Study of the WRF Performance for the Most Appropriate Apple Tree’s and Wheat Spraying Time

Document Type : Original Article

Authors

Abstract

Accurate forecast of spray scheduling is the most important agricultural operations which reduce costs, number of spraying times, amount of toxic used and amount of pollutants released into the air and hence environmental risk in agricultural operations. Appropriate time for agricultural spraying operations depend on temperature, wind speed, and precipitation. In this study output of the WRF model was used to predict the above mentioned fields for a six months period. Furthermore, the appropriate time has been predicted to spray and results have been verified as well. Verification results show that Proportion Correct, Threat Score, Bias, and False Alarm Ratio .In order to determine each prediction's parameter in last result of three experiments; observational amounts were substituted instead of model's output. Moreover, results show that if observational value of precipitation be substituted instead of models’ values, parameter's values which mentioned above are improved. In other words, the precipitation and its predictions' accuracy play the most superior role in order to reach to accuracy determining Pesticide’s Time Forecasts. After Post processing the direct model output for precipitation, verification and Improved results are presented. 

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