Variations of the CO2 band intensities in the Mars spectra

The results of terrestrial spectrascopic observations of the Mars in the CO2 absorption bands in the 1.6μ region during 1971-1975 are discussed. Possible reasons Which result in the appearance of variations in equivalent width W values of CO2 bands are considered. They are: pressure dependence on average rise of the visible disc, dependence of W values on the phase angle, seasonal pressure variations and changes of W value as a result of dynamic processes. It is shown that in the course of systematic processes equivalent widths may change almost trofold. The W mean value equals approximately 15 A. Variations of the CO2 band intensities are generally associated with seasonal changes of the total pressure in the Mars atmosphere. Seasonal variations in the dustless atmosphere are almost three times than in the dusty one