强对流风暴中同质冻结增温的直接探空观测  

Direct observation from sounding of the warming caused by homogeneous freezing in a severe storm

作　　者：徐小红[1] 余兴[1] 戴进[1] 刘贵华[2] 朱延年[1] 岳治国[2] 

机构地区：[1]陕西省气象科学研究所,陕西西安710014 [2]陕西省人工影响天气中心,陕西西安710014

出　　处：《大气科学学报》2011年第4期416-422,共7页Transactions of Atmospheric Sciences

基　　金：国家自然科学基金资助项目(40975087);科技部公益项目(2005DIB3J099);陕西省自然科学基金资助项目(2007D11)

摘　　要：通过两个强对流风暴个例,利用探空资料辅以卫星反演方法,揭示了强对流风暴中同质冻结增温这一事实。探空观测到在强风暴中同质冻结潜热释放造成该层内的空气增温达5℃以上,风暴中强上升气流使云滴没有足够的时间长大,云水向雨水转化和云的晶化会被推到更高的高度,在到达同质冻结高度之前,异质核化过程没有太多的时间消耗大量云水,多数云滴被带到同质冻结高度以上时迅速冻结,造成潜热的集中释放,使周围的空气增温。NOAA卫星观测到的云顶的大量由同质冻结形成的小冰粒子以及过顶现象,进一步证实了同质冻结潜热增温。当探空仪靠近风暴、对流层顶又距同质冻结高度层较近时,同质冻结增温作用有可能被探空仪观测到。By using the radiosonde data and the satellite retrieval and observation,the phenomenon that the homogeneous freezing latent heat warms the air in severe storms is revealed.It was found that the temperature can increase by as much as 5.0 ℃ within that layer in the severe convective storm because of homogeneous freezing.It is mainly because the updrafts are so strong that the cloud drops have no enough time to grow larger and the conversion of cloud drops to hydrometeors and the glaciation of the cloud are delayed to higher heights.Heterogeneous ice nucleation does not have time to deplete much of the cloud water before reaching the homogeneous glaciation level.Thus most cloud drops are carried to the height of homogenous freezing and are instantly frozen into ice crystals,which releases the latent and warm the ambient air.The phenomenon is also verified by the NOAA satellite observation that small ice particles formed by homogenous freezing on the cloud top and overshooting top.The warm effect of homogeneous freezing could be detected by the sounding when it is close to the storm and the tropopause is close to the height of homogeneous freezing.

关 键 词：潜热释放 增温 强对流风暴 探空 卫星反演 

分 类 号：P458.12[天文地球—大气科学及气象学]