Skip to content

Atmosphere component

Unified Model (UM)

The UK Met Office Unified Model (UM) is a numerical model of the atmosphere used for both weather and climate applications across a wide range of temporal scales (nowcasting to centennial) and spatial scales (sub km convective scale to global). The UM includes solutions of the equations of atmospheric fluid dynamics with advanced parameterisations of physical processes like convection, cloud formation and atmospheric radiation.

Configurations that use UM

The UM is the atmospheric component in many of the ACCESS models used at regional and global scales.
It is included both in ACCESS-CM and ACCESS-ESM configurations.

The Australian Bureau of Meteorology (BoM) uses the UM in its suite of ACCESS forecast systems for daily and seasonal weather, as well as extreme events and emergencies (e.g., bushfires, cyclones, floods, coral bleaching, coastal inundation, etc.).

The UM is used by several international operational meteorology and research organisations, and these contribute towards its development through the UM partnership.


Last update: April 25, 2024