近日，荷兰阿姆斯特丹自由大学教授Veraverbeke, Sander及其课题组提出，由于雷击火灾，温带森林面临的风险越来越大。相关论文于2023年11月9日发表于国际顶尖学术期刊《自然—地球科学》杂志上。

该研究团队用机器学习的方法对七个地区的着火地点、原因和燃烧面积的参考数据进行分析，以获得闪电和人为点火作为主要着火原因的全球归因。该课题组人员发现，目前在温带完整森林中，77%(不确定性表示为一个标准差= 8%)的烧毁面积是由闪电造成的，每升温1度，这些地区可能会经历11%到31%的闪电。温带森林对全球碳储存具有重要意义，它们目前遭受着与火灾有关的严重森林损失，并且每单位面积的火灾排放量是地球上最大的。因此，未来完整森林中闪电的增加可能会加剧气候变化与温带野火之间的正反馈循环。

据了解，火可以被人点燃，也可以被自然的平静点燃，这几乎完全是雷击。在估计变化的社会经济和气候条件对火灾活动的影响时，区分闪电和人为火灾是至关重要的。

附：英文原文

Title: Extratropical forests increasingly at risk due to lightning fires

Author: Janssen, Thomas A. J., Jones, Matthew W., Finney, Declan, van der Werf, Guido R., van Wees, Dave, Xu, Wenxuan, Veraverbeke, Sander

Issue&Volume: 2023-11-09

Abstract: Fires can be ignited by people or by natural causes, which are almost exclusively lightning strikes. Discriminating between lightning and anthropogenic fires is paramount when estimating impacts of changing socioeconomic and climatological conditions on fire activity. Here we use reference data of fire ignition locations, cause and burned area from seven world regions in a machine-learning approach to obtain a global attribution of lightning and anthropogenic ignitions as dominant fire ignition sources. We show that 77% (uncertainty expressed as one standard deviation=8%) of the burned area in extratropical intact forests currently stems from lightning and that these areas will probably experience 11 to 31% more lightning per degree warming. Extratropical forests are of global importance for carbon storage. They currently experience high fire-related forest losses and have, per unit area, among the largest fire emissions on Earth. Future increases in lightning in intact forest may therefore compound the positive feedback loop between climate change and extratropical wildfires.

DOI: 10.1038/s41561-023-01322-z

Source: https://www.nature.com/articles/s41561-023-01322-z