Stratospheric nitric oxide and ozone measurements using photoionization mass spectrometry and UV absorption

Observations of NO2 densities from 28 to 40 km as measured by the Solar Mesosphere Explorer (SME) satellite are compared to model calculations for the month of January. Low densities are obtained in the tropics and in high latitude winter, with much larger values in the summer middle and high latitude regions in both the observations and the model. The reasons for areas of agreement and disagreement between the model and the observations are explored. The observed NO2 distribution is also used to infer the N2O5 distribution based on presently accepted chemistry and suggests that very large amounts of N2O5 are present in high latitude winter.

Section: Results and Analysissupporting

confidence: 84%

Measurements of stratospheric NO₂ from the solar mesosphere explorer satellite: 2. General morphology of observed NO₂ and derived N₂O₅

Solomon¹,

Mount²,

Zawodny³

1984

“…At lower altitudes, data from this flight are comparatively low, especially around the measured minimum at 50 mbar. A similar strong gradient in the NO mixing ratio was also found by Maier et al [1978], though at higher altitudes. Drummond et al [1977] found a strong gradient at lower altitudes.…”

Section: No2 + No3 + M--> N205supporting

confidence: 78%

Stratospheric NO measurements: A new balloon‐borne chemiluminescent instrument

Weiler¹,

Fabian²,

Flentje³

et al. 1980

A description of a new chemiluminescent balloon sonde for measuring stratospheric nitric oxide is given. First results from three flights at mid‐latitudes are presented, including measurements showing a slow reduction in NO mixing ratio beginning 2½ hours before sunset. A hysteresis in the NO mixing ratio between ascent in the morning and descent in the afternoon was observed. The afternoon values were found to be up to a factor of 2 larger than the morning values.

“…We will report below on a program to measure simultaneously stratospheric total column abundances above 12 km of Ja The variability in the amounts of N20, NO, NO2, and HNO3 with respect to changing latitude, season, and solar input will be examined in turn. Figure 1 shows measured profiles of N20, NO, NO2, and HNO3 as reported by various investigators [Schutz et al, 1970;Goldman et al, 1973Goldman et al, , 1978Marries, 1973;Marries et al, 1974;Ehhalt et al, 1974;Lazrus and Ganø drud, 1974;Ridley et al, 1974Ridley et al, , 1975Ridley et al, , 1976Ackerman et al, 1975;Bloxam et al, 1975;Chaloner et al, 1975;Evans et al, 1975Evans et al, , 1976Fontanella et al, 1975;Schmeltekooef et al, 1975Schmeltekooef et al, , 1977Meidt et al, 1976;Kerr and McElroy, 1976;Drummond et al, 1977;Krey et al, 1977;Loewenstein et al, 1978a, b;Maier et al, 1978;Fedder et al, 1978]. While these profiles show var-iabilities that are due to both natural and instrumental sources, they do demonstrate the typical stratospheric vertical distribution characteristics of each species.…”

Section: Introductionmentioning

confidence: 77%

Simultaneous spectroscopic determination of the latitudinal, seasonal, and diurnal variability of stratospheric N₂O, NO, NO₂, and HNO₃

Coffey¹,

Mankin²,

Goldman³

1981

109

The importance Of NOx compounds to stratospheric chemistry has been clearly established. We report below on a program to measure latitudinal, seasonal, and diurnal variations in stratospheric N2O, NO, NO2, and HNO3 amounts. Through the use of airborne Fourier transform absorption spectroscopy, we determine simultaneously column amounts above 12 km of the four molecules listed above. Nitrous oxide (N2O) is found to have a fairly uniform distribution with latitude and season, with a stratospheric column abundance of 8.1 × 1017 molecules cm−2. Nitric oxide (NO) amounts are shown to decrease with increasing latitude in winter. A 50% decrease in high latitude winter amounts is observed as compared with low latitude values near 3.0 × 1015 molecules cm−2. Nitrogen dioxide (NO2) stratospheric amounts increase in summer with increasing latitude. Equatorial values are near 3.0 × 1015 molecules cm−2 above 12 km. A factor of 3–4 increase in higher latitude summertime NO2, as compared to winter NO2, is observed. Nitric acid (HNO3) amounts show a general increase toward higher latitudes and a marked increase in mid‐latitude winter as compared to summer. Winter amounts may be highly variable with a value near 1.0 × 1016 molecules cm−2.