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Inline WRF-HYSPLIT Coupling

HYSPLIT was originally designed to run offline utilizing meteorological data such as are provided by WRF-ARW. A new model framework has been developed that the revised HYSPLIT model is coupled inline with WRF-ARW to take advantage of the higher temporal frequency of the meteorological variables produced by the meteorological model, as well as using WRF-ARW's vertical coordinate scheme. The inline coupling approach is a more consistent depiction of the state of the atmosphere available to the dispersion model through the elimination of the need to interpolate the meteorological fields temporally and vertically.

Inline coupling flow chart

The evaluation was done by comparing inline and offline results with measurements from two controlled experiments - CAPTEX in the regional scale and ASCOT in the fine scale. The results between the two approaches were very similar for all six releases in CAPTEX. However, for the ASCOT experiments, the cumulative statistical score of the inline simulations was better than or equal to offline runs in four out of five releases. While the use of the inline approach did not provide any advantage over the offline method for the regional scale dispersion represented by the CAPTEX experiment, it was able to improve the simulation for the fine spatial and temporal resolution over the complex terrain area represented by the ASCOT experiment.

For more information:

Instructions for downloading the inline WRF-HYSPLIT:

Modified: January 6, 2017
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