The differing role of weather systems in southern Australian rainfall between 1979–1996 and 1997–2015
The differing role of weather systems in southern Australian rainfall between 1979–1996 and 1997–2015
复制标题
1979-1996年和1997-2015年天气系统对澳大利亚南部降雨量的不同作用
作者：
A. Pepler;A. Dowdy;P. Hope
澳大利亚南部的大部分降雨都与气旋、冷锋和雷暴有关，当这些天气系统同时发生时，特别有可能导致极端降雨。澳大利亚南部部分地区在近几十年来的冷半年降雨量下降，以前被归因于锋面和/或气旋的降雨量减少，而雷暴相关的降雨量则被观察到增加，特别是在温暖的半年。然而，这些系统的同时出现，特别是气旋或锋面与雷暴的同时出现，可能对某些地区的降雨，特别是暴雨非常重要，而这些组合天气系统的频率变化以前没有评估过。在本文中，我们表明，在1979-1996年和1997-2015年期间，澳大利亚东南部观测到的大部分冷季降雨量下降与产生降雨的锋面和气旋频率的减少有关，而同时冷锋和雷暴的频率增加，在某些地区不产生降雨。澳大利亚南部大部分地区的雷暴降雨量有所增加，特别是在温暖的半年，包括雷暴环境与气旋或锋面同时发生的降雨量增加。
Most of the rainfall in southern Australia is associated with cyclones, cold fronts, and thunderstorms, and cases when these weather systems co-occur are particularly likely to cause extreme rainfall. Rainfall declines in some parts of southern Australia during the cool half of the year in recent decades have previously been attributed to decreases in the rainfall from fronts and/or cyclones, while thunderstorm-related rainfall has been observed to increase, particularly in the warm half of the year. However, the co-occurrence of these systems, particularly the co-occurrence of cyclones or fronts with thunderstorms, can be very important for rainfall in some areas, particularly heavy rainfall, and changes in the frequency of these combined weather systems have not been previously assessed. In this paper we show that the majority of the observed cool season rainfall decline between 1979–1996 and 1997–2015 in southeast Australia is associated with a decrease in the frequency of fronts and cyclones that produce rainfall, while there has simultaneously been an increase in the frequency of cold fronts and thunderstorms that do not produce rainfall in some regions. Thunderstorm rainfall has increased in much of southern Australia, particularly during the warm half of the year, including an increase in rainfall where a thunderstorm environment occurs at the same time as a cyclone or front.
影响因子：
5.2
作者：
Hawcroft, M. K.;Shaffrey, L. C.;Dacre, H. F.
通讯作者：
Dacre, H. F.