Silva Patrícia S, Geirinhas João L, Lapere Rémy, Laura Wil, Cassain Domingo, Alegría Andrés, Campbell Jayaka
Instituto Dom Luiz (IDL), Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016, Lisboa, Portugal.
Instituto Dom Luiz (IDL), Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016, Lisboa, Portugal.
J Environ Manage. 2022 Dec 1;323:116193. doi: 10.1016/j.jenvman.2022.116193. Epub 2022 Sep 20.
The Pantanal biome, at the confluence of Brazil, Bolivia and Paraguay, is the largest continental wetland on the planet and an invaluable reserve of biodiversity. The exceptional 2020 fire season in Pantanal drew particular attention due to the severe wildfires and the catastrophic natural and socio-economic impacts witnessed within the biome. So far, little progress has been made in order to better understand the influence of climate extremes on fire occurrence in Pantanal. Here, we evaluate how extreme hot conditions, through heatwave events, are related to the occurrence and the exacerbation of fires in this region. A historical analysis using a statistical regression model found that heatwaves during the dry season explained 82% of the interannual variability of burned area during the fire season. In a future perspective, an ensemble of CORDEX-CORE simulations assuming different Representative Concentration Pathways (RCP2.6 and RCP8.5), reveal a significant increasing trend in heatwave occurrence over Pantanal. Compared to historical levels, the RCP2.6 scenario leads to more than a doubling in the Pantanal heatwave incidence during the dry season by the second half of the 21st century, followed by a plateauing. Alternatively, RCP8.5 projects a steady increase of heatwave incidence until the end of the century, pointing to a very severe scenario in which heatwave conditions would be observed nearly over all the Pantanal area and during practically all the days of the dry season. Accordingly, favorable conditions for fire spread and consequent large burned areas are expected to occur more often in the future, posing a dramatic short-term threat to the ecosystem if no preservation action is undertaken.
潘塔纳尔生物群落位于巴西、玻利维亚和巴拉圭的交汇处，是地球上最大的大陆湿地，也是生物多样性的宝贵保护区。2020年潘塔纳尔异常的火灾季节因严重野火以及该生物群落内目睹的灾难性自然和社会经济影响而备受关注。到目前为止，在更好地理解极端气候对潘塔纳尔火灾发生的影响方面进展甚微。在此，我们评估极端炎热条件（通过热浪事件）如何与该地区火灾的发生和加剧相关。使用统计回归模型进行的历史分析发现，旱季的热浪解释了火灾季节烧毁面积年际变化的82%。从未来角度看，一组假设不同代表性浓度路径（RCP2.6和RCP8.5）的CORDEX-CORE模拟显示，潘塔纳尔地区热浪发生呈显著增加趋势。与历史水平相比，RCP2.6情景到21世纪下半叶导致潘塔纳尔旱季热浪发生率增加一倍多，随后趋于平稳。相比之下，RCP8.5预测热浪发生率将持续增加直至本世纪末，这表明将出现一种非常严峻的情景，即几乎在整个潘塔纳尔地区以及旱季的几乎所有日子都会出现热浪天气。因此，未来火灾蔓延的有利条件以及随之而来的大面积烧毁区域预计会更频繁出现，如果不采取保护行动，将对生态系统构成巨大的短期威胁。
