Theoretical Studies of Cold Air Damming

南阿巴拉契亚山脉的东坡向西阻挡了持续、稳定和浅的冷空气圆顶，这是晚秋和冬季常见的中尺度特征。由于东部与之相邻的大西洋水域温暖得多，这种冷空气阻塞是区分降雨预报与更危险的冰冻降水形式（雪、雨夹雪、冰雨和雨）预报的主要因素。当它存在并持续存在时，它也有利于沿海冬季风暴的快速发生和增强。不幸的是，观测、分析和预报系统的分辨率不足，以及缺乏理论认识，导致对这些事件的预报很差。类似的现象也发生在科罗拉多州的Front Range，影响了丹佛-柯林斯堡城市走廊的大雪分布，并且在世界各地的其他山坡上也有记录。徐的目标是提高我们对冷空气阻塞的理解，并为其后果的诊断和短期预测制定定量标准。他是一位杰出的年轻研究者，被公认为是考虑具体天气预报问题的理论水动力学领军人物之一。

Persistent, stable and shallow domes of cold air dammed to the west by the eastern slopes of the southern Appalachian mountains are a common mesoscale feature in the late fall and winter. Because of the neighboring, much warmer Atlantic waters to the east, this cold air damming is a major factor in distinguishing forecasts of rain from those of the more dangerous frozen precipitation forms (snow, sleet, freezing drizzle and rain). When it is present and persistent it also favors the rapid genesis and intensification of coastal winter storms. Unfortunately, inadequate resolution of the observational, analysis and forecast systems, as well as a lack of theoretical understanding, have caused poor forecasts of these events. Similar phenomena also occur along Colorado's Front Range, affecting the distribution of heavy snow in the Denver-Fort Collins urban corridor, and have been documented on other mountain slopes around the world. Xu's goal is to improve our understanding of cold air damming and to develop quantitative criteria for the diagnosis and short term forecasting of its consequences. He is an outstanding younger investigator and is recognized as one of the leading group of theoretical hydrodynamicists considering concrete weather forecasting problems.