An Evaluation of an Operational Mesoscale Meteorological Model in Predicting Surface Wind Fields and Temperatures Over Complex Terrain and Coastal Regions of the Northeastern U.S.

摘要

The Regional Atmospheric Modeling System (RAMS4.28) was applied over the New England region in the northeastern U.S. A three month time period from June 1, 1999 to August 31, 1999 was examined by running the meteorological model in a diagnostic hindcast mode. Hourly re-analysis fields produced at the surface (10 meters) and at 24 upper levels of the atmosphere to 13800 meters were archived on two horizontal spatial grids at 9 km and 3 km resolution. This paper presents details of model inputs and procedures used in the re-analysis, and also describes the methodology used to evaluate model predicted fields against an extensive evaluation data set. The data set used for evaluation is comprised of data from 20 surface meteorological measurement sites located in the 3 km domain and 63 surface sites located in the 9 km domain. 4 upper air rawindsonde measurement sites on the 9 km domain were also used in a limited evaluation of the model winds through the boundary layer. The focus of the evaluation is primarily on the surface fields. Surface measurements included data from ASOS sites in the NWS network as well as data from a few sites in the local MESONET network Model performance is described through statistical analyses of hourly surface wind speed and direction and also hourly surface temperature and pressure. A comparison of wind speed and direction is also presented for selected upper air levels. Measurement sites used are characterized and evaluations are performed for measurements from subsets of sites with similar characteristics as well as from all sites in the domain. A comparison of the RAMS4.28 re-analysis results at the grid resolutions of 3 km and 9 km is also made to results of 80 km archived ETA model predictions from the Eta Data Assimilation System (EDAS) at coincident surface sites.