We have previously demonstrated a pulsed direct detection IPDA lidar to measure range and the column concentration of atmospheric CO₂. The lidar measures the atmospheric backscatter profiles and samples the shape of the 1,572.33 nm CO₂ absorption line. We participated in the ASCENDS science flights on the NASA DC-8 aircraft during August 2011 and report here lidar measurements made on four flights over a variety of surface and cloud conditions near the US. These included over a stratus cloud deck over the Pacific Ocean, to a dry lake bed surrounded by mountains in Nevada, to a desert area with a coal-fired power plant, and from the Rocky Mountains to Iowa, with segments with both cumulus and cirrus clouds. Most flights were to altitudes >12 km and had 5–6 altitude steps. Analyses show the retrievals of lidar range, CO₂ column absorption, and CO₂ mixing ratio worked well when measuring over topography with rapidly changing height and reflectivity, through thin clouds, between cumulus clouds, and to stratus cloud tops. The retrievals shows the decrease in column CO₂ due to growing vegetation when flying over Iowa cropland as well as a sudden increase in CO₂ concentration near a coal-fired power plant. For regions where the CO₂ concentration was relatively constant, the measured CO₂ absorption lineshape (averaged for 50 s) matched the predicted shapes to better than 1% RMS error. For 10 s averaging, the scatter in the retrievals was typically 2–3 ppm and was limited by the received signal photon count. Retrievals were made using atmospheric parameters from both an atmospheric model and from in situ temperature and pressure from the aircraft. The retrievals had no free parameters and did not use empirical adjustments, and >70% of the measurements passed screening and were used in analysis. The differences between the lidar-measured retrievals and in situ measured average CO₂ column concentrations were <1.4 ppm for flight measurement altitudes >6 km.