Evaluation of the effect of meteorological data resolution on Lagrangian particle dispersion simulations using the ETEX experiment

Abstract This paper presents results from a series of numerical experiments designed to evaluate operational long-range dispersion model simulations, and to investigate the effect of different temporal and spatial resolution of meteorological data from numerical weather prediction models on these simulations. Results of Lagrangian particle dispersion simulations of the first tracer release of the European Tracer Experiment (ETEX) are presented and compared with measured tracer concentrations. The use of analyzed data of higher resolution from the European Center for Medium-Range Weather Forecasts (ECMWF) model produced significantly better agreement between the concentrations predicted with the dispersion model and the ETEX measurements than the use of lower resolution Navy Operational Global Atmospheric Prediction System (NOGAPS) forecast data. Numerical experiments were performed in which the ECMWF model data with lower vertical resolution (4 instead of 7 levels below 500 mb), lower temporal resolution (12 h instead of 6 h intervals), and lower horizontal resolution (2.5° instead of 0.5°) were used. Degrading the horizontal or temporal resolution of the ECMWF data resulted in decreased accuracy of the dispersion simulations. These results indicate that flow features resolved by the numerical weather prediction model data at approximately 45 km horizontal grid spacing and 6 h time intervals, but not resolved at 225 km spacing and 12 h intervals, made an important contribution to the long-range dispersion.

[1]  Michael D. Moran,et al.  Evaluation of a Mesoscale Atmospheric Dispersion Modeling System with Observations from the 1980 Great Plains Mesoscale Tracer Field Experiment. Part II: Dispersion Simulations , 1996 .

[2]  Evaluation of two pollutant dispersion models over continental scales , 1995 .

[3]  M. Trainer,et al.  Nocturnal Wind Structure and Plume Growth Rates Due to Inertial Oscillations , 1997 .

[4]  Ying-Hwa Kuo,et al.  Eulerian Simulation of Tracer Distribution during CAPTEX , 1988 .

[5]  T. J. Sullivan,et al.  Atmospheric Release Advisory Capability , 1983 .

[6]  F. Girardi,et al.  The European Tracer Experiment Description and Summary of the ETEX Project , 1998 .

[7]  R. Lange,et al.  Chernobyl source term, atmospheric dispersion, and dose estimation. , 1988, Health physics.

[8]  Modeling the wind-fields of accidental releases by mesoscale forecasting , 1997 .

[9]  E. F. Bradley,et al.  Flux-Profile Relationships in the Atmospheric Surface Layer , 1971 .

[10]  F. Girardi,et al.  The European Tracer Experiment Experimental Results and Database , 1998 .

[11]  R. Lange.  Transferability of a three-dimensional air quality model between two different sites in complex terrain , 1989 .

[12]  Roger A. Pielke,et al.  Influence of diurnal and inertial boundary-layer oscillations on long-range dispersion , 1988 .

[13]  T. Hogan,et al.  The Description of the Navy Operational Global Atmospheric Prediction System's Spectral Forecast Model , 1991 .

[14]  J. Nasstrom,et al.  Atmospheric Release Advisory Capability: Real-Time Modeling of Airborne Hazardous Materials , 1993 .