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<p>Accurate monitoring of atmospheric carbon dioxide (CO<span class="inline-formula">₂</span>) and its distribution is of great significance for studying the carbon cycle and predicting future climate change. Compared to the ground observational sites, the airborne observations cover a wider area and simultaneously observe a variety of surface types, which helps with effectively monitoring the distribution of CO<span class="inline-formula">₂</span> sources and sinks. In this work, an airborne experiment was carried out in March 2019 over the Shanhaiguan area, China (39–41<span class="inline-formula">^∘</span> N, 119–121<span class="inline-formula">^∘</span> E). An integrated path differential absorption (IPDA) light detection and ranging (lidar) system and a commercial instrument, the ultraportable greenhouse gas analyser (UGGA), were installed on an aircraft to observe the CO<span class="inline-formula">₂</span> distribution over various surface types. The pulse integration method (PIM) algorithm was used to calculate the differential absorption optical depth (DAOD) from the lidar data. The CO<span class="inline-formula">₂</span> column-averaged dry-air mixing ratio (XCO<span class="inline-formula">₂</span>) was calculated over different types of surfaces including mountain, ocean, and urban areas. The concentrations of the XCO<span class="inline-formula">₂</span> calculated from lidar measurements over ocean, mountain, and urban areas were 421.11 <span class="inline-formula">±</span> 1.24, 427.67 <span class="inline-formula">±</span> 0.58, and 432.04 <span class="inline-formula">±</span> 0.74 ppm, respectively. Moreover, through the detailed analysis of the data obtained from the UGGA, the influence of pollution levels on the CO<span class="inline-formula">₂</span> concentration was also studied. During the whole flight campaign, 18 March was the most heavily polluted day with an Air Quality Index (AQI) of 175 and PM<span class="inline-formula">_2.5</span> of 131 <span class="inline-formula">µ</span>g m<span class="inline-formula">⁻³</span>. The aerosol optical depth (AOD) reported by a sun photometer installed at the Funing ground station was 1.28. Compared to the other days, the CO<span class="inline-formula">₂</span> concentration measured by UGGA at different heights was the largest on 18 March with an average value of 422.59 <span class="inline-formula">±</span> 6.39 ppm, which was about 10 ppm higher than the measurements recorded on 16 March. Moreover, the vertical profiles of Orbiting Carbon Observatory-2 (OCO-2) and CarbonTracker were also compared with the aircraft measurements. All the datasets showed a similar variation with some differences in their CO<span class="inline-formula">₂</span> concentrations, which showing a good agreement among them.</p>