Welcome to the 28th annual meeting of the World Meteorological Organization's Working Group for Numerical Experimentation, co-sponsored by World Climate Research Program (WCRP) and World Meteorological Organization Commission for Atmospheric Sciences.

The Working Group on Numerical Experimentation (WGNE), jointly established by the WCRP Joint Scientific Committee (JSC) and the WMO Commission for Atmospheric Sciences (CAS), which is responsible for WWRP and GAW, has the responsibility of fostering the development of atmospheric circulation models for use in weather, climate, water and environmental prediction on all time scales and diagnosing and resolving shortcomings (WMO/TD 121). WCRP-JSC/CAS WGNE promotes co-ordinated numerical experimentation for validating model results, observed atmospheric properties, exploring the natural and forced variability and predictability of the atmosphere, (e.g. the Atmospheric Model Intercomparison Project, AMIP), as well as studies aimed at refining numerical techniques, and the formulation of atmospheric physics processes. WGNE also monitors the advances in data assimilation and analysis methods and is the focal point in the WCRP for encouraging and reviewing the reanalysis projects carried out at various centres with fixed state-of-the-art assimilation systems providing a multi-year homogenous data set for a range of atmospheric and climate diagnostic studies.