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towards the second half of the century. If these goals are met, at least part of the
remaining snow and glaciers could be preserved on the planet.
Snow decrease
"Majestic is the white mountain" highlights the lyrics of our national anthem.
Although this is still true after a good winter snowfall, unfortunately, in recent
decades, our white mountains have been darkening, not only in the Chilean
Andes but worldwide, affecting the availability of snow and water from melting
snow and ice. The main reason is global climate warming.
Seasonal snow, which is deposited during the rainfall period, coincides with the
winter season in our country (except in the extreme north), which melts and
sublimates (direct transfer from the solid to vapor state) during spring and
summer. White clean snow has been strongly affected in our country by
warming and drought.
As a result of warming, the zero-isotherm altitude has been rising as a result of
temperature increase, so now it rains in areas where it used to snow. This effect
is well known to skiers, particularly at low-level ski resorts, in virtually all
mountain
ranges,
including the
Australian Alps,
the
European
Alps,
the
Appalachian Mountains in North America, and also in the Andes. In central
Chile, for example, skiing in the Gran Bajada of Farellones stopped decades
ago, and the skiing days at Lagunillas and Chapa Verde are increasingly scarce.
Studies indicate that in central Chile, the zero degrees C isotherm has risen 127
meters in the period 1958-2018 (Barria et al. 2019), and by the end of the
century, there could be an additional rise of 440 meters in most unfavorable
scenarios of greenhouse gas emissions, with atmospheric temperatures that
would exceed the current ones by about 4˚C (Carrasco et al., 2005).
Additionally, the mega-drought that has affected a large part of Chile since 2010
has resulted in a drastic decrease in precipitation, including reduced snow
accumulation in the mountains. Although the year 2023 we have had a very
welcome respite, with rainfall close to normal conditions in central Chile, it does
not, unfortunately, mean that this dry period has ended, with most likely dry
conditions prevailing in the future in the area. Global warming, along with the
mega-drought, is forming the "perfect storm"; in other words, a reduction of
storms originating from the Pacific Ocean, which impact the western Andes
mountains, depositing its moisture as snowfall. Results show that from the north