Possible impacts of a future grand solar minimum on climate: Stratospheric and global circulation changes.
Possible impacts of a future grand solar minimum on climate: Stratospheric and global circulation changes.
复制标题
DOI：
10.1002/2014jd022022
复制
发表时间：
2015-09-27
期刊：
影响因子：
--
通讯作者：
Osprey SM
中科院分区：
文献类型：
--
作者：
Maycock AC;Ineson S;Gray LJ;Scaife AA;Anstey JA;Lockwood M;Butchart N;Hardiman SC;Mitchell DM;Osprey SM
有人认为太阳在世纪可能会演变成一个活动较低的时期。这项研究使用一个综合的全球气候模式来研究极端的“蒙德极小期”太阳极小期开始的潜在气候影响。在21世纪下半叶，该情景假设与参考代表性浓度路径8.5实验相比，总太阳辐照度下降0.12%。太阳辐照度的减少使平流层顶（101 hPa）全年和全球平均冷却1.2K。对全球平均近地表温度的影响很小（约-0.1 K），但在平流层动力活跃的季节，区域气候发生了较大的变化。在北方的冬季，平流层西风急流会减弱1.3 ~ 4 m s−1，最大的变化发生在1 ~ 2月。这伴随着阿留申低压在地面的加深和北方欧洲和北太平洋上空阻塞的增加。在南半球春季，南半球中纬度涡动驱动急流也有向赤道方向的移动。在冬季和春季出现放大的区域响应表明，自上而下的路径对太阳气候耦合的贡献;这是使用一个实验来测试的，在该实验中，紫外线（200-320 nm）辐射减少，隔离其他变化。结果表明，太阳活动在21世纪世纪的大幅下降可能对平流层和区域地面气候产生重要影响。未来太阳活动的下降不会抵消预计的全球变暖未来太阳活动的下降可能在冬季产生更大的区域影响自上而下的机制有助于北方半球的区域响应
It has been suggested that the Sun may evolve into a period of lower activity over the 21st century. This study examines the potential climate impacts of the onset of an extreme “Maunder Minimum‐like” grand solar minimum using a comprehensive global climate model. Over the second half of the 21st century, the scenario assumes a decrease in total solar irradiance of 0.12% compared to a reference Representative Concentration Pathway 8.5 experiment. The decrease in solar irradiance cools the stratopause (∼1 hPa) in the annual and global mean by 1.2 K. The impact on global mean near‐surface temperature is small (∼−0.1 K), but larger changes in regional climate occur during the stratospheric dynamically active seasons. In Northern Hemisphere wintertime, there is a weakening of the stratospheric westerly jet by up to ∼3–4 m s−1, with the largest changes occurring in January–February. This is accompanied by a deepening of the Aleutian Low at the surface and an increase in blocking over Northern Europe and the North Pacific. There is also an equatorward shift in the Southern Hemisphere midlatitude eddy‐driven jet in austral spring. The occurrence of an amplified regional response during winter and spring suggests a contribution from a top‐down pathway for solar‐climate coupling; this is tested using an experiment in which ultraviolet (200–320 nm) radiation is decreased in isolation of other changes. The results show that a large decline in solar activity over the 21st century could have important impacts on the stratosphere and regional surface climate. A future decline in solar activity would not offset projected global warming A future decline in solar activity could have larger regional effects in winter Top‐down mechanism contributes to Northern Hemisphere regional response