Atmospheric moisture transport: the bridge between ocean evaporation and Arctic ice melting

Abstract

Abstract. Changes in the atmospheric moisture transport have been proposed as a vehicle for interpreting some of the most significant changes in the Arctic region. The increasing moisture over the Arctic during the last decades is not strongly associated with the evaporation that takes place within the Arctic area itself, despite the fact that the sea ice cover is decreasing. Such an increment is consistent and is more dependent on the transport of moisture from the extratropical regions to the Arctic that has increased in recent decades and is expected to increase within a warming climate. This increase could be due either to changes in circulation patterns which have altered the moisture sources, or to changes in the intensity of the moisture sources because of enhanced evaporation, or a combination of these two mechanisms. In this short communication we focus on the more objective assessment of the strong link between ocean evaporation trends and Arctic Sea ice melting. We will critically analyse several recent results suggesting links between moisture transport and the extent of sea ice in the Arctic, this being one of the most distinct indicators of continuous climate change both in the Arctic and on a global scale. To do this we will use a sophisticated Lagrangian approach to develop a more robust framework on some of these previous disconnecting results, using new information and insights. Results reached in this study stress the connection between two climate change indicators, namely an increase in evaporation over source regions (mainly the Mediterranean Sea, the North Atlantic Ocean and the North Pacific Ocean in the paths of the global western boundary currents and their extensions) and Arctic ice melting precursors.

Atmospheric River Impacts on Greenland Ice Sheet Surface Mass Balance

“…Recent studies have found evidence of an increasing trend in poleward moisture transport toward the GrIS (Mattingly et al, —hereafter M16) and the Arctic basin (Alexeev et al, ; Boisvert & Stroeve, ; Cao et al, ; Gong et al, ; Lee et al, ; Park et al, ; Woods & Caballero, ), in accordance with predictions of enhanced moisture transport to the Arctic in a warming climate (Gimeno et al, ; Graversen & Burtu, ; Lavers et al, ; Yoshimori et al, ). In light of these observed and projected trends, and recent case studies suggesting that ARs may play a significant role in determining the evolution of GrIS SMB, an examination of AR trends and impacts on GrIS SMB across a much larger sample of moisture transport events is needed.…”

Moisture transport into the Arctic: Source‐receptor relationships and the roles of atmospheric circulation and evaporation

“…From a general point of view, variations in moisture transport can be due to (a) changes in general circulation patterns, (b) increases or reductions in moisture supply from particular sources caused by changes in evaporation, or (c) a combination of these two effects [ Gimeno et al ., , ]. Several previous studies have shown the influence of circulation patterns and evaporation [e.g., Aagaard and Greisman , ; Oort , ; Hanssen‐Bauer and Førland , ; Rogers et al ., ; White et al ., ; Gimeno et al ., ] on the Arctic atmospheric hydrological system. Most studies related to the transport of moisture into the Arctic region make use of three different methodologies: analytical and box models, physical water vapor tracers (isotopes), and numerical water vapor tracers (WVT).…”

“…For this purpose, the present study makes use of the Lagrangian method developed by James [2004, 2005] to identify and analyze the major sources of moisture for the whole Arctic domain. This approach was successfully applied to the characterization of sources of moisture in regions close to the Arctic or within it, such as Iceland [Nieto et al, 2007], Norway [Stohl et al, 2008], and Eurasia [Wegmann et al, 2015;Gimeno et al, 2015].…”

Characterization of Moisture Sources for Austral Seas and Relationship with Sea Ice Concentration

“…Among the multiple atmospheric and oceanic drivers controlling the sea ice variability, little attention has been paid to the moisture transport from the extratropics to the Southern Ocean [23,31,32], a mechanism proposed to have an important role in the Arctic atmospheric hydrological system e.g., [33,34], with implications for the Arctic Sea ice extension. Indeed, atmospheric moisture transport is a primary source of water in polar regions, and, according to [23], through the cloud radiative forcing, it directly or indirectly affects the snow, sea ice, and ice sheet.…”