CH<sub>4</sub>, CO, and H<sub>2</sub>O spectroscopy for the Sentinel-5 Precursor mission: an assessment with the Total Carbon Column Observing Network measurements
release_t4qhgekf3zfsnilyw4vm6aet6u
by
A. Galli, A. Butz, R. A. Scheepmaker, O. Hasekamp, J. Landgraf, P. Tol, D. Wunch, N. M. Deutscher, G. C. Toon, P. O. Wennberg, D. W. T. Griffith, I. Aben
Abstract
<strong>Abstract.</strong> The TROPOspheric Monitoring Instrument (TROPOMI) will be part of ESA's Sentinel-5 Precursor (S5P) satellite platform scheduled for launch in 2015. TROPOMI will monitor methane and carbon monoxide concentrations in the Earth's atmosphere by measuring spectra of back-scattered sunlight in the short-wave infrared (SWIR). <br><br> S5P will be the first satellite mission to rely uniquely on the spectral window at 4190–4340 cm<sup>−1</sup> (2.3 μm) to retrieve CH<sub>4</sub> and CO. In this study, we investigated if the absorption features of the three relevant molecules CH<sub>4</sub>, CO, and H<sub>2</sub>O are adequately known. To this end, we retrieved total columns of CH<sub>4</sub>, CO, and H<sub>2</sub>O from absorption spectra measured by two ground-based Fourier transform spectrometers that are part of the Total Carbon Column Observing Network (TCCON). The retrieval results from the 4190–4340 cm<sup>−1</sup> range at the TROPOMI resolution (0.45 cm<sup>−1</sup>) were then compared to the CH<sub>4</sub> results obtained from the 6000 cm<sup>−1</sup> region, and the CO results obtained from the 4190–4340 cm<sup>−1</sup> region at the higher TCCON resolution (0.02 cm<sup>−1</sup>). <br><br> For TROPOMI-like settings, we were able to reproduce the CH<sub>4</sub> columns to an accuracy of 0.3% apart from a constant bias of 1%. The CO retrieval accuracy was, through interference, systematically influenced by the shortcomings of the CH<sub>4</sub> and H<sub>2</sub>O spectroscopy. In contrast to CH<sub>4</sub>, the CO column error also varied significantly with atmospheric H<sub>2</sub>O content. Unaddressed, this would introduce seasonal and latitudinal biases to the CO columns retrieved from TROPOMI measurements. We therefore recommend further effort from the spectroscopic community to be directed at the H<sub>2</sub>O and CH<sub>4</sub> spectroscopy in the 4190–4340 cm<sup>−1</sup> region.
In application/xml+jats
format
Archived Files and Locations
application/pdf 981.2 kB
file_jkrvbh4u7je7vbwcgvzzbcjkly
|
web.archive.org (webarchive) www.atmos-meas-tech.net (web) |
application/pdf 990.0 kB
file_mis5dztc75evhm755owpf6qxna
|
core.ac.uk (web) web.archive.org (webarchive) |
Open Access Publication
In DOAJ
In ISSN ROAD
In Keepers Registry
ISSN-L:
1867-1381
access all versions, variants, and formats of this works (eg, pre-prints)
Crossref Metadata (via API)
Worldcat
SHERPA/RoMEO (journal policies)
wikidata.org
CORE.ac.uk
Semantic Scholar
Google Scholar