Editing IPCC:AR6/WGI/Chapter-Atlas (section)

===== Atlas.11.2.1.1 Key Features of the Regional Climate =====

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The Arctic region comprises the Arctic Ocean (ARO), Russian Arctic (RAR), Greenland and Iceland (GIC), and other surrounding land areas in Europe (NEU) and North America (NEN, NWN) (Figure Atlas.29). The region is one of the coldest and driest regions on Earth and plays a key role influencing global and regional climates and the hydrological cycle. A number of physical processes contribute to amplified Arctic temperature variations as compared to the global temperature, in particular thermodynamic changes that include the increase in surface absorption of solar radiation due to surface albedo feedbacks related with sea ice, ice, and snow cover retreat as well as poleward energy transports, water-vapour-radiation and cloud-radiation feedbacks ( [[#Screen--2010|Screen and Simmonds, 2010]] ; [[#Serreze--2011|Serreze and Barry, 2011]] ; [[#Pithan--2014|Pithan and Mauritsen, 2014]] ; [[#Bintanja--2016|Bintanja and Krikken, 2016]] ; [[#Graversen--2016|Graversen and Burtu, 2016]] ; [[#Franzke--2017|Franzke et al., 2017]] ; [[#Stuecker--2018|Stuecker et al., 2018]] ). Precipitation in the Arctic is dominated by snowfall, with rainfall present mostly during the summer period. Arctic climate is influenced by the North Atlantic Oscillation (NAO), the leading mode of atmospheric variability in the North Atlantic basin with a northward extension into the Arctic affecting temperature, precipitation and sea ice over the region, with ENSO and Atlantic Multi-decadal Variability (AMV) also affecting parts of the region (Annex IV). Further, the Greenland Ice Sheet contribution to sea level results from the imbalance between mass gain by net snow accumulation and mass loss by meltwater runoff and ice discharge into the ocean ( [[#IMBIE%20team--2020|IMBIE team, 2020]] ), highlighting that the ice sheet is a major contributor to sea level changes.

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