The results of measuring the total content of NO₂ by the ERS-2 satellite (GOME instrumentation) in 1996 and in the first half of 1998 are compared to the data of simultaneous ground-based measurements carried out at Zvenigorod (Moscow region, Russia). In a number of cases, the satellite data are significantly greater in value than the ground-based data. For the first half of 1996, the mean difference between the GOME data and the half-sum of the sunset and sunrise ground-based data amounts to about 33%. The accuracy of the satellite measurements performed in 1998 is found to be significantly higher than that in 1996, which appears to be associated with the improvement of the GOME data processing technique.