Unified Model (UM)

Model description

The Met Office Unified Model (UM) vn11.0 is made of the Global Atmosphere 7.1 and JULES Global Land 7.0 described in Walters et al. (2017). The UM dynamical core ENDGame uses a semi-implicit semi-Lagrangian formulation to solve the non-hydrostatic, fully-compressible deep-atmosphere equations of motion (Wood et al., 2014).The model is forced with climatological distributions of aerosol and ozone.

Data structure

Horizontal

The model uses the regular grid N2560. This grid has 2N points zonally, and 3*N/2 points meridionally, i.e dx(equator)=8km and dx(mid-lat) = 5km.

Vertical

The model uses 85 vertical levels with 50 levels below 18 km and 35 levels above this and a fixed model lid 85 km above sea level.

Data

Initialisation and Boundary conditions

Soil Initialisation

Input Data

UM will use the provided grib file with IFS data from 01 Aug 2016.

Treatment of SST and Sea Ice

UM will use the provided IFS data (7 day means).

See also