This is the CIRES UGWP V0 driver module.

Collaboration diagram for GFS UGWP V0 Driver Module:

Note for the sub-grid scale orography scheme in UGWP-v0: Due to degraded forecast scores of simulations with revised schemes for subgrid-scale orography effects in FV3GFS, EMC reinstalled the original gwdps-code with updated efficiency factors for the mountain blocking and OGW drag. The GFS OGW is described in the separate section (GFS Orographic Gravity Wave Drag Scheme) and its "call" moved into UGWP-driver subroutine. This combination of NGW and OGW schemes was tested in the FV3GFS-L127 medium-range forecasts (15-30 days) for C96, C192, C384 and C768 resolutions and work in progress to introduce the optimal choice for the scale-aware representations of the efficiency factors that will reflect the better simulations of GW activity by FV3 dynamical core at higher horizontal resolutions. With the MERRA-2 VMF function for NGWs (slat_geos5_tamp_v0) and operational OGW drag scheme (GFS Orographic Gravity Wave Drag Scheme), FV3GFS simulations can successfully forecast the recent major mid-winter sudden stratospheric warming (SSW) events of 2018-02-12 and 2018-12-31 (10-14 days before the SSW onset; Yudin et al. 2019 [194]). The first multi-year (2015-2018) FV3GFS simulations with UGWP-v0 also produce the equatorial QBO-like oscillations in the zonal wind and temperature anomalies.