| 1. |
- Brohede, Samuel, 1977, et al.
(författare)
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Validation of Odin/OSIRIS stratospheric NO2 profiles
- 2007
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Ingår i: Journal of Geophysical Research. - 0148-0227 .- 2156-2202. ; 112:D07310
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Tidskriftsartikel (refereegranskat)abstract
- This paper presents the validation study of stratospheric NO2 profiles retrieved from Odin/OSIRIS measurements of limb-scattered sunlight (version 2.4). The Optical Spectrograph and Infrared Imager System (OSIRIS) NO2 data set is compared to coincident solar occultation measurements by the Halogen Occultation Experiment (HALOE), Stratospheric Aerosol and Gas Experiment (SAGE) II, SAGE III, and Polar Ozone and Aerosol Measurement (POAM) III during the 2002–2004 period. Comparisons with seven Systeme d'Analyse par Observation Zenithal (SAOZ) balloon measurements are also presented. All comparisons show good agreement, with differences, both random and systematic, of less than 20% between 25 km and 35 km. Inconsistencies with SAGE III below 25 km are found to be caused primarily by diurnal effects from varying NO2 concentrations along the SAGE III line-of-sight. On the basis of the differences, the OSIRIS random uncertainty is estimated to be 16% between 15 km and 25 km, 6% between 25 km and 35 km, and 9% between 35 km and 40 km. The estimated systematic uncertainty is about 22% between 15 and 25 km, 11–21% between 25 km and 35 km, and 11–31% between 35 km and 40 km. The uncertainties for AM (sunrise) profiles are generally largest and systematic deviations are found to be larger at equatorial latitudes. The results of this validation study show that the OSIRIS NO2 profiles are well behaved, with reasonable uncertainty estimates between 15 km and 40 km. This unique NO2 data set, with more than hemispheric coverage and high vertical resolution will be of particular interest for studies of nitrogen chemistry in the middle atmosphere, which is closely linked to ozone depletion.
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| 2. |
- Kuttippurath, J., et al.
(författare)
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Intercomparison of ozone profile measurements from ASUR, SCIAMACHY, MIPAS, OSIRIS, and SMR
- 2007
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Ingår i: Journal of Geophysical Research. - 0148-0227 .- 2156-2202. ; 112:D9
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Tidskriftsartikel (refereegranskat)abstract
- The airborne submillimeter radiometer ( ASUR) was deployed onboard the Falcon research aircraft during the scanning imaging absorption spectrometer for atmospheric cartography ( SCIAMACHY) validation and utilization experiment ( SCIAVALUE) and the European polar stratospheric cloud and lee wave experiment ( EuPLEx) campaigns. A large number of ozone profile measurements were performed over a latitude band spanning from 5 degrees S to 80 degrees N in September 2002 and February/March 2003 during the SCIAVALUE and around the northern polar latitudes in January/February 2003 during the EuPLEx. Both missions amassed an ample microwave ozone profile data set that is used to make quantitative comparisons with satellite measurements in order to assess the quality of the satellite retrievals. In this paper, the ASUR ozone profile measurements are compared with measurements from SCIAMACHY and Michelson interferometer for passive atmospheric sounding ( MIPAS) on Environmental Satellite and optical spectrograph and infrared imager system ( OSIRIS) and submillimeter radiometer ( SMR) on the Odin satellite. The cross comparisons with the criterion that the ASUR measurements are performed within +/- 1000 km and +/- 6 hrs of the satellite observations show a good agreement with all the four satellite sensors. The differences in data values are the following: -4 to +8% for ASUR-SCIAMACHY ( operational product, v2.1), within +/- 15% for ASUR-SCIAMACHY ( scientific product, v1.62), up to +6% for ASUR-MIPAS ( operational product v4.61) and ASUR- MIPAS ( scientific product v1-O(3)-1), up to 17% for ASUR- OSIRIS ( v012), and -6 to 17% for ASUR- SMR ( v222) between the 20- and 40- km altitude range depending on latitude. Thus, the intercomparisons provide important quantitative information about the quality of the satellite ozone profiles, which has to be considered when using the data for scientific analyses.
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