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1904133 
Journal Article 
Characterization of Odin-OSIRIS ozone profiles with the SAGE II dataset 
Adams, C; Bourassa, AE; Bathgate, AF; Mclinden, CA; Lloyd, ND; Roth, CZ; Llewellyn, EJ; Zawodny, JM; Flittner, DE; Manney, GL; Daffer, WH; Degenstein, DA 
2013 
Yes 
Atmospheric Measurement Techniques
ISSN: 1867-1381
EISSN: 1867-8548 
6 
5 
1447-1459 
WOS:000321679200023 
The Optical Spectrograph and Infra Red Imaging System (OS IRIS) on board the Odin spacecraft has been taking limb-scattered measurements of ozone number density profiles from 2001-present. The Stratospheric Aerosol and Gas Experiment II (SAGE II) took solar occultation measurements of ozone number densities from 1984-2005 and has been used in many studies of long-term ozone trends. We present the characterization of OSIRIS SaslcMART v5.0 x against the new SAGE II v7.00 ozone profiles for 2001-2005, the period over which these two missions had overlap. This information can be used to merge OSIRIS with SAGE II into a single ozone record from 1984 to the present, if other satellite ozone measurements are included to account for gaps in the OSIRIS dataset in the winter hemisphere. Coincident measurement pairs were selected for +/- 1 h, +/- 1 degrees latitude, and +/- 500 km. The absolute value of the resulting mean relative difference profile is <5 % for 13.5-54.5 km and <3 % for 24.5-53.5 km. Correlation coefficients R > 0.9 were calculated for 13.5-49.5 km, demonstrating excellent overall agreement between the two datasets. Coincidence criteria were relaxed to maximize the number of measurement pairs and the conditions under which measurements were taken. With the broad coincidence criteria, good agreement (<5 %) was observed under most conditions for 20.5-40.5 km. However, mean relative differences do exceed 5 % for several cases. Above 50 km, differences between OSIRIS and SAGE II are partly attributed to the diurnal variation of ozone. OSIRIS data are biased high compared with SAGE II at 22.5 km, particularly at high latitudes. Dynamical coincidence criteria, using derived meteorological products, were also tested and yielded similar overall results, with slight improvements to the correlation at high latitudes. The OSIRIS optics temperature is low (< 16 degrees C) during May-July, when the satellite enters the Earth's shadow for part of its orbit. During this period, OSIRIS measurements are biased low by 5-12 % for 27.5-38.5 km. Biases between OSIRIS ascending node (northward equatorial crossing time similar to 18:00 LT local time) and descending node (southward equatorial crossing time similar to 06:00 LT) measurements are also noted under some conditions. This work demonstrates that OSIRIS and SAGE II have excellent overall agreement and characterizes the biases between these datasets.