Amplified wintertime Barents Sea warming linked to intensified Barents oscillation
Amplified wintertime Barents Sea warming linked to intensified Barents oscillation
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DOI：
10.1088/1748-9326/ac5bb3
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发表时间：
2022-03
影响因子：
6.7
通讯作者：
Ziyi Cai;Qinglong You;Hans W. Chen;Ruonan Zhang;Deliang L. Chen;Jinlei Chen;Shi-chang Kang;J. Cohen
中科院分区：
文献类型：
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作者：
Ziyi Cai;Qinglong You;Hans W. Chen;Ruonan Zhang;Deliang L. Chen;Jinlei Chen;Shi-chang Kang;J. Cohen
近几十年来，巴伦支海在冬季变暖的速度是北极其他地区的两倍多，但这种放大变暖背后的确切原因仍不清楚。在这项研究中，我们量化了冬季巴伦支海变暖（BSW，近地表气温），平均线性趋势为1.74 °C十年-1，并在2003年左右基于使用1979-2019年ERA 5再分析数据集的表面能量收支分析的年代际变化。我们的分析表明，在冬季近地面气温的年代际变化是由增强晴空向下长波辐射（CDLW）与总柱水汽增加。此外，它被发现，在北大西洋地区的大气变率模式被称为巴伦支振荡（BO）强烈的贡献，在2003年的逐步跳跃的BSW。2003年以来，北大西洋和巴伦支海以南地区的异常高压为BO的加强和正位相，促使格陵兰岛南部沿着挪威海和欧亚大陆向巴伦支海输送两支水汽和热量。这增强了巴伦支海上空的水汽辐合，通过增强CDLW导致BSW。我们的研究结果突出了与BO相关的大气环流，作为冬季BSW的一个新兴驱动因素，通过增强北大西洋上空的纬向大气热量和水分输送。
In recent decades, the Barents Sea has warmed more than twice as fast as the rest of the Arctic in winter, but the exact causes behind this amplified warming remain unclear. In this study, we quantify the wintertime Barents Sea warming (BSW, for near-surface air temperature) with an average linear trend of 1.74 °C decade−1 and an interdecadal change around 2003 based on a surface energy budget analysis using the ERA5 reanalysis dataset from 1979–2019. Our analysis suggests that the interdecadal change in the wintertime near-surface air temperature is dominated by enhanced clear-sky downward longwave radiation (CDLW) associated with increased total column water vapor. Furthermore, it is found that a mode of atmospheric variability over the North Atlantic region known as the Barents oscillation (BO) strongly contributed to the BSW with a stepwise jump in 2003. Since 2003, the BO turned into a strengthened and positive phase, characteristic of anomalous high pressure over the North Atlantic and South of the Barents Sea, which promoted two branches of heat and moisture transport from southern Greenland along the Norwegian Sea and from the Eurasian continent to the Barents Sea. This enhanced the water vapor convergence over the Barents Sea, resulting in BSW through enhanced CDLW. Our results highlight the atmospheric circulation related to the BO as an emerging driver of the wintertime BSW through enhanced meridional atmospheric heat and moisture transport over the North Atlantic Ocean.