太阳光谱辐射强度变化对地球能量平衡的影响分析

目前太阳对地球能量平衡影响的研究大都是以太阳总辐射通量密度作为输入参数的. 本文以美国航空航天局（National Aeronautics and Space Administration，NASA）太阳辐射与气候实验项目的卫星实测数据为基础，对太阳上升相（2010年上半年）和下降相（2007年12月）期间太阳光谱变化对地球能量平衡的影响进行了研究. 结果表明，2010年上半年较强的太阳总辐射通量密度主要是由紫外及红外波段的能量增强引起的，其在200～400nm 和760～4000nm波段内的平均能量分别增加了0.11%和0.05%，而在 400～760nm可见光区的能量却呈减小趋势，平均减小量为0.05%. 通过对MLS2.2全球臭氧日数据进行再分析后发现，相对于2007年12月，2010年上半年平流层臭氧浓度也有所增加，其中在太阳紫外辐射呈现较大增强的2月和3月，其臭氧增量也相对较大，最大值分别出现在33km和40km处，值为0.6mL·m-3和0.62mL·m-3. 因此，可见光区能量减弱与平流层臭氧浓度增加的双重削弱作用致使虽然2010年上半年的太阳总辐射通量密度较大，但是到达对流层顶的太阳辐射却有所减小，最大减小量出现在3月，值为0.15W·m-2. 这一结果说明，太阳活动或总辐射通量密度的增强也有可能对地球对流层系统起到冷却作用. 

Impact of Spectral Solar Irradiance Variations on the Energy Balance of the Earth

The total solar irradiance is usually adopted when studying the solar impact on the energy balance of the Earth at present. However, based on the Solar Radiation and Climate Experiment irradiance record, the impact of solar spectral variations on the global energy balance between December 2007 and the First Half 2010, which were in the descending and ascending solar phase respectively, is studied. The results show that the relatively larger total solar output in the First Half 2010 was mainly caused by the radiation enhancements in ultraviolet and infrared regions, with increments of 0.11% in 200～400nm and 0.05% in 760～4000nm respectively, while the radiation in visible region of 400～760nm decreased by 0.05%. According to the reanalysis of the daily ozone data from MLS Version 2.2, the concentration of stratospheric ozone also increased in the First Half 2010 at the same time. Especially, in February and March whose ultraviolet enhancements are relatively higher than those in other months, the ozone increments are also higher, with maximum of 0.6mL·m-3 and 0.62mL·m-3 respectively at altitudes of 33km and 40km. As a result, the radiation reduction in visible region and concentration increase in stratospheric ozone together contributed to the smaller solar radiation at the tropopause in the First Half 2010 as compared with that in December 2007, with the maximum reduction of 0.15W·m-2 in March 2010. The results mean that the increase in solar activity or total output may also cool the Earth-Troposphere system.