作　　者： ; ; ; ; (魏强）; (韩志刚）;

机构地区： 北京大学物理学院

出　　处： 《气象学报》 2011年第3期521-527,共7页

摘　　要： 飞机探测可直接获取云的微观结构特征量,但只是一些线段;卫星遥感资料可大范围监测云环境,但不是直接获得云参量,需要反演。因而开展云的飞机观测结果与卫星资料的对比分析是必要的。对1999月6月4日华北平原上一次层积云过程两个架次的飞机微物理探测资料进行了详细分析,并将飞机盘旋上升和下降取得的5次云参数垂直探测结果作为辐射传输模式SBDART2.4的输入,采取正演的方式与GMS5/VISSR、NOAA15/AVHRR反射通道的资料进行了对比分析。飞机探测显示层积云云厚约1000 m,云粒子浓度最大值425 cm-3,含水量最大值0.2 g/m3。第1架次云粒子浓度、含水量、有效半径的平均值为225±75 cm-3、0.08±0.03 g/m3、7.2±1.6μm,第2架次云粒子浓度、含水量、有效半径的平均值为196±73 cm-3、0.04±0.02 g/m3、4.9±1.4μm。按500 m垂直分层后,云粒子有效半径平均值为6.1±1.7μm,主体云层(1000—1500 m)柱含水量平均值为29.5±17.5 g/m2。敏感性试验表明当有云存在时,云的光学厚度是影响可见光通道反照率的主要因子,利用飞机探测云参数计算的卫星观测反照率与实测值进行的对比分析表明,两者相对偏差为7%,无系统性偏差,说明利用飞机探测资料计算云辐射特征的可信性;同国际上同类观测对比分析表明:中国利用粒子测量系统的谱分布资料计算云的含水量结果是合理的。 The cloud microphysical parameters can be obtained directly by aircraft equipped with the PMS probes, but the measurements made by the in situ probes on aircraft are limited along the flight track. On the other hand, satellite is able to monitor the cloud environment of wide area, but the cloud parameters cannot be obtained directly with inversion needed. The comparisons between aircraft in situ measurements and satellite data are necessary. The cloud microphysical parameters including cloud droplet number concentration, liquid water content and effective radius from the aircraft PMS measurements of 2 flights in Huabei Plain are analyzed in detail. The cloud microphysieal parameters from the vertical observation of 5 ascending and descending legs were used in the SBDART （Santa Bar- bara DISORT Atmospheric Radiative Transfer） to simulate and compared with the data from the spectral channels of the GMSS/VISSR and the NOAA15/AVHRR. And then a comparison between the simulation and the satellite reflective channel measurements was com- pleted. The in situ measurements show that the depth of stratocumulus cloud is about 1000 m, the maximum cloud droplet concentra- tion is 425 cm-3 , and the maximum liquid water content is 0.2 g/m3. During the first flight, the average values of cloud droplet concentration, liquid water content, and effective radius are 225 ± 75 cm-3 , 0.08 ±0. 03 g/m3 and 7.2 ± 1.6μm, respectively. During the second flight, the average values of cloud droplet concentration, liquid water content, and effective radius are 196±73 cm-3 , 0.04± 0.02 g/m3 and 4. 9 ±1.4 μm, respectively. Based on the calculation of the average value at the vertical interval of 500 m, the average cloud effective radius is 6. 1± 1.7μm, and the average stratocumulus cloud liquid water content （the cloud layer extends from 1000 to 1500 m） is typically 29.5 ± 17.5 g/m2. The sensitive analyses indicate that the visible channel reflectance is highly determined by the optical depth in the presence of cloud. In situ

关 键 词： 飞机探测 云微物理参数 辐射特征 对比分析

领　　域： [天文地球]