Rising future tropical cyclone-induced extreme winds in the Mekong River Basin

The societal impact of extreme winds induced by tropical cyclones(TCs)is a major concern in the Mekong River Basin(MRB).Though no clear trend of landfalling TC intensity along the Vietnam coastline has been observed since the 1970 s,climate models project an increasing TC intensity in the 21 st century over the Western North Pacific,which is the primary TC source region influencing the MRB.Yet,how future TC activities will affect extreme winds quantitatively in the MRB remains unclear.By employing a novel dynamical downscaling technique using a specialized,coupled ocean-atmospheric model,shorter return periods of maximum wind speed in the MRB for 2081–2100 compared with 1981–2000 are projected based on five global climate models under the RCP8.5 scenario,suggesting increases in the future tropical cyclone intensity.The results point to consistently elevated future TC-related risks that may jeopardize sustainable development,disrupt food supply,and exacerbate conflicts in the region and beyond.

热带气旋引起的极端风速对社会的影响使得它成为湄公河流域的最大隐患之一.西北太平洋是影响湄公河流域热带气旋的重要源地之一.从20世纪70年代开始,在越南沿岸登陆的热带气旋强度没有呈现明显的变化趋势.然而,气候模式模拟预测显示西北太平洋的热带气旋强度将会在21世纪内增强,届时将很可能影响到湄公河流域.目前为止,未来湄公河流域的热带气旋活动引起的极端风速将会如何变化尚不明确.因此,本文采用了1个基于海洋大气耦合模型的降尺度技术和5个全球气候模式的输出结果对未来湄公河流域的热带气旋活动进行了模拟.结果显示,相比于1981~2000年,在RCP8.5的情境下,2081~2100年湄公河流域热带气旋的最大风速的重现期将显著缩短.这意味着该区域的热带气旋强度将明显增强.此结果预示着未来热带气旋活动将增加相关灾害的发生,并且这可能会在地区乃至全球范围威胁可持续发展、影响粮食供应和加剧冲突.