Description of the upgrade
Model cycle 15r7 was introduced in both the T213 L31 10-day forecast and the EPS
The main features of the new cycle are:
- a two-time level semi-Langrangian scheme
- advection cloud variables
- changes in the snow albedo, expected to reduce the cold bias in 2m temperature in spring
- change to the humidity analysis to eliminate unrealistic drying of the extra-tropical lower stratosphere
- change to the use of SSM/1 sea ice data to eliminate erroneous sea points over permanent ice
- minor change to the model orography and slight adjustments to other fixed surface fields.