An Update on the Implementation of a Fire Behavior Model in the Unified Forecast System

In recent years we have been working on implementing a fire behavior model in the Unified Forecast System (UFS). The fire behavior model is an enhanced version of the WRF-Fire modules and we refer to it as the Community Fire Behavior model (CFBM). The model is available as a national unified operational prediction capability (NUOPC) for coupling with UFS. The interactions with the atmosphere are two ways, in which surface winds and other near surface variables are passed into the fire model, and the fire produced heat and moisture fluxes feedback into the atmosphere. In this way, one is able to perform coupled fire-atmosphere simulations with the UFS model. Smoke resulting from fuel consumption is also released, advected, and diffused as a tracer, and in the future, it can be linked to radiation and cloud processes. Fire simulations performed with UFS and WRF-Fire produce consistent results, validating our development and implementation of the CFBM, the NUOPC layer, and its coupling to UFS-Atmosphere. The CFBM and NUOPC layer are available as open source code, and the process to incorporate the rest of developments into the public UFS repositories is underway. When complete, one should be able to configure and run the coupled fire-atmosphere model from the short range weather application for fundamental and applied research with UFS involving fire-weather interactions.