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.

Implemented: 10 December 1996