中国不同地区闪电活动和气溶胶的相关性研究

基于10年(2002~2011)卫星观测资料,研究气溶胶浓度(以气溶胶光学厚度AOD代替),地面温度,相对湿度,海拔高度以及其他数据对中国两个不同地区夏季闪电活动的响应。结果表明,不同地区闪电活动主要影响因素不同。对于气溶胶浓度低的地区(AOD_(ave)=0.14),地面温度(偏相关系数为0.745)、海拔高度(偏相关系数为-0.613)可能是影响该区域闪电活动的主要因素;对于气溶胶浓度高的地区(AOD_(ave)=0.60),地面温度(偏相关系数为0.87)、气溶胶浓度(偏相关系数为-0.823)、相对湿度(偏相关系数为0.818)可能是影响该区域闪电活动的主要因素。另外气溶胶浓度低和高的两个地区气溶胶对闪电活动的影响是相反的。对于气溶胶浓度低的地区,闪电密度与AOD,冰粒子光学厚度(IOT)呈明显正相关(R=0.81,0.82),气溶胶可能主要通过微物理过程增加云滴数量,随之冰粒子含量增多,增强雷暴云活动,促进闪电活动的发生;对于气溶胶浓度高的地区,闪电密度与AOD呈明显负相关(R=-0.78),地面气温与AOD呈负相关(R=-0.29),而IOT与闪电密度无相关性(R=0.09),表明气溶胶可能通过辐射效应,使到达地球表面的太阳辐射降低,地面温度降低,雷暴云强度减弱,使冰粒子含量减少,导致闪电活动减弱。

Lightning and aerosol study in different regions of China

The effect of aerosol (represented by AOD), surface temperature and relative humidity, altitude and other parameters on lightning density in two different China regions on summer season of equal area are studied, to investigate the impact of atmospheric parameters on lightning activity. Results showed that different regions have different influencing factors. Region 1 with relative lower of the aerosol concentration, results showed that surface temperature (Rp = 0.745, Rp: partial correlation coefficient) and altitude (Rp = -0.613) may be the two main factors affect the lightning activity. Region 2 with relative higher aerosol concentration, results suggested that surface temperature (Rp = 0.870), aerosol (Rp = -0.823) and relative humidity (Rp = 0.818) may be the three main factors affecting lightning activity. In addition, the effect of aerosol concentration on lightning activity is different. The microphysical effect on lightning activity is obvious in the region 1 with low aerosol concentration. Which is supported by the positive correlation (R = 0.81, 0.82) among lightning density and AOD, ice cloud optical thickness (IOD), and the dependence of IOD on AOD (R = 0.96), IOD and lightning density (R = 0.82). The radiative effect on lightning activity is dominated with high aerosol concentration in the region 2. Which is supported by the negative correlation (R = -0.78) between lightning density and AOD, and the dependence of surface temperature on AOD (R = -0.29).