Spectrometric measurements of column NO2 abundances with a zenith viewing spectrometer working in 435-450 nm wavelength range, and a special numerical technique are used to retrieve NO2 vertical distribution in the stratosphere and to estimate the level of tropospheric NO2 contaminations. We present: 1) results of systematic NO2 measurements at Zvenigorod Scientific Station since 1990, and 2) meridional distribution of NO2 in the Atlantic Ocean measured from a ship in November 1989. The low- tropospheric NO2 contents at Zvenigorod during pollution episodes can considerably exceed stratospheric columnar contents. Stratospheric NO2 decreases dramatically in 1992, after the Mt. Pinatubo eruption, just in the volcanic aerosol layer. Measurements of NO2 in the Atlantic Ocean reveal the latitudinal structure of stratospheric NO2; tropospheric NO2 contents are usually negligible but reach significant values when the ship approaches continents or intensive sea roads.