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Time series of 12 months running window averaged SWE for ERA5 (blackblue) and ERA5Snow (cyan) and ERAland (redpink)
Global and North America: Clear stepwise negative trend in 2004 in ERA5 due to absence/activation of IMS assimilation before/from 2004. ERA5snow and ERA5;and have similar trend but with no data assimilation ERA5land has more snow than ERA5snow which assimilates in situ observations
Europe: not strong impact of IMS activation in 2004, due to well constrained snow analysis by dense in situ observations. Similar trend the three products
References:
Arduini G., G. Balsamo, E. Dutra, J. Day, I. Sandu, S. Boussetta, T. Haiden Impact of a Multi‐Layer Snow Scheme on Near‐Surface Weather Forecasts, Journal of Advances in Modeling Earth Systems n. 12, pp. 4687–4710.
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