...
Time series of 12 months running window averaged SWE for ERA5 (blue) and ERA5Snow (cyan) and ERAland (pink). Also included offline ERA5-Land re-run at the ERA5 resolution with single layer (black) and multi-layer snow model (red).
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
...