WRFDA Updates for 4.4

WRFDA Version 4.4 was released on April 26, 2022.

New features:

New capability for assimilating GPM GMI radiance data, contributed by Dr. Dongmei Xu at the Nanjing University of Information Science & Technology.

Shen, F., D. Xu, H. Li, J. Min, and R. Liu，2021: Assimilation of GPM Microwave Imager Radiance data with the WRF Hybrid 3DEnVar System for the Prediction of Typhoon Chan-hom (2015), Atmospheric Research. 251, 105422.

New option for surface aerosol data assimilation with MADE-VBS aerosol scheme. The ~doc/README.DA_chem file provides a description for all chemical/aerosol DA options currently available.

Ha, Soyoung, 2022: Implementation of aerosol data assimilation in WRFDA (V4.0.3) for WRF-Chem (V3.9.1) using the MADE/VBS scheme. Geosci. Model Dev., 15, 1769–1788.

Ingest NCEP's satwnd.bufr to assimilate more AMVs that are not included in NCEP's prepbufr file.

The "use_satwnd_bufr" namelist parameter default is true.

Updated features:

Allow to set thinning mesh differently for different conventional observations through a new namelist parameter "thin_conv_opt(num_ob_indexes)". Also reduced memory use for thinning conventional observations.

WRFDA gpsref code has been restructured to moved QC steps in da_get_innov_vector_gpsref.inc to a separate subroutine in a new file da_qc_gpsref.inc. New namelist variables are added to have more flexibility for testing gpsref QC impact. Several issues with gpsref diagnostic output have been fixed and qcstat info for gpsref is now in new qcstat_gpsref_xx. See here for more details.

Bug fixes and enhancements for applications related to offline VarBC (use_background_errors=false), 3DEns-FGAT (num_fgat_time>0 and ensdim_alpha>0 and je_factor=1.0), precondition_cg=true and orthonorm_gradient=true when ensdim_alpha>0, full-ensemble mode (ensdim_alpha>0 and je_factor=1.0). See here for more details.

Enable the assimilation of metop-c AMSU-A and MHS radiances with updated VARBC.in and "radiance info" files.

Bug fixes

For direct assimilation of radar reflectivity, remove the use of "qthres" in the forward operator, which can cause an unrealistic low bound of computed reflectivity. Also simplify the quality control to keep data with both observed and background reflectivity >=rfmin (a namelist parameter).

Fixed a bug in calculating TAMDAR aircraft temperature bias correction.

Fixed memory leaks and runtime crashes due to the missing specification for time info inside chemical DA.

For instructions on compiling and running the latest version of WRFDA, please refer to the updated User's Guide

Helpful links

Compiling WRFDA for 3DVAR

Compiling WRFPLUS and WRFDA for 4DVAR

Running WRFDA

List and description of namelist variables