Comparison of GOME-2/MetOp total ozone data with Brewer spectroradiometer data over the Iberian Peninsula
The main objective of this article is to compare the total ozone data from the new Global Ozone Monitoring Experiment instrument (GOME-2/MetOp) with reliable ground-based measurement recorded by five Brewer spectroradiometers in the Iberian Peninsula. In addition, a similar comparison for the pr...
Main Authors: | , , , , , , |
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Format: | Article |
Language: | English |
Published: |
Copernicus Publications
2009-04-01
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Series: | Annales Geophysicae |
Online Access: | https://www.ann-geophys.net/27/1377/2009/angeo-27-1377-2009.pdf |
Summary: | The main objective of this article is to compare the total ozone data from
the new Global Ozone Monitoring Experiment instrument (GOME-2/MetOp) with
reliable ground-based measurement recorded by five Brewer spectroradiometers
in the Iberian Peninsula. In addition, a similar comparison for the
predecessor instrument GOME/ERS-2 is described. The period of study is a
whole year from May 2007 to April 2008. The results show that GOME-2/MetOp
ozone data already has a very good quality, total ozone columns are on
average 3.05% lower than Brewer measurements. This underestimation is
higher than that obtained for GOME/ERS-2 (1.46%). However, the relative
differences between GOME-2/MetOp and Brewer measurements show significantly
lower variability than the differences between GOME/ERS-2 and Brewer data.
Dependencies of these relative differences with respect to the satellite
solar zenith angle (SZA), the satellite scan angle, the satellite cloud
cover fraction (CF), and the ground-based total ozone measurements are
analyzed. For both GOME instruments, differences show no significant
dependence on SZA. However, GOME-2/MetOp data show a significant dependence
on the satellite scan angle (+1.5%). In addition, GOME/ERS-2 differences
present a clear dependence with respect to the CF and ground-based total
ozone; such differences are minimized for GOME-2/MetOp. The comparison
between the daily total ozone values provided by both GOME instruments shows
that GOME-2/MetOp ozone data are on average 1.46% lower than GOME/ERS-2
data without any seasonal dependence. Finally, deviations of a priori climatological
ozone profile used by the satellite retrieval algorithm from the true ozone
profile are analyzed. Although excellent agreement between a priori climatological
and measured partial ozone values is found for the middle and high
stratosphere, relative differences greater than 15% are common for the
troposphere and lower stratosphere. |
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ISSN: | 0992-7689 1432-0576 |