Development of a Livestock Odor Dispersion Model: Part II. Evaluation and Validation

ABSTRACT A livestock odor dispersion model (LODM) was developed to predict odor concentration and odor frequency using routine hourly meteorological data input. The odor concentrations predicted by the LODM were compared with the results obtained from other commercial models (Industrial Source Complex Short-Term model, version 3, CALPUFF) to evaluate its appropriateness. Two sets of field odor plume measurement data were used to validate the model. The model-predicted mean odor concentrations and odor frequencies were compared with those measured. Results show that this model has good performance for predicting odor concentrations and odor frequencies. IMPLICATIONS This study provides an evaluation and validation for a newly developed LODM. Two sets of field odor plume measurement data were used. Agreement fractional bias values were applied to compare modeled predicted odor intensities and measured intensities. Fac2 (the percentage of the predictions within a factor of 2 of the observed values) and defined Ran0.1 and Ran0.2 values (the percentage of the predictions within a range of ±0.2 and ±0.1, respectively, of the observed values) were used to validate the model performance of predicting odor frequency.