摘要
利用观测资料和模式计算,讨论了雷暴电活动和环境参量之间的关系。结果指出,地面温湿条件、层结热力不稳定因子、对流有效位能(CAPE)等都不能单一地反映雷暴电活动的强弱。模拟计算指出,云顶高度穿越-20℃温度层时才会产生较强的电活动。云底、-10℃和-20℃层附近空气的热动特性能很好地表征雷暴电活动的强度,且存在一个最佳动能阈值,分别为0.8—0.9,60.0—80.0,20.0J/kg。这3个参量和电荷浓度之间有很好的正相关,但存在上限阈值。另外。
In this paper,observational data and an axisymmetric, time-dependent,numerical cloud model has been applied to study relationship between electrical action and environmental factors in the thunderstorm The results show that the condition of temperature and humidity at ground layer,stratification thermal instable factors,and convective available potential energy(CAPE),and so on can not singly represent intensiver or weaker of electrical action in thunderstorm Simulating calculations show that only when cloud-top height passes through the temperature layer of -20℃, there are intensive electric actions in the cloud The thermal and kinetic forcing of the air around cloud base and temperature layers of -10℃,-20℃ can well exhibit intension of electric actions in the thunderstorm Above three kinetic forcing have optimum threshold value,0 8 0 9,60 0 80 0,20 0J/kg,respectively There are positive relationships between above three factors and electric charge concentration,and have upper limit threshold value The simulated cloud has the tripolar charge structure for seven plateau stratification conditions
出处
《高原气象》
CSCD
北大核心
1996年第4期438-447,共10页
Plateau Meteorology
基金
国家自然科学基金