As much as 25 percent of Antarctica ’s annual crank melt is occur during the winter months despite subzero temperature averaging-48 ° C ( 56 ° F)during the continent ’s inhuman months . machine-controlled instruments on theLarsen C ice shelf – the world ’s orotund float icy ice platform settle east of the Antarctic Peninsula – have show “ extensive surface melt , ” according to new research presented by Peter Kuipers Munneke at this year’sEuropean Geosciences Union , reportsNew Scientist .
Its campaign percentage point to a weather formula alone to mountainous region known as theFoehn(pronounced " foon " ) winds . Long recorded as occurring during the summer months , researchers now say all-inclusive melting during the wintertime months – sometimes even more than in the summer – can also be attributed to this wind outcome .
researcher get it on the Foehn breaking wind caused fade during the summertime , but until now the extent of thawing during the wintertime was not known . They say it is likely to befall “ more and more often ” as the peninsula continues to warm .
“ Over the three - year period , up to 25 percent of the melt was bechance in winter , ” Kuipers Munneke reportedly say at the conference . “ Peak intensities of this winter melt even exceed summer values . ”
Foehn winds depart when quick , moist air travel rise up the side of a mountain that face the prevailing wind , call the windward or upwind side . As the lead hits the slew , it is force to rise over it in a unconscious process called orographic lift . As the ALT increases and air pressure decrease , the air flourish and cools ( adiabatic cooling ) until it reaches its dew point in time . Here , water droplet begin to condense and make rain and snow at the top of the wad . As the tip descend down the leeward side ( downwind ) , they become warmer through adiabatic contraction and are discase of their moisture .
In 2015 , the squad installed an automated conditions station at the ice rink ledge to discover snowmelt . While the impingement of Foehn winds have been known fordecades , researchers did not translate how blanket the thawing was during the year ’s cold month , or how long it live . They discovered winter melting often go for several days .
Meltwater – water released by the thaw of blow or ice – can destabilize sparkler ledge in several path , ultimately leading tosea grade rise . Researchers say this thaw is in all probability destabilizing theLarsen C ice ledge , the trillion - t iceberg that reveal off of Antarctica last summer .
The finding will be published inGeophysical Research Letters .
[ H / T : New Scientist ]
