Behaviour of the Weather Research and Forecasting (WRF) model boundary layer and surface parameterizations in one-dimensional simulations during the BAMEX field campaign
Mariusz Pagowski, ESRL/GSD
Atmospheric boundary layer is the bottom layer of the troposphere which is directly affected by the Earth's surface and and which varies on time scales determined by the surface fluxes of momentum, heat and moisture. We spend most of our lives in the boundary layer and it is where our perception of weather and climate occurs. Physical parameterizations of surface and boundary layer processes are essential part of numerical models and their accuracy determines quality of forecasts.
Weather Research and Forecasting (WRF) model is hailed as a next-generation mesoscale weather prediction system and is being developed under a collaborative partnership among NCAR. NCEP, NOAA-GSD, AFWA, NRL, FAA and Oklahoma University. In this talk we attempt an assessment of surface and boundary parameterizations in WRF. To eliminate the accumulation of errors from parameterizations of convection, microphysics, and radiation in the three-dimensional model and elucidate errors of the WRF's surface and the PBL parameterizations we use a one-dimensional model initialized and forced by observations and weather analyses.
We perform 12-hourly simulations with WRF model boundary layer and land surface schemes in summer 2003. The simulations use data collected at the Lamont (OK) ARM site during the BAMEX field campaign during that summer. Vertical profiles from rawinsondes, and soil temperature and moisture from measurements are used for the initializations. External forcings for the model include shortwave and longwave radiation, precipitation rate, and geostrophic wind and are derived from observations and weather analyses. Performance of the surface and boundary layer schemes with respect to winds, temperature, mixing ratio, and surface fluxes is evaluated.
SECURITY: If you are coming from outside the NOAA campus, please be advised that you will need an on-site sponsor. Please contact that person in advance of the seminar to be put on the list and allow 10 minutes extra on the day of the seminar. Please contact Joe Barsugli (303-497-6042) or Lucia Harrop (303-497-6188) at least a day before the seminar if you have any questions.