The column-averaged volume mixing ratio (VMR) of CO2 over Kitt Peak, Arizona, has been retrieved from high-resolution solar absorption spectra obtained with the Fourier transform spectrometer on the McMath telescope. Simultaneous column measurements of CO2 at ~6300 cm-1 and O2 at ~7900 cm-1 were ratioed to minimize systematic errors. These column ratios were then scaled by the mean O2 VMR (0.2095) to yield column-averaged vmrs of CO2. These display similar behavior to the Mauna Loa in situ surface measurements. During the period 1977--1995, the column-averaged mixing ratio of CO2 increased at an average rate of 1.49 ¿ 0.04 ppmv/yr with seasonal variations of ~7 ppmv peak-to-peak. Our retrievals demonstrate that this remote technique is capable of precisions better than 0.5%.