The Assimilation and Modeling Branch (AMB) is home to much of the research
in NOAA/ESRL/GSD on weather model and data assimilation development for operational forecasting
and impact studies for new observing systems.
Rapid Update Cycle
An integrated high-frequency model/assimilation system (RUC) is developed
by scientists in AMB in coordination with NOAA/NCEP to support NWS,
other components in NOAA, and the aviation community including FAA
with accurate short-range forecasts based on latest hourly observations.
AMB scientists improve the RUC high-resolution model and physical parameterizations,
and continually refine the RUC assimilation system.
Rapid Refresh
AMB scientists lead development of the next-generation replacement for the (RUC), the Rapid Refresh (RR). The RR is also an hourly assimilation/model system, like the RUC, and differs from the RUC in that it uses
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an RR-unique version of the Weather Research and Forecast (WRF) model, a community mesoscale forecast model partially developed by AMB,
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an RR-unique version of the Gridpoint Statistical Interpolation (GSI) assimilation system, and
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a larger domain covering all of North America.
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a 3-km nest with hourly updating initialized with radar-enhanced 13-km RUC or RR, called the High-Resolution Rapid Refresh (HRRR). The HRRR provides unique radar-initialized hourly-updated, convection-resolving forecasts, and is currently running over a northeast US regional domain.
WRF-Chem model
AMB is leading the development of a next- generation coupled weather/air quality numerical prediction system based upon the WRF model, called WRF-Chem. Gas-phase chemistry and aerosol processes are tightly coupled to meteorology within the WRF model structure. Since the model also includes the aerosol direct and indirect effect in addition to sophisticated microphysics packages, WRF-Chem can be used for process studies that are extremely relevant for global change predictions. WRF-Chem has a large international user base and, in addition to studying global change processes, is used to predict weather, dispersion, and air quality.
FIM global model - Flow-following Finite-volume Icosahedral Model
AMB scientists lead work with other scientists from NOAA/ESRL toward the development of a new global atmospheric model including the use of the adaptive isentropic-sigma hybrid vertical coordinate successful with the RUC model, accurate finite-volume horizontal grid, and an icosahedral horizontal grid. ESRL collaborates with NCEP/EMC toward application of the FIM model in the NCEP ESMF framework.
Observation impact studies
AMB has also conducted studies of forecast impact from different observing systems. AMB is currently focused on a multi-year impact study for TAMDAR (Tropospheric Airborne Meteorological Reporting) regional commercial aircraft observations. AMB has previously examined the impact of the NOAA profiler network and the GPS ground-based precipitable water network (developed at NOAA/ESRL/GSD).