In:
Journal of Geophysical Research: Atmospheres, American Geophysical Union (AGU), Vol. 108, No. D7 ( 2003-04-16)
Abstract:
Vertical profiles of nitrogen dioxide in the 19–40 km altitude range are successfully retrieved over the globe from Optical Spectrograph and Infrared Imager System (OSIRIS) limb scatter observations in late 2001 and early 2002. The inclusion of multiple scattering in the radiative transfer model used in the inversion algorithm allows for the retrieval of NO 2 down to 19 km. The slant column densities, which represent the observations in the inversion, are obtained by fitting the fine structure in normalized radiance spectra over the 435–449 nm range, where NO 2 electronic absorption is readily observable because of long light paths through stratospheric layers rich in this constituent. Details of the spectral fitting and inversion algorithm are discussed, including the discovery of a pseudo‐absorber associated with pixelated detectors and a new method to verify altitude registration. Comparisons are made with spatially and temporally coincident profile measurements of this photochemically active trace gas. Better than 20% agreement is obtained with all correlative measurements over the common retrieval altitude range, confirming the validity of OSIRIS NO 2 profiles. Systematic biases in the number densities are not observed at any altitude. A “snapshot” meridional cross section between 40°N and 70°S is shown from observations during a fraction of an orbit.
Type of Medium:
Online Resource
ISSN:
0148-0227
DOI:
10.1029/2002JD002672
Language:
English
Publisher:
American Geophysical Union (AGU)
Publication Date:
2003
detail.hit.zdb_id:
161666-3
SSG:
16,13