrid where the Cop25 is underway by a group of 40 researchers who launch an appeal to governments.

The 1.5 ° limit of global temperature increase compared to the pre-industrial one is defined as "a guardrail" for the planet. There is a much greater risk of irreversible and massive increase in sea level at 2 ° (12-20 meters or more in the long term), with consequences for fishing in the polar oceans due to acidification.

20,000 years ago the melting of the Tropic glaciers However, the melting of glaciers is not new to our planet. A study by the University of Dartmouth, published in the journal Sciences Advances, has in fact found that the glaciers that were found in South America and East Africa, in the area that today corresponds to the Tropics, had begun to melt about 20,000 years ago, that is sooner than previously thought. The hypothesis is that this early melting may have been triggered by the increase in temperatures at the poles, which in turn would have reduced the cycle of atmospheric and oceanic circulation, slowing the movement of heat out of the Tropics.

According to the researchers, the glaciers of tropical Africa and South America would reach their maximum extent 29,000-21,000 years ago, and then begin to melt. The withdrawal would therefore have occurred before the increase in carbon dioxide occurred 18,200 years ago. This would show that tropical temperatures increased all over the planet and that warming could have been caused by a reduction in temperature differences between the polar and tropical regions. Unlike, however, 20,000 years ago, in this case the main defendant for melting glaciers is man.

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