Seasonal cycles of carbon monoxide over the Arctic and Antarctic: total columns versus surface data

Mixing ratios of carbon monoxide, averaged over the total atmospheric thickness, were measured in the Arctic and in the Antarctic by a solar spectroscopic technique and compared with surface concentrations. Early spring values of total column average concentration turned out to be lower than those near the surface in the Arctic and higher in the Antarctic. In summer the values, measured by these two different modes, were close to one another. This phenomenon could be explained by incomplete vertical mixing in the polar regions during winter-spring time as well as by different locations of CO sources and transport patterns in the two hemispheres. These results illustrate advantages of a combination of surface based in-situ and total column measurements at the same place.