{"id":7300,"date":"2016-01-13T10:47:16","date_gmt":"2016-01-13T10:47:16","guid":{"rendered":"http:\/\/revoscience.com\/en\/?p=7300"},"modified":"2016-01-13T10:47:16","modified_gmt":"2016-01-13T10:47:16","slug":"clouds-like-blankets-trap-heat-and-melting-the-greenland-ice-sheet","status":"publish","type":"post","link":"https:\/\/www.revoscience.com\/en\/clouds-like-blankets-trap-heat-and-melting-the-greenland-ice-sheet\/","title":{"rendered":"Clouds, like blankets, trap heat and melting the Greenland Ice Sheet"},"content":{"rendered":"
\"1280px-Greenland-ice_sheet_hg-775x528\"<\/a>
A new study shows clouds are playing a larger role in heating the Greenland Ice Sheet than scientists previously believed, raising its temperature by 2 to 3 degrees compared to cloudless skies and accounting for as much as 30 percent of the ice sheet melt. HANNES GROBE.<\/figcaption><\/figure>\n

The Greenland Ice Sheet is the second largest ice sheet in the world and it\u2019s melting rapidly, likely driving almost a third of global\u00a0sea level rise.<\/span><\/p>\n

A new study shows clouds are playing a larger role in that process than scientists previously believed.<\/span><\/p>\n

The study, published in\u00a0Nature Communications<\/span><\/a>\u00a0and led by the\u00a0University of Leuven<\/span><\/a>\u00a0in Belgium, shows that clouds are raising the\u00a0temperature of the Greenland Ice Sheet by 2 to 3 degrees compared to cloudless skies and accounting for as much as 30 percent of the ice sheet melt.\u201cOver the next 80 years, we could be dealing with another foot of sea level rise around the world,\u201d says\u00a0Tristan L\u2019Ecuyer<\/span><\/a>, professor in the\u00a0Department of Atmospheric and Oceanic Sciences<\/span><\/a>\u00a0at the University of Wisconsin\u2013Madison and co-author of the study. \u201cParts of Miami and New York City are less than two feet above sea level; another foot of sea level rise and suddenly you have water in the city.\u201d<\/span><\/p>\n

[pullquote]Researchers already know that while clouds can change the climate, the climate can also change clouds, a phenomenon known as cloud-climate feedback.[\/pullquote]<\/p>\n

Numerous statements in the Nobel Peace Prize-winning 2007 Intergovernmental Panel on Climate Change report address the need to better account for clouds in climate models, L\u2019Ecuyer says. Arctic clouds are no exception, especially since climate models have not kept pace with the rate of melting actually observed on the Greenland Ice Sheet.<\/span><\/p>\n

\u201cWith climate change at the back of our minds, and the disastrous consequences of a global sea level rise, we need to understand these processes to make more reliable projections for the future,\u201d says Kristof Van Tricht, the University of Leuven graduate student who led the study. \u201cClouds are more important for that purpose than we used to think.\u201d<\/span><\/p>\n

But in order to better understand them, the right technology needed to be in place.<\/span><\/p>\n

\u201cWithin the last 10 years, NASA launched two satellites that have just completely changed our view of what clouds look like around the planet,\u201d says L\u2019Ecuyer, who is affiliated with the UW\u2013Madison\u00a0Space Science and Engineering Center<\/span><\/a>, where satellite meteorology was born.\u00a0\u201c<\/span>Once you know what the clouds look like, you know how much sunlight they\u2019re going to reflect and how much heat from Earth\u2019s surface they\u2019re going to keep in.\u201d<\/span><\/p>\n

When it comes to heat, clouds essentially behave in two ways: They either cool the Earth\u2019s surface by reflecting sunlight back into space, or, like a thick blanket, they trap heat at the surface \u2014 the greenhouse effect of clouds. On Greenland, which is covered in bright, light-reflecting snow, clouds primarily act to trap heat.<\/span><\/p>\n

Using the two satellites \u2014 CloudSat and CALIPSO \u2014 L\u2019Ecuyer was able to take \u201cX-ray images\u201d of Greenland\u2019s clouds from space between 2007 and 2010 and determine their structure, how high they were in the atmosphere, their vertical thickness, and their composition (ice or liquid).<\/span><\/p>\n

The Belgian team combined this data with ground-based observations, snow model simulations and climate model data to map the net effect of clouds. They learned that cloud cover prevents the ice that melts in the sunlight of day from refreezing at night.<\/span><\/p>\n

\u201cA snowpack is like a frozen sponge that melts during the day,\u201d says Van Tricht, who spent six weeks in Madison last year working with L\u2019Ecuyer. \u201cAt night, clear skies make a large amount of meltwater in the sponge refreeze. When the sky is overcast, by contrast, the temperature remains too high and only some of the water refreezes. As a result, the sponge is saturated more quickly and excess meltwater drains away.\u201d<\/span><\/p>\n

Researchers already know that while clouds can change the climate, the climate can also change clouds, a phenomenon known as cloud-climate feedback. L\u2019Ecuyer is optimistic that the study \u2014 a good example of how satellites are helping us solve the complicated cloud-climate feedback problem \u2014 will improve future climate models, to help scientists and policymakers across the world adapt to climate change.<\/span><\/p>\n

With a background in physics, L\u2019Ecuyer is driven to study clouds by a desire to better understand how people and society are affected by the natural world. \u201cMany of the countries most susceptible to sea level rise tend to be the poorest; they don\u2019t have the money to deal with it,\u201d he says. \u201cThis is something we have to get right if we want to predict the future.\u201d<\/span><\/p>\n

\n","protected":false},"excerpt":{"rendered":"

The Greenland Ice Sheet is the second largest ice sheet in the world and it\u2019s melting rapidly, likely driving almost a third of global sea level rise.<\/p>\n","protected":false},"author":6,"featured_media":7301,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[15,17],"tags":[],"class_list":["post-7300","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-environment","category-research"],"featured_image_urls":{"full":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/01\/1280px-Greenland-ice_sheet_hg-775x528.jpg",448,305,false],"thumbnail":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/01\/1280px-Greenland-ice_sheet_hg-775x528-150x150.jpg",150,150,true],"medium":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/01\/1280px-Greenland-ice_sheet_hg-775x528-300x204.jpg",300,204,true],"medium_large":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/01\/1280px-Greenland-ice_sheet_hg-775x528.jpg",448,305,false],"large":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/01\/1280px-Greenland-ice_sheet_hg-775x528.jpg",448,305,false],"1536x1536":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/01\/1280px-Greenland-ice_sheet_hg-775x528.jpg",448,305,false],"2048x2048":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/01\/1280px-Greenland-ice_sheet_hg-775x528.jpg",448,305,false],"ultp_layout_landscape_large":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/01\/1280px-Greenland-ice_sheet_hg-775x528.jpg",448,305,false],"ultp_layout_landscape":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/01\/1280px-Greenland-ice_sheet_hg-775x528.jpg",448,305,false],"ultp_layout_portrait":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/01\/1280px-Greenland-ice_sheet_hg-775x528.jpg",448,305,false],"ultp_layout_square":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/01\/1280px-Greenland-ice_sheet_hg-775x528.jpg",448,305,false],"newspaper-x-single-post":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/01\/1280px-Greenland-ice_sheet_hg-775x528.jpg",448,305,false],"newspaper-x-recent-post-big":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/01\/1280px-Greenland-ice_sheet_hg-775x528.jpg",448,305,false],"newspaper-x-recent-post-list-image":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/01\/1280px-Greenland-ice_sheet_hg-775x528.jpg",95,65,false],"web-stories-poster-portrait":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/01\/1280px-Greenland-ice_sheet_hg-775x528.jpg",448,305,false],"web-stories-publisher-logo":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/01\/1280px-Greenland-ice_sheet_hg-775x528.jpg",96,65,false],"web-stories-thumbnail":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2016\/01\/1280px-Greenland-ice_sheet_hg-775x528.jpg",150,102,false]},"author_info":{"info":["Amrita Tuladhar"]},"category_info":"Environment<\/a> Research<\/a>","tag_info":"Research","comment_count":"0","_links":{"self":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/posts\/7300","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/users\/6"}],"replies":[{"embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/comments?post=7300"}],"version-history":[{"count":0,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/posts\/7300\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/media\/7301"}],"wp:attachment":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/media?parent=7300"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/categories?post=7300"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/tags?post=7300"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}