摘要
利用一维雷暴云起电放电模式,初步模拟了STEPS(夏季雷暴降水与闪电研究计划)一次雷暴个例的一些基本电学特性。模拟的电荷结构为:雷暴云上部为正电荷,下部为负电荷,即符合典型雷暴云的偶极性电场分布特征,放电层电场随时间变化规律呈锯齿状分布。在此基础上,对云底高度和温度垂直递减率进行了敏感性试验,研究这两种因子对雷暴电过程的影响。结果表明:当云底高度降低时,放电高度升高,闪电频数增加,首次放电时间随之提前,即放电过程变强。温度垂直递减率增大,闪电频数降低,首次放电时间随之延后,正负电荷的分布范围减小。
One-dimensional thunderstorm electrification model was used to simulate the basic elec- trific characteristics of a thunderstorm case in STEPS. The simulated charge sturcture is the classic dipolar structure ： positive charge in the upper part of thunderstorm while negative in the lower part ; the evolution law of electrical field in discharge layer becomes sawtooth; the vertical distribution of the positive and negative electrical field locations conforms to the typical electrical field distribution of thuderstorm. Fur- thermore, a sensitivity test is carried out to analyze the impact of cloud base height and temperature lapse rate on electrical process of thunderstorm. Results show that when the cloud base height decreases, the discharging location goes up and lightning becomes frequent, the first lightning appears sooner. The first lightning has to defer but lightning frequency decreases with the temperature lapse rate increasing, re- spectively.
出处
《气象科学》
北大核心
2015年第2期126-132,共7页
Journal of the Meteorological Sciences
基金
公益性行业(气象)科研专项(GYHY201106044)
江苏省高校优势学科建设工程资助项目(PAPD)
江苏省普通高校研究生科研创新计划项目(CXZZ13_0507)
关键词
雷暴
云底高度
温度垂直递减率
数值模拟
Thunderstorm
Cloud base height
Temperature lapse rate
Numerical simulation
作者简介
通信作者（Corresponding author）：银燕（YIN Yan）．yinyan@nuist．edu．cn
