ERA5 and ERA-interim are carried out by two different Integrated Forecast System (IFS) cycles. Therefore, the snowmelt equations used in the HTESSEL parametrisation are different:
- for ERA-Interim, the equations are described in IFS doc Part IV Physical processes, Section 7.4.4, equations 7.40-7.44.
- for ERA5 and CAMS, the equations are described in IFS doc Part IV Physical processes, section 8.4.4, equations 8.51-8.55.