Abstract ID: 3.12174 | Accepted as Talk | Talk/Oral | TBA | TBA

Sublimation is a key but poorly quantified water flux linking the atmosphere, cryosphere and the hydrosphere. Snowpack water is sublimated into water vapor, thereby bypassing runoff, soil and groundwater recharge, with significant implications for water management in snow-dominated landscapes. Large-scale quantification of sublimation remains challenging due to logistical constraints in remote cold regions and limited data synthesis efforts.
Here, we present sublimation estimates from >100 sites in the Northern Hemisphere from the FLUXNET, AMERIFLUX and ICOS networks. These sites, selected from >500 ecosystem monitoring sites, have seasonal snow-cover and at least 3 winters of latent heat measurements and include diverse land-use types (e.g., forests, wetlands, grasslands, croplands, etc.). By intersecting winter latent heat estimates at these sites with snow albedo, temperature, and remote sensing proxies (e.g., Normalized Difference Snow Index, NDSI), we estimate that sublimation could be as high as 15% of annual precipitation for many of these sites. We further compare these estimates with Earth System Model (ESM) simulations and assess the sensitivity of sublimation estimates to atmospheric drivers, including temperature, wind speed, and vapor pressure deficit.