In situ ship and aircraft observation-based column-averaged mixing ratios of CO2 (obs. XCO2) over the Western Pacific Ocean

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The dataset contains the timeseries of monthly "observation-based XCO2" (obs. XCO2) over the Western Pacific Ocean from 2014 to 2016 for three representative latitude ranges: the northern midlatitudes (20–30° N), the Equator region (0–10° N), and southern latitudes (20–10° S). The dataset was obtained by integrating cargo-ship and commercial aircraft observations with the aid of state-of-the art atmospheric chemistry-transport model calculations.
The spatial and temporal coverage of the dataset will be continously extended and updated.


Release date
Temporal coverage
2014/01/01 - 2016/12/31
Data provider
Email: cgerdb_admin(at)
File format
Data volume
10 KB
ver.1.0 (Last updated: 2022/08/05)

Data Set

Column-averaged mixing ratios of CO2
Details of 3 domains
[Region 1] lat: 20–30°N, lon: 130-150°E
[Region 2] lat: 0-10°N, lon: 140-160°E
[Region 3] lat: 20-10°S, lon: 145-165°E
Time resolution
1 month
Spatial resolution
  Latitude: 10 degrees, Longitude: 20 degrees
Calculation method
In-situ CO2 observations onboard cargo-ships of the Ship Of Opportunity program (SOOP, ) and onboard commercial aircrafts of the Comprehensive Observation Network for Trace gases by Airliner (CONTRAIL, are monthly averaged within 10° latitude by 20° longitude boxes over the ocean. The monthly averages are integrated with the aid of state-of-the art atmospheric chemistry-transport model calculations to obtain observation-based CO2 profiles. Using equation (15) of Connor et al. (2008) (, and parameters of GOSAT (Greenhouse Gases Observing Satellite) retrievals, an "observation-based column-averaged CO2" (obs. XCO2) dataset is calculated (
[Free keywords]
    Carbon cycle, Climate change, Greenhouse gas, Satellite Validation
    Water-based Platforms > Vessels > Surface > Ships
    Air-based Platforms > Jet > Airplane
    Space-based Platforms > Earth Observation Satellites > GOSAT
Update history
     Data are released. ver.1.0.

References Information

Müller, A., Tanimoto, H., Sugita, T., Machida, T., Nakaoka, S., Patra, P. K., Laughner, J., and Crisp, D.(2020): New approach to evaluate satellite derived XCO2 over oceans by integrating ship and aircraft observations, Atmos. Chem. Phys., doi:10.5194/acp-21-8255-2021.

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The User may re-distribute the data to third party without any change or transformation of the data, and may publish new intellectual products (hereafter "Products") based on this data set.
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When publishing any Products based on the present data set, it must be clearly stated that the present data set was used.
However, the Author may request the User to delete the citation from the Product. In that case, the User shall comply with the request within reasonable extent.
Citation format

When this data set is referred to in publications, it should be cited in the following format.
  Astrid Müller (2022), In situ ship and aircraft observation-based column-averaged
  mixing ratios of CO2 (obs. XCO2) over the Western Pacific Ocean, ver.x.x*1, NIES,
  DOI:10.17595/20220805.001. (Reference date*2: YYYY/MM/DD)
  *1 The version number is indicated in the name of each data file.
  *2 As the reference date, please indicate the date you downloaded the files.

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Re-distribution of the data or release of Products derived from the data set, shall be reported to the Data Provider without delay.
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