Dispersion model input parameters from numerical weather prediction or synoptic observations

Regulatory dispersion modelling uses hourly synoptic observations (OBS) from a nearby station. Alternatively, hourly Numerical Weather Prediction (NWP) data are useable in air quality management. In parallel runs, OBS data and NWP (two grid scales, ~60 km and ~12 km) were input to the meteorological pre-processor of the Met Office NAME III dispersion model. Frequency distribution results for dispersion parameters including wind speed, friction velocity, heat flux, Monin Obukhov length and Boundary Layer Depth (BLD) have been analysed because they influence dispersion calculations. New stability maps compared dispersion climatology from NWP with pre-processor results using OBS data.