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Abstract
Rapid changes in atmospheric circulation variability over the North Atlantic region and the extent of surface melting across the Greenland ice sheet (GrIS) have been observed during recent decades. In this thesis, a historical climatology of extreme Greenland blocking episodes, associated with unusually strong and persistent synoptic-scale ridges, from 19582013 is examined within the context of anomalous anticyclonic circulation patterns over Greenland during recent years. The role of other atmospheric and oceanic features within the North Atlantic climate system, including extratropical cyclone activity and sea surface temperatures, on the evolution of extreme Greenland blocking episodes and GrIS melting is also examined. Contributions from adiabatic and diabatic sources of heating are quantified in order to determine processes associated with blocking anticyclones and precursor cyclones that can enhance GrIS melting. The long-term increase in Greenland blocking, coupled with additional factors, suggests that GrIS melting may continue to accelerate into the future.