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How Is Global Warming Affecting the Arctic? The Arctic is being watched closely by global warming specialists. It’s a particularly sensitive region and it is being profoundly affected by the changing climate – many scientists view what is happening now as a sign of things to come for the rest of the world, it has been said to be an early warning system for the entire planet. More Greenhouse Gases Released From Permafrost The permanently frozen ground underneath the Arctic Tundra, called permafrost, supports pipelines, buildings and roads. The temperature increase is causing this permafrost to thaw. ‘Drunken forests’ where trees fall over as the ground underneath them thaws have become more common. However, there is also more impact than just these visible ones as the permafrost thaws. Carbon and methane have been locked in the permafrost and beneath the cold Arctic waters (in subsea permafrost) for millions of years. These greenhouse gases are increasingly being released into the atmosphere, causing more warming. This in turn releases more greenhouse gases and in a vicious cycle. Accelerated Warming From Changing Albedo Albedo is the extent to which a surface can reflect sunlight. Lost sea ice exposes dark, open water, dramatically shifting the ocean surface from highly reflective white snow that reflects about 90% of the sun’s energy to open water which absorbs around 94%. As the open water of the ocean absorbs more heat, it causes more sea ice to disappear, and a feedback process begins. Over the last two centuries, the world’s global mean temperature has increased by 0.6°C and this trend goes beyond the natural climate variability. In the Arctic, average temperatures have risen almost twice as fast as in the rest of the world. Melting Land Ice Melting sea ice does not affect sea levels, but melting of land ice does. The water from shrinking glaciers and ice sheets is the major contributor to the rise in global sea-level. Freshwater is being added to the world’s oceans, affecting salinity, an abiotic factor in ecosystems. Arctic ice is getting thinner, melting and rupturing. The Ward Hunt Ice Shelf was around for 3000 years and in 2000 it began to crack. By 2002 it had split all the way through and it is now breaking into pieces. When this happened, the