基于CALIPSO的长三角地区云光学特性特征分析

Vertical Optical Characteristics of Clouds in the Yangtze River Delta Region Based on CALIPSO

利用CALIPSO卫星提供的激光雷达数据分析了长三角地区云光学特性特征,可知,长三角地区主要云类型为碎积云、卷云、透光高积云、蔽光高积云和层积云,云平均消光系数在0.2~0.4之间,色比值范围在0.02~1.9之间,退偏比分布范围为0~0.9之间,液相云粒子形状更偏向于球型。对云光学参数随季节变化的分析表明,与春夏季相比,秋季10 km以上的云消光能力更强,秋冬季节5 km以下的云色比值更大,但与其他季节相比,夏季对流活动活跃,8 km以下的云粒子退偏比和色比值分布更加均匀。

Using lidar data provided by the CALIPSO satellite,clouds’optical characteristics in the Yangtze River Delta are analysed.It is known that the main cloud types in the Yangtze River Delta are cumulus,cirrus,transparent altocumulus,obscured altocumulus and stratocumulus.The average extinction coefficient of clouds is between 0.2 and0.4,the colour ratio is between 0.02 and 1.9,and the distribution range of the depolarisation ratio is 0-0.9 In the ball type.The analysis of the seasonal variation of cloud optical parameters shows that compared with spring and summer,the cloud extinction capacity of more than 10 km in autumn is more robust,and the cloud colour ratio below 5 km in autumn and winter is larger.However,the convective activity is active in summer,and the depolarisation ratio and colour ratio distribution of cloud particles below 8 km is more uniform than other seasons.