Mid-latitude ozone monitoring with the GOMOS-ENVISAT experiment version 5: the noise issue

Abstract : The GOMOS ozone profiles have been analysed to evaluate the GOMOS ability to capture the long-term ozone evolution at mid-latitudes during the expected recovery phase of the ozone layer. Version 5 of the operational GOMOS ozone data has been compared with data from two of the longest ground-based instruments based on different techniques and already involved with many other previous space instrument validations. Comparisons between ground-based and GOMOS data confirm the occurrence of spurious retrievals mainly occurring since 2006. Using a selected set of data it is shown that some bad retrievals are induced by the increasing dark charge of the detectors combined with an inadequate method for its correction. This effect does not only induce a continuous bias, but is rather exhibiting a bimodal distribution including the correct profiles and the bad retrievals. For long-term analyses it is recommended filtering the data according to background light conditions and star temperature (spectrum shape). The new method of the dark charge estimate proposed to be implemented in the version 6 of the ESA algorithm seems to significantly reduce the occurrence of such effects and should allow to monitor stratospheric ozone using GOMOS data with greater confidence.
Complete list of metadatas

Cited literature [33 references]  Display  Hide  Download

https://hal.archives-ouvertes.fr/hal-00492563
Contributor : Catherine Cardon <>
Submitted on : Friday, January 1, 2016 - 5:36:45 PM
Last modification on : Wednesday, May 15, 2019 - 3:49:53 AM
Long-term archiving on : Thursday, April 7, 2016 - 5:03:02 PM

File

acp-10-11839-2010.pdf
Publisher files allowed on an open archive

Identifiers

Citation

Philippe Keckhut, Alain Hauchecorne, Laurent Blanot, K. Hocke, Sophie Godin-Beekmann, et al.. Mid-latitude ozone monitoring with the GOMOS-ENVISAT experiment version 5: the noise issue. Atmospheric Chemistry and Physics, European Geosciences Union, 2010, 10 (23), pp.11839-11849. ⟨10.5194/acp-10-11839-2010⟩. ⟨hal-00492563⟩

Share

Metrics

Record views

313

Files downloads

186