Validation of OMI-TOMS and OMI-DOAS total ozone column using five Brewer spectroradiometers at the Iberian peninsula

Validation of OMI-TOMS and OMI-DOAS total ozone column using
five Brewer spectroradiometers at the Iberian peninsula
M. Anto´n,1 M. Lo´pez,2 J. M. Vilaplana,3 M. Kroon,4 R. McPeters,5 M. Ban˜o´n,2
and A. Serrano1
Received 4 March 2009; revised 6 May 2009; accepted 8 May 2009; published 28 July 2009.
[1] This article focuses on the comparison of the total ozone column data from the Ozone
Monitoring Instrument (OMI) flying aboard the NASA EOS-Aura satellite platform with
ground-based measurement recorded by Brewer spectroradiometers located at five
Spanish remote sensing ground stations between January 2005 and December 2007. The
satellite data are derived from two algorithms: OMI Total Ozone Mapping Spectrometer
(OMI-TOMS) and OMI Differential Optical Absorption Spectroscopy (OMI-DOAS).
The largest relative differences between these OMI total ozone column estimates reach 5%
with a significant seasonal dependence. The agreement between OMI ozone data and
Brewer measurements is excellent. Total ozone columns from OMI-TOMS are on average
a mere 2.0% lower than Brewer data. For OMI-DOAS data the bias is a mere 1.4%.
However, the relative difference between OMI-TOMS and Brewer measurements shows
a notably lower seasonal dependence and variability than the differences between
OMI-DOAS and ground-based data. For both OMI ozone data products these relative
differences show significant dependence on the satellite ground pixel solar zenith angle
for cloud-free cases as well as for cloudy conditions. However, the OMI ozone data
products are shown to reveal opposite behavior with respect to the two antagonistic
sky conditions. No significant dependency of the ground-based to satellite-based
differences with respect to the satellite cross-track position is seen for either OMI retrieval
algorithm.
Citation: Anto´n, M., M. Lo´pez, J. M. Vilaplana, M. Kroon, R. McPeters, M. Ban˜o´n, and A. Serrano (2009), Validation of
OMI-TOMS and OMI-DOAS total ozone column using five Brewer spectroradiometers at the Iberian peninsula, J. Geophys. Res., 114,
D14307, doi:10.1029/2009JD012003.