摘要:
利用气象观测资料、NCEP再分析资料、GDAS资料，结合HYSPLIT模式分析2018年1月3—4日鄂北地区大暴雪的异常环流形势和水汽输送特征。结果表明：1）100 hPa极涡向亚洲东北部分裂，极锋急流位置偏南，500 hPa乌山的阻塞形势和偏强偏东的东亚大槽，有利于将强冷空气向我国中东部输送；700 hPa强盛的西南急流配合850 hPa偏东风辐合，提供有利的动力、水汽；地面冷高压势力偏强，从东路南下并不断补充，有利于降雪天气长时间的维持。2）整层水汽通量高值舌从华南沿海伸至长江沿线，鄂北地区水汽输送强度、水汽辐合偏强；4条水汽输送路径分别是650 hPa干冷空气在黄海转向从东北路输送水汽，水汽贡献率排第二；650～700 hPa气团将孟加拉湾的水汽输送至暴雪区，水汽贡献率排第一；500 hPa干冷空气自偏西方向过来，水汽贡献率最少；近地层暖湿气团将南海水汽自偏南路径输送至暴雪区，水汽贡献率排第三。与一般降雪过程比，增加了偏南的输送路径，且水汽贡献最多和次多路径的气团水汽含量更高。
Abstract:
Using meteorological observation data, NCEP data and GDAS data, combined with HYSPLIT model, the atmospheric circulation and water vapor transport characteristics of heavy snowstorm in northern Hubei from 3 to 4 January 2018 were analyzed.The results show that:1) The 100 hPa polar eddy splits to the northeast of Asia, the position of the polar front jet is southly, there is Ural Blocking situation at 500 hPa and the East Asian trough is eastern and stronger, it’s conducive to conveying strong cold air to the central and eastern part of China; the 700 hPa southwest jet and 850 hPa cold pad provide favourable conditions for dynamic condition, water vapor condition; the surface cold anticyclone is stronger, come from east and constantly replenishing, it’s advantageous to keeping snowfall for a long time.2) The high value of whole layer vapor transportation fluxes extends from south China to the Yangtze River region.Water vapor transport intensity and water vapor convergence are stronger than perennial in northern Hubei.The four water vapor transport routes are 650 hPa dry and cold air in the Yellow Sea to transport water vapor from northeast, with the second contribution rate of water vapor.Water vapor from the Bay of Bengal is transported to snowstorm area by 650-700 hPa air, with the first contribution rate of water vapor.500 hPa dry and cold air comes from the west, and the contribution rate of water vapor is the least.Near-surface warm and wet air conveys South China Sea vapor from the south to the snowstorm area, with the third contribution rate of water vapor.Compared with the normal snowfall, the transport path to the south is increased, and the water vapor with the first contribution and second contribution is higher.
百度学术
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