A model for the solar radiation budget of the northern hemisphere: Comparison with Earth Radiation Budget Experiment data

Abstract

A simple atmospheric radiation transfer model was used with climatological data to predict the mean monthly‐zonal (10° latitudinal zones) solar radiation budget at the Earth's surface and at the top of the atmosphere for the northern hemisphere. The model also computes the amount of energy absorbed by the atmosphere. The model's outgoing fluxes agree within 5 W m−2 on average with the corresponding values determined from the Earth Radiation Budget Experiment (ERBE) (1985–1989) satellite data. Comprehensive measurements of the surface radiation budget for all zones and months are not available to validate the model predictions. However, the validation of the model for the top‐of‐atmosphere radiation budget engenders more confidence in the model's surface radiation budget than would be the case if the model used the ERBE outgoing fluxes as input data. The model gives a mean planetary albedo for the northern hemisphere of 0.306 compared with 0.297±0.007 from the 5 years of ERBE data and a flux‐mean surface albedo of 0.12 which agrees well with 0.13 from observations. The percentage of the hemispherical mean incoming solar radiation that is absorbed by the atmosphere is computed to be 25% while that absorbed at the surface is 44%, in agreement with the results of other models.