Coupling Infrastructure Capability in UFS Weather Model

The Unified Forecast System (UFS) is an end-to-end forecast system for the next generation of the National Centers for Environmental Prediction (NCEP) production suite. The UFS weather-model (UWM) comprises the model component of the UFS. It consists of atmosphere, which currently includes the Finite Volume Cubed Sphere (FV3) dynamical core and the Common Community Physics Package, CCPP; ocean, sea ice, wave, land, aerosol, chemistry, and data model components with a central mediator component to couple the components together. The coupling strategy among the components uses the common Earth System Prediction Suite (ESPS) architecture, an Earth System Modeling Framework (ESMF) and National Unified Operational Prediction Capability (NUOPC) based coupling infrastructure framework. The NUOPC interfaces, also called caps, allow each model component to be an independent ESMF grid component. The coupling communication uses either generic NUOPC connectors or the NUOPC compliant Community Mediator for Earth Prediction Systems (CMEPS). This technical note provides details on the coupling capability available in the latest UWM. The model component NUOPC caps and component coupling strategies are documented. The coupled configurations, computational performance, and features that improve the computation performance are also illustrated.