Remote measurement of surface pressure using absorption in the oxygen A-band

A simple technique is described that measures the atmospheric absorption in the oxygen A-band near 0.76 microns. A narrow interference filter is tilted so that its passband scans through the two branches of the absorption band. By viewing the direct solar beam a differential absorption measurement of the mass of oxygen in the optical path is obtained which is then compared to surface pressure. A transmittance model is described which gives results that agree well with the measurements. The model is also used to investigate the possible extension of the technique to a satellite-borne instrument for estimating surface pressure.