The Met Office Unified Model Global Atmosphere 6.0/6.1 and JULES Global Land 6.0/6.1 configurations
- 1Met Office, FitzRoy Road, Exeter, EX1 3PB, UK
- 2Centro de Investigación Científica y de Educación Superior de Ensenada, Departamento de Oceanografía Física, Carretera Ensenada-Tijuana 3918, Ensenada BC 22860, Mexico
- 3National Centre for Atmospheric Science, Department of Meteorology, University of Reading, Reading, RG6 6BB, UK
- 4Max Planck Institute for Meteorology, Bundesstrasse 53, 20146 Hamburg, Germany
Abstract. We describe Global Atmosphere 6.0 and Global Land 6.0 (GA6.0/GL6.0): the latest science configurations of the Met Office Unified Model and JULES (Joint UK Land Environment Simulator) land surface model developed for use across all timescales. Global Atmosphere 6.0 includes the ENDGame (Even Newer Dynamics for General atmospheric modelling of the environment) dynamical core, which significantly increases mid-latitude variability improving a known model bias. Alongside developments of the model's physical parametrisations, ENDGame also increases variability in the tropics, which leads to an improved representation of tropical cyclones and other tropical phenomena. Further developments of the atmospheric and land surface parametrisations improve other aspects of model performance, including the forecasting of surface weather phenomena.
We also describe GA6.1/GL6.1, which includes a small number of long-standing differences from our main trunk configurations that we continue to require for operational global weather prediction.
Since July 2014, GA6.1/GL6.1 has been used by the Met Office for operational global numerical weather prediction, whilst GA6.0/GL6.0 was implemented in its remaining global prediction systems over the following year.