平流层地球工程将导致东亚冬季风显著增强

[发布日期: 2023-03-30 浏览量 2372]

【中文介绍】

      平流层气溶胶注入地球工程（以下简称平流层地球工程）是通过人为向平流层注射有散射效应的气溶胶粒子或其前体物（如SO2）的方式来增加行星反照率，减少到达地表的太阳辐射，进而实现全球降温的太阳辐射干预地球工程方法。随着全球变暖日趋严峻，该项技术在气候变化领域备受关注。虽然相关领域的学者已基于模拟资料分析了平流层地球工程的可能全球气候影响，但聚焦东亚地区的研究相对较少。

      为此，课题组使用CMIP6多模式试验数据，研究了热带平流层地球工程对东亚冬季风的影响和机制。研究发现，21世纪末期东亚冬季风将在平流层地球工程强迫下显著增强，具体表现为西伯利亚高压增强、阿留申低压增强南移、东亚沿岸对流层低层北风增强和东亚大槽加深。其中，赤道中太平洋的强降温和异常下沉运动引起了向极传输的罗斯贝波波列，这是造成东亚冬季风增强的主要原因；同时，西伯利亚高压区的对流层中层负涡度平流和辐射冷却也对冬季风的增强有一定贡献。

【英文介绍】

The stratospheric aerosol injection geoengineering (stratospheric geoengineering, SG) is a solar radiation modification method to increases planetary albedo by injecting aerosol particles or their precursors (such as SO2) into the stratosphere, and then cool the Earth. So far, global warming has become increasingly severe. The SG technology has attracted much attention in the climate change field. Although scientists have discussed the possible global climate impacts of SG based on simulations, the research focusing on the East Asian climate is still few.

In this study, we investigated the impact and mechanism of the tropical SG on the East Asian winter monsoon (EAWM) by using CMIP6 multi-model experiment. Our results show that the SG significantly strengthens the EAWM system in the late 21st century, which is obviously seen from the strengthened Siberian high, the intensified and southward shifted Aleutian low, the enhanced low-level northerly winds along the coast of East Asia and the deepened East Asian trough. Further analysis indicates that the SG-induced strong cooling and anomalous descending motion in the central-equatorial Pacific excites a poleward-propagating Rossby wave, strengthening the EAWM circulation. Meanwhile, the negative vorticity advection in the middle troposphere and the radiative cooling over the Siberian high region caused by SG also intensify the EAWM.

图1 2080–2099年G6sulfur试验中冬季（a）气温、（b）降水、（c）海平面气压、（d）850 hPa风场、（e）500 hPa相对涡度和（f）300 hPa纬向风气候态相对于SSP5-8.5变化的模式集合平均结果。斜线和阴影区域表示至少5/6的单一模式同模式集合平均符号一致。

【引用格式】

Liu ZC, Lang XM, Miao JP, Jiang DB (2023). Impact of stratospheric aerosol injection on the East Asian winter monsoon. Geophysical Research Letters, 50, e2022GL102109.