Morton, Don, Kayla Harrison, Arctic Region
Supercommuting Center, University of Alaska, Brad Zavodsky, Shih-Hung Chou,
NASA Short-term Prediction Research and Transition Center, Ming Hu,
Developmental Testbed Center
The Arctic Region
Supercomputing Center has been running a quasi-operational prototype of a High
Resolution Rapid Refresh for Alaska (HRRRAK) at 3km resolution, initialized by
the 13km Rapid Refresh (RR). Although the RR assimilates a broad range of observations
into its analyses, experiments with the HRRRAK suggest that there may be added
value in assimilating observations into the 3km initial conditions, downscaled
from the 13km RR analyses. The NASA Short-term Prediction Research and
Transition (SPoRT) group has been using assimilated data from the Atmospheric
Infrared Sounder (AIRS) in WRF and WRF-Var simulations since 2004 with
promising results. The sounder is aboard NASAÕs Aqua satellite, and provides
vertical profiles of temperature and humidity. The Gridpoint Statistical
Interpolation (GSI) system is then used to assimilate these vertical profiles
into WRF HRRRAK forecasts. In this work, we perform a preliminary assessment of
the use of AIRS data by comparing non-assimilated real-time HRRRAK forecasts
with otherwise identical AIRS-assimilated forecasts.