Description of the upgrade
The T106 model became operational. The spectral representation in the horizontal is truncated at wavenumber 106. The vertical resolution was not changed.
The vertical diffusion scheme was modified which allows larger time-steps to be used (t = 900s). A parametrisation scheme of shallow cumulus convection has been introduced.
The Kuo cumulus convection scheme has been replaced by a modified Kuo scheme.
Evaporation of large-scale rain and melting of snow have been reformulated.
A new cloud prediction scheme was formulated to overcome the deficiencies of the previous scheme (too many deep clouds, too little tropical cirrus, too little subtropical cloudiness, poor representation of the diurnal variation in cloudiness).
Sea ice has been re-specified and is now assumed to exist whenever sea temperatures are below -2°C (previously 0°C).
Implemented: 01 May 1985
Contents of this page
All IFS cycles
- Terminology for IFS testing
- Implementation of IFS Cycle 48r1
- Implementation of IFS Cycle 47r3
- Implementation of IFS Cycle 47r2
- Implementation of IFS Cycle 47r1
- Implementation of IFS cycle 46r1
- Implementation of IFS cycle 45r1
- Implementation of Seasonal Forecast SEAS5
- Implementation of IFS cycle 43r3
- Implementation of IFS Cycle 43r1
- Implementation of IFS cycle 41r2
- Introducing the octahedral reduced Gaussian grid
- Horizontal resolution increase
- Boundary-Condition Programme ENS at 06 and 18 UTC
- Implementation of IFS Cycle 41r1
- IFS cycle upgrades pre 2015