The Arctic energy budget, sea ice area, and the atmospheric circulation

Abstract

Arctic amplification and changes in Arctic sea ice has led to questions regarding the role of the Arctic in mid-latitude climate. All studies concerning the factors and the impacts suggest that changes in the Arctic system occur in association with altered energy fluxes. Therefore, this study explores Arctic energy fluxes in detail concentrating on their temporal and regional characteristics using the Climate Forecast System Reanalysis (CFSR) dataset. To understand how energy flux variations affect the Arctic climate, interactions among energy flux variables, Arctic sea ice, and prominent atmospheric teleconnections are investigated. These interactions are analyzed from two spatial perspectives: the entire Arctic and the sub-Arctic regions. Results from the entire Arctic showed that the annual cycle and the spatial distribution of energy fluxes follow the seasonal cycle, latitudinal variation, and surface conditions. No significant long-term trends are found for the energy flux variables; however, the accumulated total energy tendency suggests a prolonged period with energy flux surplus from 1995-2006. Significant correlations were found among energy fluxes, sea ice, and the NAO suggesting that sea ice variations are connected with changes in atmospheric circulation through the surface energy flux (F sfc ) directly or indirectly through the atmospheric energy transport (TEDIV). Maps of the spatial correlations show stronger relationships between these variables in unique regions. Hence, studying these energy fluxes and the relationship from a regional perspective is essential. Examination of coherent regions shows that the annual cycle and the time series of the Arctic sub-regions are similar to the average for the entire Arctic following the solar cycle and without long-term linear trends. Only the annual cycle for TEDIV show differences among regions and do not resemble the average Arctic pattern. Additionally, a hypothetical pathway with two time-scales of variation is suggested. These two levels of influence complement each other and provide a comprehensive picture of the interactions among Arctic energy fluxes, sea ice, and atmospheric circulation. Further, the analysis suggests that sea ice variation is an important factor in modulating Arctic energy fluxes, and the Kara region plays a critical role in linking sea ice variability and atmospheric circulation.