Improving ERA5-Land soil temperature in permafrost regions

Cao et al. (2020) have previously reported a warm bias in ERA5-Land soil temperature in permafrost regions that was supposedly being caused by an underestimation of the snow density. This study evaluates a new multi-layer snow scheme in the land surface scheme of ERA5-Land, i.e., HTESSEL, with a revised snow densification parametrization. The revised HTESSEL significantly improved the representation of soil temperature in permafrost regions compared to ERA5-Land. The original simulation data, on the Octahedral reduced gaussian grid, were interpolated on a 0.25/0.25 regular lat/lon grid (global) and aggregated in daily mean from 2000-01-01 to 2018-12-31. More information on the dataset is contained in info_dataset.txt