Merged ozone profiles from four MIPAS processors
The Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) was an infrared (IR) limb emission spectrometer on the Envisat platform. Currently, there are four MIPAS ozone data products, including the operational Level-2 ozone product processed at ESA, with the scientific prototype processo...
| Main Authors: | , , , , , , , , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2017-04-01
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| Series: | Atmospheric Measurement Techniques |
| Online Access: | http://www.atmos-meas-tech.net/10/1511/2017/amt-10-1511-2017.pdf |
| _version_ | 1818367004730458112 |
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| author | A. Laeng T. von Clarmann G. Stiller B. M. Dinelli A. Dudhia P. Raspollini N. Glatthor U. Grabowski V. Sofieva L. Froidevaux K. A. Walker C. Zehner |
| author_facet | A. Laeng T. von Clarmann G. Stiller B. M. Dinelli A. Dudhia P. Raspollini N. Glatthor U. Grabowski V. Sofieva L. Froidevaux K. A. Walker C. Zehner |
| author_sort | A. Laeng |
| collection | DOAJ |
| description | The Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) was an
infrared (IR) limb emission spectrometer on the Envisat platform. Currently,
there are four MIPAS ozone data products, including the operational Level-2
ozone product processed at ESA, with the scientific prototype processor being
operated at IFAC Florence, and three independent research products developed
by the Istituto di Fisica Applicata Nello Carrara (ISAC-CNR)/University of Bologna, Oxford University, and the
Karlsruhe Institute of Technology–Institute of Meteorology and Climate
Research/Instituto de Astrofísica de Andalucía (KIT–IMK/IAA). Here we present a dataset of ozone vertical profiles obtained by
merging ozone retrievals from four independent Level-2 MIPAS processors. We
also discuss the advantages and the shortcomings of this merged product. As
the four processors retrieve ozone in different parts of the spectra
(microwindows), the source measurements can be considered as nearly
independent with respect to measurement noise. Hence, the information content
of the merged product is greater and the precision is better than those of
any parent (source) dataset.
<br><br>
The merging is performed on a profile per profile basis. Parent ozone
profiles are weighted based on the corresponding error covariance matrices;
the error correlations between different profile levels are taken into
account. The intercorrelations between the processors' errors are evaluated
statistically and are used in the merging. The height range of the merged
product is 20–55 km, and error covariance matrices are provided as
diagnostics. Validation of the merged dataset is performed by comparison with
ozone profiles from ACE-FTS (Atmospheric Chemistry Experiment–Fourier
Transform Spectrometer) and MLS (Microwave Limb
Sounder). Even though the merging is not supposed to remove the biases of
the parent datasets, around the ozone volume mixing ratio peak the merged
product is found to have a smaller (up to 0.1 ppmv) bias with respect to
ACE-FTS than any of the parent datasets. The bias with respect to MLS is of
the order of 0.15 ppmv at 20–30 km height and up to 0.45 ppmv at larger
altitudes. The agreement between the merged data MIPAS dataset with ACE-FTS
is better than that with MLS. This is, however, the case for all parent
processors as well. |
| first_indexed | 2024-12-13T22:45:10Z |
| format | Article |
| id | doaj.art-5321c0dbdb3940eb87503c5b71bcede7 |
| institution | Directory Open Access Journal |
| issn | 1867-1381 1867-8548 |
| language | English |
| last_indexed | 2024-12-13T22:45:10Z |
| publishDate | 2017-04-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Atmospheric Measurement Techniques |
| spelling | doaj.art-5321c0dbdb3940eb87503c5b71bcede72022-12-21T23:28:44ZengCopernicus PublicationsAtmospheric Measurement Techniques1867-13811867-85482017-04-011041511151810.5194/amt-10-1511-2017Merged ozone profiles from four MIPAS processorsA. Laeng0T. von Clarmann1G. Stiller2B. M. Dinelli3A. Dudhia4P. Raspollini5N. Glatthor6U. Grabowski7V. Sofieva8L. Froidevaux9K. A. Walker10C. Zehner11Institut für Meteorologie und Klimaforschung, Karlsruhe Institute of Technology, Karlsruhe, GermanyInstitut für Meteorologie und Klimaforschung, Karlsruhe Institute of Technology, Karlsruhe, GermanyInstitut für Meteorologie und Klimaforschung, Karlsruhe Institute of Technology, Karlsruhe, GermanyISAC-CNR, Bologna, ItalyEarth Observation Data Group, Oxford University, Oxford, UKIFAC-CNR, Florence, ItalyInstitut für Meteorologie und Klimaforschung, Karlsruhe Institute of Technology, Karlsruhe, GermanyInstitut für Meteorologie und Klimaforschung, Karlsruhe Institute of Technology, Karlsruhe, GermanyFinnish Meteorological Institute, Helsinki, FinlandJet Propulsion Laboratory, California Institute of Technology, Pasadena, USAUniversity of Toronto, Toronto, CanadaESA ESRIN, Frascati, ItalyThe Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) was an infrared (IR) limb emission spectrometer on the Envisat platform. Currently, there are four MIPAS ozone data products, including the operational Level-2 ozone product processed at ESA, with the scientific prototype processor being operated at IFAC Florence, and three independent research products developed by the Istituto di Fisica Applicata Nello Carrara (ISAC-CNR)/University of Bologna, Oxford University, and the Karlsruhe Institute of Technology–Institute of Meteorology and Climate Research/Instituto de Astrofísica de Andalucía (KIT–IMK/IAA). Here we present a dataset of ozone vertical profiles obtained by merging ozone retrievals from four independent Level-2 MIPAS processors. We also discuss the advantages and the shortcomings of this merged product. As the four processors retrieve ozone in different parts of the spectra (microwindows), the source measurements can be considered as nearly independent with respect to measurement noise. Hence, the information content of the merged product is greater and the precision is better than those of any parent (source) dataset. <br><br> The merging is performed on a profile per profile basis. Parent ozone profiles are weighted based on the corresponding error covariance matrices; the error correlations between different profile levels are taken into account. The intercorrelations between the processors' errors are evaluated statistically and are used in the merging. The height range of the merged product is 20–55 km, and error covariance matrices are provided as diagnostics. Validation of the merged dataset is performed by comparison with ozone profiles from ACE-FTS (Atmospheric Chemistry Experiment–Fourier Transform Spectrometer) and MLS (Microwave Limb Sounder). Even though the merging is not supposed to remove the biases of the parent datasets, around the ozone volume mixing ratio peak the merged product is found to have a smaller (up to 0.1 ppmv) bias with respect to ACE-FTS than any of the parent datasets. The bias with respect to MLS is of the order of 0.15 ppmv at 20–30 km height and up to 0.45 ppmv at larger altitudes. The agreement between the merged data MIPAS dataset with ACE-FTS is better than that with MLS. This is, however, the case for all parent processors as well.http://www.atmos-meas-tech.net/10/1511/2017/amt-10-1511-2017.pdf |
| spellingShingle | A. Laeng T. von Clarmann G. Stiller B. M. Dinelli A. Dudhia P. Raspollini N. Glatthor U. Grabowski V. Sofieva L. Froidevaux K. A. Walker C. Zehner Merged ozone profiles from four MIPAS processors Atmospheric Measurement Techniques |
| title | Merged ozone profiles from four MIPAS processors |
| title_full | Merged ozone profiles from four MIPAS processors |
| title_fullStr | Merged ozone profiles from four MIPAS processors |
| title_full_unstemmed | Merged ozone profiles from four MIPAS processors |
| title_short | Merged ozone profiles from four MIPAS processors |
| title_sort | merged ozone profiles from four mipas processors |
| url | http://www.atmos-meas-tech.net/10/1511/2017/amt-10-1511-2017.pdf |
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