未来北极夏季陆面气温变化区域特征及其与北大西洋海面温度的关系

未来变暖背景下北极气候变化特征研究具有重要意义，基于国际耦合模式比较计划第六阶段（Coupled Model Intercomparison Project Phase 6，CMIP6）中对北极气候变化模拟能力较好的模式模拟结果，研究SSP2-4.5情景下21世纪北极2 m气温的时空变化特征及其影响因素。结果表明：（1）极地陆地的欧亚大陆（Eurasia，EA）和北美-格陵兰（Greenland，GL）对全球变暖具有不同的响应。EA在21世纪中叶前变暖趋势显著，之后主要表现为年代际尺度的冷暖振荡；GL则始终保持增暖趋势。EA、GL分区气温均存在年际、年代际（10~20 a）尺度上的波动，GL分区还存在20~40 a的准周期变化。（2）前冬北大西洋涛动正位相会引起次年夏季北大西洋呈南北向“-、+、-”三极型海面温度异常，并通过影响大气环流导致EA分区气温正异常，这种影响主要体现在年代际尺度上。（3）北大西洋多年代际振荡为正异常时，北美至格陵兰位势高度偏高，GL分区增暖，并且这种影响在21世纪70年代后更重要；北太平洋北部的海面温度正异常对GL分区增温也有贡献。

Regional characteristics of the future Arctic summer 2-m air temperature changes and their relationship with the North Atlantic sea surface temperature

The research on the characteristics of Arctic climate change under the background of future warming is of great significance. This research studies the spatio-temporal variability of Arctic 2-m temperature in the 21st century under the SSP2-4.5 scenario based on the climate models with better simulation of Arctic climate change in the Coupled Model Intercomparison Project Phase 6 (CMIP6). The results are as follows. (1) The Eurasia (EA) part and the North America-Greenland (GL) part of the polar continent show different responses to global warming. EA has a significant warming trend before the middle of the 21st century, and then mainly shows the interdecadal oscillations; GL maintains a warming trend. The temperature in the EA part and the GL part fluctuates on interannual and interdecadal (10-20 a) scales, and there is also a quasi-periodic variation of 20-40 a in the GL part. (2) The positive phase of the North Atlantic Oscillation in the previous winter can cause the North Atlantic to present a south-north “-, +, -” tripolar sea surface temperature anomaly (SSTA) in the next summer, and leads to a positive temperature anomaly in the EA part by affecting the atmospheric circulation, and the effect is mainly reflected on the interdecadal scale. (3) When the Atlantic Multidecadal Oscillation is positive, the geopotential height from North America to Greenland is high, the GL part warms, and this effect is more important after the 2070s. The positive SSTA in the north of the North Pacific also contributes to the warming in the GL part.