摘要
对主要用FY-2C/D卫星并融合其他观测资料反演的云顶高度与多普勒雷达回波顶高的关系作了初步探讨。通过对20个主要由积层混合云和层状云造成的降水个例总数万个样本的统计分析表明,卫星反演云顶高与SA型号雷达回波顶高存在较好的正相关关系,两者的关系对组合反射率因子的大小不敏感。卫星反演云顶高与小于18 dBz反射率因子对应的回波顶高比与18 dBz回波顶高更接近,这主要是由于FY-2C/D卫星和SA型号雷达探测和反演的原理不同造成,卫星云顶高反映的是积层混合云和层状云顶部云粒子的辐射特性,而回波顶高体现的主要是云中下部较大降水粒子对雷达电磁波的衰减。
A relationship between cloud-top heights retrieved from combination of FY-2C/D geostationary satellite data and other observation data and radar-derived echo-tops is investigated. Tens of thousands of samples from 20 precipitation cases caused by cumuliform stratiform-mixed and stratiform clouds are evalu- ated. It shows that there is remarkably a positive correlation relationship between satellite-derived cloud- top-height and radar echo-top. It is likely that the relationship is hardly dependent upon combined reflec- tivity factor. Cloud-top heights mainly derived by FY-2 are more consistent with echo tops of less than 18 dBz reflectivity factor, compared with those of 18 dBz reflectivity factor because FY-2 satellites and SA- type-radars have different observational and retrieval principles. Satellite-derived cloud-top-height repre- sents radiation characteristics of cloud droplets in the top of cumuliform-stratiform-mixed and stratiform clouds, and meanwhile radar-retrieved echo-top implies ability that larger precipitation particles attenuate electromagnetic waves of radars.
出处
《气象》
CSCD
北大核心
2010年第4期43-50,共8页
Meteorological Monthly
基金
国家"十一五"科技支撑课题"人工增雨信息处理技术研究"(2006BAC12B07)
中国气象局2009年新技术推广项目(CMATG2009MS09)
山东省气象局2006年重点课题"国家级人影业务指导产品的本地化释用"(2006sdqxzl9)共同资助