太阳活动与全球气候变化

Solar Variation and Global Climate Change

太阳不断向地球辐射电磁波和粒子,太阳辐射是地球气候系统最主要的能量来源.地球气候系统对太阳活动的响应是一个复杂的过程,包括辐射过程、动力学过程以及微观物理过程等.根据太阳辐射的卫星观测结果和重建结果,例举了古气候、温度、大气环流和云量等方面太阳影响气候的观测证据,论述了太阳影响气候的三种可能机制,即太阳总辐射变化可以影响地表温度,并通过海气耦合改变大气环流;太阳紫外辐射通过调制平流层的温度和风场影响下面的对流层;太阳通过行星际磁场调制银河宇宙线,而银河宇宙线通过电离大气影响云量,进而改变地球的能量收支.

The Sun continually radiates electromagnetic wave and particles to Earth, and the solar radiation is the main energy resource for the Earth＇s climate system. The response of climate system to the solar variation is very complex, including radiative process, dynamic process and inicrophysics process. This paper reviews the measurements from satellites and reconstruction results by other proxies of the solar irradiance variation, enumerates some climate observational evidence in the fields of paleoclimate, temperature, atmospheric circulations and clouds affected by the solar activity. The three main possible mechanisms by which the solar variation may influence the global climate include： the variability of total solar irradiance could change the earth surface temperature, and thus change the atmospheric circulation via the ocean-atmosphere couple; the solar ultra violet radiations modulate the stratospheric temperature and wind field by heating ozone, and the stratosphere response could then affect the lower troposphere by stratosphere troposphere coupling; the solar modulates galactic cosmic ray through interplanetary magnetic field, and galactic cosmic ray may change the cloud cover via ionizing the atmosphere, which could further change the Earth＇s energy budget.