气候变暖背景下降水持续性与相态变化的研究综述

持续性降水和固态降水（或近地面气温为0℃左右的降水）都能导致洪涝和低温雨雪冰冻等灾害性的极端事件，对人民群众生命和财产安全以及社会经济发展也会造成严重危害。目前中外围绕降水量、极端降水事件变化等已开展了大量研究，但在降水持续性和相态变化的特征及其影响机理方面的研究仍显不足。因此，围绕降水持续性和相态变化的相关研究，对近20余年来取得的一些重要研究进展进行回顾。研究指出，在气候变暖背景下降水持续性和相态变化的特征在全球范围内表现出了区域上的不一致性。有关降水持续性变化方面，中国南方地区持续性降水过程及其产生的降水量呈现增多趋势，但北方地区呈现减少的趋势，而西南地区长持续性降水呈下降趋势。至于降水相态变化方面，中国南方地区持续性雨雪冰冻事件在气候变暖背景下总体呈减少趋势。这些变化除了与气候变暖有关外，可能还与大气遥相关模态、低频振荡及ENSO事件等引起的大气环流异常有关。今后应该更多开展气候变暖背景下降水持续性和相态变化的特征、可能机理以及其与气候变暖的可能联系方面的研究，以期通过相关研究深入理解中国降水持续性与相态变化的规律、成因及其与旱涝、低温雨雪灾害等的联系，进一步加深对气候变暖背景下中国天气、气候的影响及其机理的认识。 

A review on changes in precipitation persistence and phase under the background of global warming

Persistent precipitation and precipitation in solid forms (or near 0℃ precipitation) always result in disastrous flooding, snow and extreme freezing events, imposing severe impacts on people's lives, property and socio-economic development. Significant progresses have been made in understanding changes in total precipitation and precipitation extremes in China. However, there still exist some gaps in understanding climate changes in precipitation persistence and phase. This paper has reviewed recent progresses and major conclusions with a focus on the above two aspects. Major results are as follows. The trends of changes in precipitation persistence and phase are inconsistent over different regions under the global warming background. In China, persistent precipitation tends to be more frequent and intense over South China but becomes less frequent over North China. Long-duration precipitation in Southwest China tends to be shortened. Accordingly, persistent freezing events over South China display a decreasing trend. The reason for these changes is possible associated with atmospheric circulation anomalies induced by teleconnections low-frequency oscillations, ENSO events and as well as global warming. As mentioned above, this paper also proposes some related key issues such as understanding changes in the property of precipitation and mechanisms for precipitation persistency and phase, and their linkages to the global warming. Such kinds of study are expected to enhance our understanding of climatic changes in China's precipitation and improve our knowledge on changes in extreme weather and climate events in a warming world.