Where Snow and Forest Meet: A Global Atlas

Abstract

The complex interactions between snow cover and forests have implications for ecosystems, water resources and the Earth's climate. However, the geographic distribution of where snow and forest overlap remains poorly known. Here, we evaluate the importance of snowfall over forested environments and its spatial variability at the global scale and a 0.1° spatial resolution, leveraging an existing climatological reanalysis and a satellite tree cover map. We find that 23% of the land mass (30.5·10⁶ km²) experiences snowfall in forested areas, mostly in the boreal forest (15.8·10⁶ km²) and elsewhere in mountains (4.9·10⁶ km²). There, the solid fraction of precipitation in forest is greater than the median value of 11.1% over 15.3·10⁶ km², reaches 64% locally, and 23% when aggregated over hydrological basins larger than 10⁵ km².