In this paper, some distinctive features of the vertical profile of precipitable liquid water content (LWC) with considerable respect to rain rates (R) and radar reflectivity (Z) obtained in a tropical location are pr...In this paper, some distinctive features of the vertical profile of precipitable liquid water content (LWC) with considerable respect to rain rates (R) and radar reflectivity (Z) obtained in a tropical location are presented. Assessment of LWC allows applications in the specific area of flight icing severity, aviation safety as well as signals traversing through the atmosphere. The parameters were typically measured using vertically-pointing Micro Rain Radar (MRR) over a period of 2 years (2011-2012) at Akure, a tropical location of Nigeria. The radar scanned at every 10 seconds and integrated over one minute samples to reduce event logging error associated with the instrument. The vertical profile of the LWC typically reveals a prominent seasonal variation. However, majority of the LWC profiles has low LWC, less than 0.1 gm?3 while the maximum observed LWC is about 3.18 gm?3. A strong like hood relation was observed between the melting layer height and the LWC, with the LWC reaches peak at the considerable height of about 4160 m which coincides precisely with the freezing height level (rain height of ~4520 m) of the study location. Good correlation was also observed between the LWC and R in most of the heights considered. The results obtained will assist system engineers to assess the level of absorption, reflection and attenuation of electromagnetic signals as a result of precipitable LWC along the transmitting paths. The novelty of the present work is in the area of linking LWC and Z as against usual relation between Z and R.展开更多
利用Micaps资料、多普勒雷达资料及德清国家观测站(58454)的实时观测数据等,对2018年7月26日发生在德清县的一次暴雨、冰雹、大风等强对流天气过程的环流形势背景场、中尺度特征、物理量场等气象资料进行分析,结果表明:此次突发性强对...利用Micaps资料、多普勒雷达资料及德清国家观测站(58454)的实时观测数据等,对2018年7月26日发生在德清县的一次暴雨、冰雹、大风等强对流天气过程的环流形势背景场、中尺度特征、物理量场等气象资料进行分析,结果表明:此次突发性强对流天气主要受蒙古冷涡渗透的冷空气与稳定维持的副热带高压环流的共同作用,强烈的边界层辐合线是触发机制;冰雹发生前后各项热力和动力指标发生明显变化,典型的上干下湿的大气结构有利于产生降雹;孤立的对流单体合并处产生冰雹,强中心可达71 d BZ,中气旋和VIL极大值区域对应冰雹落区。此次强对流天气的分析,为今后提高强对流天气的预报预警时效和准确率提供参考。展开更多
文摘In this paper, some distinctive features of the vertical profile of precipitable liquid water content (LWC) with considerable respect to rain rates (R) and radar reflectivity (Z) obtained in a tropical location are presented. Assessment of LWC allows applications in the specific area of flight icing severity, aviation safety as well as signals traversing through the atmosphere. The parameters were typically measured using vertically-pointing Micro Rain Radar (MRR) over a period of 2 years (2011-2012) at Akure, a tropical location of Nigeria. The radar scanned at every 10 seconds and integrated over one minute samples to reduce event logging error associated with the instrument. The vertical profile of the LWC typically reveals a prominent seasonal variation. However, majority of the LWC profiles has low LWC, less than 0.1 gm?3 while the maximum observed LWC is about 3.18 gm?3. A strong like hood relation was observed between the melting layer height and the LWC, with the LWC reaches peak at the considerable height of about 4160 m which coincides precisely with the freezing height level (rain height of ~4520 m) of the study location. Good correlation was also observed between the LWC and R in most of the heights considered. The results obtained will assist system engineers to assess the level of absorption, reflection and attenuation of electromagnetic signals as a result of precipitable LWC along the transmitting paths. The novelty of the present work is in the area of linking LWC and Z as against usual relation between Z and R.
文摘利用Micaps资料、多普勒雷达资料及德清国家观测站(58454)的实时观测数据等,对2018年7月26日发生在德清县的一次暴雨、冰雹、大风等强对流天气过程的环流形势背景场、中尺度特征、物理量场等气象资料进行分析,结果表明:此次突发性强对流天气主要受蒙古冷涡渗透的冷空气与稳定维持的副热带高压环流的共同作用,强烈的边界层辐合线是触发机制;冰雹发生前后各项热力和动力指标发生明显变化,典型的上干下湿的大气结构有利于产生降雹;孤立的对流单体合并处产生冰雹,强中心可达71 d BZ,中气旋和VIL极大值区域对应冰雹落区。此次强对流天气的分析,为今后提高强对流天气的预报预警时效和准确率提供参考。
