Resumen
Infrared radiation data for the period 1980-1987 obtained at the Solar Radiation Observatory of the Institute of Geophysics of the National University of Mexico, is analyzed with the help of empirical and theoretical models for the transfer of long wave radiation. Model results and measurements agree for the years of 1980-1982 For later years there are differences between calculations and data, increasing year after year. These results indicate that measurements are not reliable from mid-1982 and on, the reason being that there are no physical causes for a monotonous increase in infrared radiation starting in 1982. Using the good data we have adjusted Swinbank's formula to different seasons (Mexico City), by using different constants. This allows a better determination of the surface fluxes. With these empirical and theoretical formulas we have corrected the data, for the whole period The anomaly of 1982, 1983 (year of El Chichon and El Nino) becomes apparent.