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潮湿和干燥极端的复合事件:识别,变化和危险模式
Haiyan Chen1, Ye Tuo1, Chong-Yu Xu2
1Hydrology and River Basin Management, Technical University of Munich, Munich, Germany.
The Science of the total environment
|September 16, 2023
概括
这项研究介绍了复合潮湿和干燥极端 (CWDEs),发现它们在德国增加,特别是在夏季. 热点位于德国南部和柏林附近,气候和地理是关键因素.
科学领域:
- 气候科学 气候科学
- 水文学的水文学
- 环境科学 环境科学
背景情况:
- 复合水文气象极端因素在气候变化下显著影响生态和社会福祉.
- 引入了对比极端的新类别,即混合湿和干极端 (CWDEs).
- 长期干旱事件涉及破坏性的干旱事件 (EDs),随后在特定时间范围内出现潮湿极端事件 (EWs).
研究的目的:
- 为了确定和分析德国的复合湿和干极端 (CWDEs).
- 揭示与CWDEs相关的时空变化和风险模式.
- 了解CWDEs的驱动因素和区域依赖.
主要方法:
- 开发了一个单独的系统来识别相应的ED和EW,考虑到它们的不同过程.
- 峰值超过值和标准化指数方法用于识别EWs (每日) 和EDs (每月).
- 曼-肯德尔测试,普通最小平方和全球/本地莫兰指数被用来分析时空变化和集群.
主要成果:
- 长期发病事件表现出显著的季节性影响,夏季是最脆弱的时期.
- 在德国南部和柏林附近确定了CWDEs的空间热点.
- 历史上观察到CWDEs的强增长趋势,受潮湿的气候和复杂的地理环境的影响.
结论:
- 长期严重疾病带来了一个独特的挑战,具有独特的区域驱动因素:干旱地区占主导地位的潮湿极端,而干旱异常在潮湿地区是关键.
- 了解这些复合事件对于有效的风险减轻和优先考虑脆弱区域至关重要.
- 该研究提供了一个强大的框架和开放式数据,用于进一步研究复合危险.
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