How Melting of Arctic Sea Ice Affect Global Warming
Arctic Sea Melting Enhancing the Effect of Global Warming in High
Latitudes
The world warmed by about 0.7°C in the 20th century. Every year in this century has been warmer than all but one in the last century (1998). If carbon-dioxide levels were magically to stabilize where they are now (almost 390 parts per million, 40% more than before the industrial revolution) the world would probably warm by a further half a degree or so as the ocean, which is slow to change its temperature, caught up. But CO2 levels continue to rise. All this affect the ice pack in the Arctic. As temperature rises, ice melts. This causes many problems.
A change to the reflectivity on the surface of the earth; which is called the albedo, affects the amount of solar radiation absorbed by the Earth. As Arctic sea ice continues to melt it exposes open water which is less reflective and causes the albedo to decrease. The reduction in albedo allows more light to be absorbed by the ocean. As the ocean water warms, more heat is added to the air creating a positive feedback and driving Arctic temperatures ever higher. The reduction in sea ice is having a significant impact on arctic ecosystems.
The Arctic sea is home to a wide variety of wildlife, including polar bears, arctic foxes, seals, walruses, and whales, fish species such as Arctic cod and char, and sea birds such as guillemots, auks, and eiders.
Geoscientists all agree that the Arctic has been and will continue to be dramatically impacted by global warming and the other way around. A great amount of the surface in the Arctic is underlain by permanently frozen ground called "permafrost". They highest layer experiences seasonal thawing. Through research recent studies have shown that climatic warming my result in a 12 to 15% reduction in the area covered by permafrost and a 15 to 30% increases in the thickness of the active layer. As temperature rises permafrost melts, releasing stored carbon, but just as importantly, methane.
Latitudes
The world warmed by about 0.7°C in the 20th century. Every year in this century has been warmer than all but one in the last century (1998). If carbon-dioxide levels were magically to stabilize where they are now (almost 390 parts per million, 40% more than before the industrial revolution) the world would probably warm by a further half a degree or so as the ocean, which is slow to change its temperature, caught up. But CO2 levels continue to rise. All this affect the ice pack in the Arctic. As temperature rises, ice melts. This causes many problems.
A change to the reflectivity on the surface of the earth; which is called the albedo, affects the amount of solar radiation absorbed by the Earth. As Arctic sea ice continues to melt it exposes open water which is less reflective and causes the albedo to decrease. The reduction in albedo allows more light to be absorbed by the ocean. As the ocean water warms, more heat is added to the air creating a positive feedback and driving Arctic temperatures ever higher. The reduction in sea ice is having a significant impact on arctic ecosystems.
The Arctic sea is home to a wide variety of wildlife, including polar bears, arctic foxes, seals, walruses, and whales, fish species such as Arctic cod and char, and sea birds such as guillemots, auks, and eiders.
Geoscientists all agree that the Arctic has been and will continue to be dramatically impacted by global warming and the other way around. A great amount of the surface in the Arctic is underlain by permanently frozen ground called "permafrost". They highest layer experiences seasonal thawing. Through research recent studies have shown that climatic warming my result in a 12 to 15% reduction in the area covered by permafrost and a 15 to 30% increases in the thickness of the active layer. As temperature rises permafrost melts, releasing stored carbon, but just as importantly, methane.
References: http://archive.greenpeace.org/climate/arctic99/reports/seaice3.html http://www.economist.com/node/17575027/print http://www.economist.com/world/international/displaystory.cfm?story_id=17572735 http://www.uwsp.edu/geo/faculty/ritter/geog101/textbook/earth_system/Future_Geographies_Feedbacks.html