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地势高度持续的正异常导致欧洲各地的野火活动增加
Kerryn Little1, Dante Castellanos-Acuna2, Piyush Jain3
1School of Geography, Earth and Environmental Sciences, University of Birmingham, Birmingham B15 2TT, UK.
概括
持续的正异常 (PPA) 显著增加了欧洲各地的野火风险. 这些大气模式与极端的火灾天气和更大的烧毁区域有关,有助于早期预警系统.
科学领域:
- 大气科学 大气科学
- 气候学 气候学 气候学
- 野火科学 野火科学 野火科学
背景情况:
- 在500hPa地势高度的持久正异常 (PPA) 是与极端天气事件相关的上空循环模式.
- 这些异常与表面热浪,干旱和燃料干旱有关,这些条件有利于野火.
研究的目的:
- 在泛欧洲范围内检查 PPA 事件与地表火灾天气和烧伤面积之间的关联.
- 了解电力合约在预干燥燃料中的作用及其对野火发生和范围的影响.
主要方法:
- 分析PPA事件及其与欧洲各地极端火灾天气日和野火事件的相关性.
- 与 PPA 相关的泛欧洲燃烧面积的百分比的量化.
- 研究PPA存在,燃烧区域和燃料湿度指数之间的时间关系.
主要成果:
- 在整个欧洲,极端的火灾天气和野火在PPA事件期间的可能性分别是3.5和2.3倍.
- 在2001年至2021年期间,发电合约占泛欧洲燃烧总面积的45%.
- 观察到一个度梯度,北欧在PPA存在后,烧伤面积增加了63%,在PPA存在后一周后,烧伤面积达到峰值.
结论:
- 电力购买协议是欧洲各地野火活动和烧毁面积的重要驱动因素.
- 这些发现支持对野火危险的早期预警系统的开发,提高准备和管理策略.
- 了解PPA的影响对于为政策提供信息和促进跨欧洲资源共享来管理野火至关重要.
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