Seminar: Global Data Assimilation Plans at NCEP - The Transition to JEDI and Coupled DA

Abstract:

Currently, the Global Data Assimilation System (GDAS) at the National Centers for Environmental Prediction (NCEP) uses the Gridpoint Statistical Interpolation (GSI) software for computing operational analyses. As part of the transition to the Unified Forecast System (UFS), GSI is slated to be replaced by a Unified Data Assimilation (UDA) framework based on the Joint Effort for Data assimilation Integration (JEDI). Led by the Joint Center for Satellite Data Assimilation (JCSDA), groups from NOAA, NASA, the US Navy and Air Force, and the UK MetOffice all contribute to development and testing of JEDI software. Efforts are underway at NCEP on replacing all GSI-based assimilation components with JEDI-based components for a future implementation of the GDAS. Concurrent with the transition to new software infrastructure, NCEP is developing capabilities for coupled Earth system modeling and data assimilation (atmosphere, ocean, sea-ice, land, and composition), with the hope that UFS and JEDI will accelerate scientific innovations on this front. In this presentation, an overview of current validation and transition activities will be presented as well as results from initial testing of weakly-coupled data assimilation and prototype cycled systems in preparation for an upcoming version of the Global Forecast System (GFS).