Escalate Dry-hot compounded fires threaten Eurasian drylands

Compound climate extreme events has inflicted enormous damage since it amplifies their impacts on societies and ecosystems. However, it remains challenging to quantify its interaction and influences due to the vulnerability of drylands. We quantified the spatial and temporal pattern change, climate drivers of fire during 2001-2020 and investigated the interaction between the dry-hot conditions and fire events. The results show that fires mostly occurred in spring and autumn among three typical hotspots located in Southern of the East Europe and Central Asia, northeastern of East Asia, and Indian Peninsula. Cropland fires and grassland fires occurred mostly, followed by forest and shrub and savana fires. The average fire burned area decreased by 0.30 km2/yr in the Eurasian dryland during 2001-2020, while dry-hot compounded fires burned area increase in 0.78 km2/yr. Temperature, precipitation and wind are the main explanatory factors, while lighting is the most important variable around the Black Sea. Dry-hot condition in early stage will increase the frequency and intensity of fire, mainly through affecting the fuel flammability and abundance. Our findings highlight the importance to understand the interrelated co-occurring climate extremes, and further efforts for monitoring and take action to reduce its threat.