Preliminary Analysis on Thermal Convective Clouds Generated Locally in Summer of 2019 in Sanjiangyuan Region

With the support of Northwest weather modification project, CMA, observational experiments of local thermal convective clouds were conducted in Sanjiangyuan Region in August and September 2019. Based on on-board X-band dual polarization doppler radar volume-scan data, this paper mainly makes analysis of macroscopic and microscopic characteristics of thermal convective clouds occurred on one day, and makes comparison in point-to-point between satellite observation and radar echoes of thermal convective clouds. The results show that: experimental area had requirements for formation of local thermal convective clouds; movement of thermal convective clouds was from northwest to southeast, whose direction formed a 90°or 150°with topography (clockwise direction) and accorded with wind fields of 500 hPa, and most speed of movement was more than 35 km/h; radar echoes of thermal convective clouds were weak (with 30 to 48 dBz of maximal radar echo reflectivity), which maximal echo top varied from 4 to 5 km; thermal convective clouds were formed by cold cloud mechanism, with less vertical integrated liquid water contents and shorter duration; thermal convective cloud within a typical example was mainly affected by dynamic lifting, and its types of hydrometeor higher than 0°layer consisted of ice crystal, supercooled liquid water and graupel or small hail in developing and mature stages; comparing retrieval Re from FY-4A satellite observation with radar echoes of thermal convective clouds, the two were in good consistency.