Wildfires affect 40% of the earth’s terrestrial biome, but much of our knowledge of wildfire activity is limited to the satellite era. Improved understanding of past fires is necessary to better understand how wildfires might change with future climate change, to understand ecosystem resilience, and to improve data-model comparisons. Environmental proxy archives can extend our knowledge of past fire activity. Speleothems, naturally occurring cave formations, are widely used in palaeoenvironmental research as they are absolutely dateable, occur on every ice-free continent, and include multiple proxies. Recently, speleothems have been shown to record past fire events (McDonough et al., 2022). Here we present a review of this emerging application in speleothem palaeoenvironmental science. We give a concise overview of fire regimes and traditional palaeofire proxies, describe past attempts to use stalagmites to investigate palaeofire, and describe the physical basis though which speleothems can record past fires. We then describe the ideal speleothem sample for palaeofire research and offer a summary of applicable laboratory and statistical methods. Finally, we present four case studies which detail [1] the geochemistry of ash leachates, [2] how sulphur may be a proxy for post fire ecological recovery, [3] how a catastrophic palaeofire was linked to changes in climate and land management, and [4] demonstrate that deep caves can record past fire events. We conclude the paper by suggesting that speleothem δ18O research may need to consider the impact of fire on δ18O values, and outline future research directions.
