Global geodatabase of mountain glacier extents at the Last Glacial Maximum

Mountain regions are essential for understanding Earth’s climatic history, as their glacial cycles have shaped landscapes, ecosystems, and regional climates during the Quaternary, leaving behind palaeoglacier records that reveal past climate dynamics. Particularly, mountain glaciers respond sensitively to climatic changes, making them crucial for understanding regional and local climate variations. This higher sensitivity is evident once the maximum glacial extent in mountains often occurred outside the global Last Glacial Maximum (26–19 kyr BP). However, existing global palaeoglacier databases (e.g. Ehlers et al, 2011) have not been updated to incorporate palaeoglaciers reconstructed in the last decade. 

We present a new open-access global geodatabase of mountain glacier extents for the LGM. This synthesis integrates ice-extent reconstructions from 224 studies across 271 mountain ranges globally, standardising over 14,700 individual glacier reconstructions into a geodatabase covering the period 57-14 kyr BP. We implemented a mountain range classification system, compiled metadata from each publication, and linked each reconstruction to its original sources. This effort has updated the state of knowledge in 157 mountain ranges, added 9,450 new reconstructions, and identified a gap in research in 114 mountain ranges.  

Our geodatabase is a powerful resource for investigating regional past climate variability, mountain landscape evolution, and ecological impacts of glaciations. It provides glacier masks for validating glacier modelling and offers spatial boundaries for paleoecological reconstructions of mountain ecosystems. Furthermore, it identifies understudied regions, guiding future work in Quaternary science. We anticipate releasing the database soon with the corresponding publication and website, along with detailed methodology and guidelines for further use.