These model output of firn air content (FAC) and surface mass balance (SMB) are from version 1.0 of the open-source Glacier Energy and Mass Balance model. GEMB is a column model of ice sheet and glacier surface-atmospheric energy and mass exchange as well as firn state. GEMB has been integrated into the open-source Ice-Sheet and Sea-level System Model which can be downloaded at https://issm.jpl.nasa.gov/. Here, GEMB is forced with 3-hourly ERA5 output from 1979 through end of 2024. For Greenland and its periphery, the ERA5 surface temperature and downwelling longwave radiation forcing are spatially bias-corrected for each month. All values are adjusted by the difference between the RACMO2.3 and the ERA5 1980-2015 monthly means. The GEMB output is bilinearly interpolated onto a 10km grid, from the native ISSM grid, and the output is given as 5-day output or as monthly.

Small discontinuities in firn air content variability in v1.0 for dates during 2022 have been fixed in v1.1. For v1.2, the model results have been extended through end of 2022, and periphery glaciers have been added to Greenland. The v1.3 release is the extension of v1.2 through the end of 2023, and the Greenland mask is updated to distinguish between periphery glaciers and the ice sheet. For v1.3, a 5-day output file, v1.3-5day, is also released. The v1.4 product extends the monthly and the 5-day output through the end of 2024.