摘要
2011年7月11—13日,黑龙江省西部连续出现3次中尺度强对流天气,伴有短时强降水、冰雹、大风和雷电等天气。利用多种观测资料,对MCS环流、中尺度及物理量特征进行研究,探讨低涡系统下MCS的演变规律。结果表明:地面辐合线和干线是触发强对流天气产生的重要因素。高低空一致的切变线和辐合线促使MCS的发展,MCS向不稳定能量区移动。假相当位温、K指数、沙氏指数和上干下湿的水汽条件及上冷下暖的温度平流等对MCS发生发展有重要指示作用。飑线发生在MCS云团强度梯度大的前边界,该地域是强对流天气的多发地。
Three mecoscale convective systems（MCS） occurred successively in the west of Heilongjiang province on July 11-13,2011, which accompanied short-time heavy precipitation, hail, gale, lightning and thunderstorm and so on. Based on the observational data, the circulation feature of MCS and its physical variables were analyzed in order to discuss the evolution of MCS under the low vortex system. The results indicate that the surface conver- gence line and dry line are key factors in severe convective trigger mechanism. Shear line and convergence line in different altitudes make MCS developing and moving to the areas where there is instability energy. Physical varia- bles such as pseudo-equivalent potential temperature,K index,S/index, water vapor with upper dry and lower wet, temperature advection with upper cold and lower warm flow have important indicative significances for evolution of MCS. Squall line occurs in the front boundary of MCS where cloud cluster has major intensity gradient and short-time severe convection occurs frequently.
出处
《气象与环境学报》
2013年第2期1-5,共5页
Journal of Meteorology and Environment
基金
中国气象局气象关键技术集成与应用项目(GMAGJ2012M17)
国家自然科学基金(411750431)
国家气象局北方预报专家创新团队项目共同资助
关键词
MCS
地面辐合线
低涡
飑线
Mecoscale convective system（MCS）
Surface convergence line
Low vortex
Squall line
