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<p>Measurements of atmospheric column-averaged dry-air mole fractions of carbon dioxide (<span class="inline-formula">XCO₂</span>), methane (<span class="inline-formula">XCH₄</span>), and carbon monoxide (<span class="inline-formula">XCO</span>) 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 <i>Sonne</i> 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 <span class="inline-formula">cm⁻¹</span>). After filtering and bias correcting the dataset, we report on <span class="inline-formula">XCO₂</span>, <span class="inline-formula">XCH₄</span>, and <span class="inline-formula">XCO</span> measurements for 22 d along a trajectory that largely aligns with 30<span class="inline-formula">^∘</span> N of latitude between 140<span class="inline-formula">^∘</span> W and 120<span class="inline-formula">^∘</span> 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 <span class="inline-formula">1<i>σ</i></span> repeatability of hourly means of <span class="inline-formula">XCO₂</span>, <span class="inline-formula">XCH₄</span>, and <span class="inline-formula">XCO</span> is found to be 0.24 <span class="inline-formula">ppm</span>, 1.1 <span class="inline-formula">ppb</span>, and 0.75 <span class="inline-formula">ppb</span>, respectively. The Copernicus Atmosphere Monitoring Service (CAMS) models gridded concentration fields of the atmospheric composition using assimilated satellite observations, which show excellent agreement of <span class="inline-formula">0.52±0.31</span> <span class="inline-formula">ppm</span> for <span class="inline-formula">XCO₂</span>, <span class="inline-formula">0.9±4.1</span> <span class="inline-formula">ppb</span> for <span class="inline-formula">XCH₄</span>, and <span class="inline-formula">3.2±3.4</span> <span class="inline-formula">ppb</span> for <span class="inline-formula">XCO</span> (mean difference <span class="inline-formula">±</span> SD, standard deviation, of differences for entire record) with our observations. Likewise, we find excellent agreement to within <span class="inline-formula">2.2±6.6</span> <span class="inline-formula">ppb</span> with the <span class="inline-formula">XCO</span> observations of the TROPOspheric MOnitoring Instrument (TROPOMI) on the Sentinel-5 Precursor satellite (S5P). The shipborne measurements are accessible at <a href="https://doi.org/10.1594/PANGAEA.917240">https://doi.org/10.1594/PANGAEA.917240</a> <span class="cit" id="xref_paren.1">(<a href="#bib1.bibx34">Knapp et al.</a>, <a href="#bib1.bibx34">2020</a>)</span>.</p>