In:
Earth System Science Data, Copernicus GmbH, Vol. 13, No. 1 ( 2021-01-29), p. 199-211
Abstract:
Abstract. Measurements of atmospheric column-averaged dry-air mole fractions of carbon dioxide
(XCO2), methane (XCH4), and carbon monoxide (XCO) have been collected
across the Pacific Ocean during the Measuring Ocean REferences 2 (MORE-2) campaign in June
2019. We deployed a shipborne variant of the EM27/SUN Fourier transform spectrometer (FTS) on
board the German R/V Sonne which, during MORE-2, crossed the Pacific Ocean
from Vancouver, Canada, to Singapore. Equipped with a specially manufactured fast solar tracker,
the FTS operated in direct-sun viewing geometry during the ship cruise reliably delivering solar
absorption spectra in the shortwave infrared spectral range (4000 to 11000 cm−1). After
filtering and bias correcting the dataset, we report on XCO2, XCH4, and
XCO measurements for 22 d along a trajectory that largely aligns with 30∘ N of
latitude between 140∘ W and 120∘ E of longitude. The dataset has been scaled to the
Total Carbon Column Observing Network (TCCON) station in Karlsruhe, Germany, before and after the
MORE-2 campaign through side-by-side measurements. The 1σ repeatability of hourly means of
XCO2, XCH4, and XCO is found to be 0.24 ppm, 1.1 ppb, and
0.75 ppb, respectively. The Copernicus Atmosphere Monitoring Service (CAMS) models
gridded concentration fields of the atmospheric composition using assimilated satellite
observations, which show excellent agreement of 0.52±0.31 ppm for XCO2,
0.9±4.1 ppb for XCH4, and 3.2±3.4 ppb for XCO (mean
difference ± SD, standard deviation, of differences for entire record) with our
observations. Likewise, we find excellent agreement to within 2.2±6.6 ppb with the
XCO observations of the TROPOspheric MOnitoring Instrument (TROPOMI) on the Sentinel-5
Precursor satellite (S5P). The shipborne measurements are accessible at
https://doi.org/10.1594/PANGAEA.917240 (Knapp et al., 2020).
Type of Medium:
Online Resource
ISSN:
1866-3516
DOI:
10.5194/essd-13-199-2021
Language:
English
Publisher:
Copernicus GmbH
Publication Date:
2021
detail.hit.zdb_id:
2475469-9
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