ESMF coupling between WRF TL-ADJ and WRF-Var Data Assimilation
The goal of the current work is to increase the performance and stability of the WRF 4DVAR data assimilation system by reworking the three concurrent executables of the 4DVAR system into a single executable sequential/concurrent hybrid-code by use of the ESMF (http://www.esmf.ucar.edu/) coupling framework.
1. Familiarization with the WRFDA, WRFNL, and WRFPLUS code and build system, specifically the top level drivers, in order to design the interlacing of the driver calls necessary to convert the code from a concurrent system into a sequential system.
2. Updated the legacy ESMF stubs in the three WRF components, which were designed around the ESMF v2 series, to work with the more recent ESMF releases (ESMF 3.1+ series).
2. Built a simple three component driver/wrapper for the WRF 4D VAR components, still excluding an internal coupler. The driver is designed to run the Var and Plus components concurrently, while the NL component runs sequentially with the Var and Plus components. This allows both the Var and Plus components to concurrently process the third phase of the 4D var computation, allowing a potential improvement to performance.
3. Added the init, run, and finialize processes for the first two (Var and NL) of three 4D var components to the driver.
Currently, testing this work before continuing to integrate the third 4D var component (Plus).