Extreme precipitation events are becoming less frequent but more intense over Jeddah, Saudi Arabia. Are shifting weather regimes the cause?
Extreme precipitation events are becoming less frequent but more intense over Jeddah, Saudi Arabia. Are shifting weather regimes the cause?
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沙特阿拉伯吉达的极端降水事件变得越来越少，但越来越强烈。
DOI：
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发表时间：
2020
影响因子：
3
通讯作者：
I. Hoteit
中科院分区：
文献类型：
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作者：
Thang Luong;H. Dasari;I. Hoteit
这项研究分析了沙特阿拉伯吉达的极端降雨事件与阿拉伯半岛天气尺度的天气模式之间的联系。平均降雨量呈减少趋势；然而，下雨天数有所增加。有趣的是，极端降雨的频率正在减少，但强度却有所增加。在这里，我们利用自组织地图（SOM）来识别最强雨天的天气模式以及导致吉达地区极端降雨的天气系统。确定了在较冷的月份（11 月至 4 月）期间导致吉达强降雨事件的三种主要天气模式，它们都反映了热带与温带之间的相互作用。早期（1979-1998年）极端事件的特点是较强的热带影响和局地降水模式，而后期（1999-2018年）则有较强的温带强迫和较高的极端降雨量。我们的研究结果表明，近几十年来，导致吉达市极端降雨的机制已经转向具有更强温带影响的天气状况。
This study analyses the connection between extreme rainfall events in Jeddah, Saudi Arabia, and synoptic‐scale weather patterns over the Arabian Peninsula. Mean rainfall follows a decreasing trend; however, the number of rainy days has increased. Interestingly, extreme rainfall is becoming less frequent but shows an increased intensity. Here we utilize self‐organizing maps (SOMs) to identify the weather patterns of the most intense rainy days and the synoptic systems causing extreme rainfall in the Jeddah region. Three main weather patterns that cause heavy rainfall events over Jeddah during the cooler months (November–April) are identified, all reflect tropical‐extratropical interactions. Extreme events in the early period (1979–1998) are characterized by a stronger tropical influence and local precipitation patterns, while a stronger extratropical forcing and higher extreme rainfall amounts are spotted in the late period (1999–2018). Our results suggest that in recent decades, the mechanism causing extreme rainfall over the city of Jeddah has shifted toward a weather regime with stronger extratropical influence.