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野火前体在不同的时间尺度上显示了互补的可预测性
Yuquan Qu1, Diego G Miralles2, Sander Veraverbeke3
1Institute of Bio- and Geosciences: Agrosphere (IBG-3), Forschungszentrum Jülich GmbH, Jülich, Germany. y.qu@fz-juelich.de.
Nature communications
|October 26, 2023
概括
在全球范围内,野火状况正在增加. 这项研究揭示,天气模式 (上下) 比燃料条件 (自下而上) 更多地驱动野火,影响气候反和管理策略.
科学领域:
- 环境科学 环境科学
- 气候科学 气候科学
- 生态生态学 生态生态学
背景情况:
- 全球气温上升和天气模式的变化正在创造更频繁的野火条件.
- 野火释放出大量的净碳排放,有助于形成需要监测和预测的积极气候反循环.
- 了解野火的驱动因素对于有效的气候变化减缓和土地管理至关重要.
研究的目的:
- 用因果推断方法调查天气 (自上而下) 和燃料 (自下而上) 前体对野火发生的影响.
- 为了区分由上下而下主导的地区与自下而上的野火驱动者.
- 确定燃料管理最有效的领域,并评估不同类型的前体的互补可预测性.
主要方法:
- 应用因果推理方法来分析天气变量和燃料条件与野火事件之间的关系.
- 空间分析以确定全球不同地区的主导前体类型 (上下或下下向上).
- 评估两种前体类型在各种时间尺度上的预测能力.
主要成果:
- 在分析的地区中,73.3%的天气前体主导着野火驱动因素,而自下而上的燃料前体占比为26.7%.
- 热带雨林,中度和西伯利亚东部北极森林中普遍存在自上而下的统治.
- 北美和欧洲的北极森林,非洲和澳大利亚的萨凡纳中,自下而上的前体占主导地位.
结论:
- 野火点火主要受全球天气模式的影响,但燃料条件在北极森林和大草原等特定生态系统中至关重要.
- 确定受燃料状况影响的地区,可以制定有针对性的,可能更有效的燃料管理策略.
- 顶向下和底向上的前体都为不同时间尺度的野火提供了互补的预测能力,而底向上的前体可以在某些地区进行季节性或跨年预测.
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