Imposing glacier enters Lago Argentino, in Patagonia. /
SDG 15 | life of terrestrial ecosystems
Even complying with the Paris Agreement, half of these great icy masses will melt by the end of the century
“Worse Than 2003: Swiss Glaciers Are Melting More Than Ever”. This is the forceful alert of the Swiss Academy of Sciences that launched at the end of last year. According to official data, the Central European country lost 6% of the volume of ice from its high Pyrenean peaks. An evil that is not isolated, but, rather, pandemic.
These large icy masses are melting “at a rate never seen before,” warns the Swiss Academy of Sciences itself and that the American Association for the Advancement of Science (AAAS) has set a date: 2100. “The Current temperature projections for the end of the century would cause widespread melting in mid-latitudes,” reveals the research published this Thursday.
Glacier melt rates have not stopped increasing in recent decades. Only in Switzerland, according to Swiss data, the frozen mass in the country has fallen by 35% since 2001. «In the best of cases, and that means complying with the Paris Agreements, half of the planet’s glaciers will be lost in 2100,” says the AAAS text. “And half of these will do it much sooner.”
However, the forecast of the 1.5ºC global average temperature agreed at COP21 in the French capital “will not be fulfilled if this path is followed,” warn scientists led by David Rounce, professor at Carnegie Mellon University in USA. “Recent climate pledges from COP26 project average temperatures to rise by as much as 2.7°C over the next century,” the AAAS researchers comment. “This will cause the complete deglaciation of Central Europe, Western Canada, the United States and New Zealand,” they add. Although “higher losses are expected with higher scenarios.”
Rising sea levels
Global warming is gradually melting the historic high mountain glaciers and also cracking their increasingly thin surfaces. A weakness that has manifested itself in recent months with the detachment of ice blocks that have even caused deaths, as happened last summer in the Dolomites in the Italian Alps.
This disappearance also puts the water resources of billions of people at risk: “approximately 1,900 million,” says the AAAS investigation. “The projected losses will alter the availability of annual and seasonal runoff,” they highlight.
An impact that will not only be reflected in the people who live near these glaciers, but as it runs along the slopes of the mountains or on the Antarctic coasts it will raise the sea level.
Globally, glaciers are expected to lose between 26%, under a scenario of 1.5ºC average temperature, and 41%, if they reach 4ºC, of their mass by 2011 in relation to 2015. This loss would imply, American scientists say, an increase in the average sea level between 90 and 99 millimeters in the best of cases, reaching 1.25 or 1.45 meters at the end of the century in the most extreme projections.
Water, mostly fresh, that will reach seas and oceans, especially from Alaska: “It is the largest contributor to the global increase between 2015 and 2100,” reports the AAAS. “It will reach its maximum contribution between 2030 and 2060 with an increase of 0.33 mm and 0.44 mm,” they add. Greenland, the Antarctic and sub-Antarctic, Canada’s arctic north and south are next on the list of contributions.
Although most of these disappearances involve the melting of glaciers less than one square kilometer in area “has a great impact on local hydrology, tourism and cultural values,” says Rounce in the text of the research. “More ambitious climate commitments to preserve glaciers are urgently needed.”
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