Estimation of Solar Radiation from Measured Temperatures at Different Time Scales in Chongqing

Solar radiation (R_s), a critical variable in eco-environmental models, is not measured at many meteorological stations. Prediction of Rs has drawn increasing attention in the recent years. The aim of the present research was to conduct a comparative study of estimating R_s from measured maximum and minimum temperature and dew point temperature at daily, five-day, ten-day, monthly time scales. Coefficient of determination (r²), RMSE (root mean square error), and d-index were used to compare the goodness of fit of all the models at different time scales. The rank of goodness of fit of all models at time scales was: daily <; five-day <; ten-day <; monthly. In terms of RMSE and d-index, the newly developed model which contained all variables performed best at all time scales and could be a general radiation estimation model.