Satellites have been collecting data point on the Greenland shabu tack since 1981 . But since the mid-’90s , scientists have noticed the sheet has become more and more obscure .
The satellites have been measuring the “ albedo ” of the Greenland ice sheet , essentially how much sunlight is reflected back from the surface towards infinite . The process is not viewable with the human optic , but the stage of albedo is detectable through planet instruments . Researchers from Columbia ’s Earth Institute have collected and psychoanalyse the data in a written report recently published in the journalThe Cryosphere .
Their finding country that if the current vogue of darkening continues , part of the sheet will be 10 percentage less brooding by the end of the twenty-first one C than they are today .
So what on the nose is going on ?
The study enounce crock from wildfire in China , Siberia , and North America getting into the ice is no doubt lead . However , using theGlobal Fire Emissions Database , they chance there was no increase in the number of wildfire from the mid - nineties , indicate another culprit was at frolic .
They found that the real driver for the change was rising temperatures . From 1996 forrader , the chalk began absorbing about 2 percent more solar radiation sickness per decennium . This is in line with the findings that the close - surface temperatures in Greenland have been increasing by 0.74 ° C per X .
The snowpack of the sheet undergoes a unvarying mental process of thaw and refreezing throughout the seasons . However , the warmer and bright summer are producing a bigger thaw in the ice . With each of these refreezings , the grains of ice get turgid and larger . The enceinte the grains get , the less meditative a open they have , hence they become drab .
The literal egress with this blackening is the venomous lot it creates . As you ’ll know if you touch the bonnet of a inglorious car on a red-hot day , darker color are less reflective so absorb more light and , significantly , heat . The darker the ice gets , the more vulnerable it is to thawing , so it gets dark-skinned , and the cycle persist in .
" It ’s a complex organization of interaction between the atmosphere and the ice sheet surface . go up temperature are raise more melting , and that melting is reducing albedo , which in bend is increasing melting , " lead author Professor Marco Tedesco , from the Columbia University ’s Lamont - Doherty Earth Observatory and NASA , said ina statement .
" As thawing uphold , the feedback from decline albedo will add up . It ’s a train operate downhill , and the pitcher’s mound is getting steeper , " Tedesco added .
