Arctic Essay

1595 Words7 Pages
Recent increases in surface temperature in the Arctic have been approximately twice that of the global average over the last 50 years (Chung and Räisänen, 2011). Although the explanations proffered for this amplification of Arctic temperatures is still heavily debated, it is thought that positive Arctic feedback mechanisms in relation to changes in water vapour, cloud formation lapse rate, black body radiation and most notably snow/ice cover (albedo) are considered the primary causes. The recent coincidence of rapid sea ice and snow coverage with extreme weather events in the northern hemisphere has highlighted the possibility of a link between Arctic amplification and mid-latitude weather with research identifying changes in storm tracks,…show more content…
Additionally, due to the nature of emissions causing anthropogenic warming, black carbon deposits on the existing sea ice results in further loss of surface albedo. The declining snowfall observed in parts of the Arctic due to rising temperatures is thought to be exacerbating the positive albedo feedback, (Screen and Simmonds, 2011). Instead of an overall decline in precipitation levels, this decline in snowfall is attributed to the change in form of precipitation from snow to rain; according to Screen et al., (2011), the decrease of surface albedo from this snow loss is comparable in magnitude with the melting of sea ice, as snow is approximately 30% more reflective than ice. Moreover, sea ice plays an important role in insulating the ocean from the colder atmosphere – higher temperatures mean the ice formation in winter is delayed, resulting in a significant flux of heat from the ocean to the atmosphere, thereby enhancing surface warming (Serreze and Barry, 2011). James et al., (2010) argues that, because the maximum Arctic warming is at the surface weakening with elevation in all seasons besides summer, the decline in sea ice and snow cover (which affects surface temperatures) are the primary source of the Arctic Amplification. However, in a recently published paper by Pithan and Mauritsen, (2014) it is suggested that sea ice loss plays a secondary role in Arctic amplification, stating that temperature feedbacks with relation to lapse rate and blackbody radiation are
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