No single factor produces wildfires; rather, they occur when fire thresholds (ignitions, fuels, and drought) are crossed. Anomalous weather events may lower these thresholds and thereby enhance the likelihood and spread of wildfires. Climate change increases the frequency with which some of these thresholds are crossed, extending the duration of the fire season and increasing the frequency of dry years. However, climate-related factors do not explain all of the complexity of global fire-regime changes, as altered ignition patterns (eg human behavior) and fuel structures (eg land-use changes, fire suppression, drought-induced dieback, fragmentation) are extremely important. When the thresholds are crossed, the size of a fire will largely depend on the duration of the fire weather and the extent of the available area with continuous fuels in the landscape.

中文翻译：

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野火和全球变化

没有任何一个因素会引发野火；相反，它们发生在跨越火灾阈值（点火、燃料和干旱）时。异常天气事件可能会降低这些阈值，从而增加野火的可能性和蔓延。气候变化增加了跨越这些阈值的频率，延长了火灾季节的持续时间并增加了干旱年份的频率。然而，气候相关因素并不能解释全球火势变化的所有复杂性，因为改变的点火模式（例如人类行为）和燃料结构（例如土地利用变化、灭火、干旱引起的枯死、碎片）是极其重要。当跨过门槛时，