宇路,傅云飞. 2017. 基于星载微波雷达和激光雷达探测的夏季云顶高度及云量差异分析[J]. 气象学报, 75(6):955-965, doi:10.11676/qxxb2017.070
基于星载微波雷达和激光雷达探测的夏季云顶高度及云量差异分析
Analysis of cloud-top height and cloud amount difference between spaceborne microwave radar and laser radar detection in boreal summer
投稿时间:2017-01-17  修订日期:2017-06-27
DOI:10.11676/qxxb2017.070
中文关键词:  云顶高度  云量  CPR  CALIOP
英文关键词:Cloud top height  Cloud amount  CPR  CALIOP
基金项目:国家自然科学基金项目(41230419、91337213、41675041)、公益行业专项(GYHY201306077)。
作者单位E-mail
宇路 中国科学技术大学地球与空间科学学院, 合肥, 230026  
傅云飞 中国科学技术大学地球与空间科学学院, 合肥, 230026 fyf@ustc.edu.cn 
摘要点击次数: 1451
全文下载次数: 1382
中文摘要:
      云是天气与气候变化的重要影响因子,准确估量云顶高度和云量对分析云特性、降水及强天气预报、估算云辐射强迫等都具有重要意义。利用2006-2010年6-8月CloudSat卫星搭载的微波云廓线雷达(CPR,简称微波雷达)和CALIPSO卫星搭载的云-气溶胶偏振激光雷达(CALIOP,简称激光雷达)的探测资料,分析了全球云顶高度及云量的空间分布特征。结果表明,热带地区微波雷达探测云顶高度平均比激光雷达低约4 km,但均超过12 km;副热带洋面云顶高度在4 km以下,且两部雷达探测的云顶高度差异存在地域性。微波雷达对薄云、云砧及云顶高度低于2.5 km的低云存在漏判,对厚云的云顶高度偏低估;微波雷达探测的全球总云量均值为51.1%,比激光雷达少23.3%;两者给出的云量分布也存在显著的海-陆差异,其中洋面云量差异更大,如微波雷达测出局部洋面云量为80%,而激光雷达的探测结果却超过90%。由于激光雷达发射波长短,对云顶微小粒子比较敏感,而微波雷达波长较长,对相对较小粒子的探测存在局限性。因此,激光雷达对云顶高度的探测优于微波雷达。此结果不仅加强了对激光雷达和微波雷达探测原理的认识,而且进一步理解了云的气候特征。
英文摘要:
      Cloud is a critical factor for weather and climate change. Accurate estimation of the cloud top height and cloud amounts are very important for cloud characteristics analysis, precipitation forecast, and cloud radiative forcing study. Based on the measurements of the Cloud Profile Radar (CPR) and Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) carried by CloudSat and CALIPSO respectively, spatial distributions of global cloud top height and cloud amounts are investigated for the summer from June to August over the period of 2006-2010. The results show that the averaged cloud top height detected by CPR is 12 km against 16 km measured by CALIOP in the tropics. The cloud top heights detected by both CPR and CALIOP are mostly below 4 km in the subtropical ocean with large regional differences between measurements of CPR and CALIOP. Compared with the cloud top heights detected by the CALIOP, the CPR misdetected thin clouds, cloud anvils and clouds below 2.5 km, and underestimated the cloud top heights of thick clouds. The global mean cloud amount detected by CPR is 51.1%, which is 23.3% less than that by CALIOP. The results also show a significant sea-land difference in the distribution of cloud amounts with the largest difference occurring in the ocean. 80% of global clouds are found above the oceans based on CPR while more than 90% are over the oceans based CALIOP. Because of the short wavelength of CALIOP, it is sensitive to tiny particles, whereas CPR cannot detect relatively small particles. Therefore, CALIOP is better than CPR in detecting cloud top. Results of the present study not only enhance our understanding of detection principles of CPR and CALIOP, but also provide more information about the climatic characteristics of clouds.
HTML   查看全文   查看/发表评论  下载PDF阅读器
分享按钮