Extreme wildfire events in recent years are shaking our established knowledge of how fire regimes respond to climate variables and how societies need to react to fire impacts. Albeit fires are stochastic and extreme in nature, the speed, intensity, and extension of new extreme fires that have occurred during the last years are unprecedented. Here, we identify common features of these emerging novel extreme wildfire events characterized by very high fire intensity and rapid rates of spread, and we review the major mechanisms behind their occurrence. We then point to the major challenges that extreme wildfire events pose to science and societies worldwide, both today and in the future. Climate change and other factors are contributing to more flammable landscapes and the promotion of unstable atmospheric conditions that ultimately promote wildfire development. Anticipating these novel conditions is a key scientific challenge with paramount implications for present and future fire management, ecosystems, and human well-being.

近年来，极端的野火事件动摇了我们关于火灾状况如何应对气候变量以及社会如何应对火灾影响的公认知识。尽管大火本质上是随机的和极端的，但最近几年发生的新的极端火的速度，强度和范围是前所未有的。在这里，我们确定了这些新兴的极端野火事件的共同特征，这些极端野火事件具有很高的火势和迅速扩散的特征，并回顾了它们发生的主要机制。然后，我们指出极端野火事件对当今和未来全球科学和社会带来的主要挑战。气候变化和其他因素正在导致更易燃的景观，并加剧了不稳定的大气条件，最终促进了野火的发展。预测这些新情况是一项关键的科学挑战，对当前和未来的火灾管理，生态系统和人类福祉具有至关重要的意义。