Abstract

Distributions of stratospheric water vapor from the Nimbus 7 LIMS experiment have been reported in the literature (WMO, 1986; Russell, 1987; Remsberg et al., 1989) and used for scientific study (e.g. Jones et al., 1986; Hansen and Robinson, 1989). In general, the picture that has emerged is consistent with the mechanisms believed to be controlling water vapor there--namely, the transport of near-saturated air upward through the tropical tropopause and then poleward, plus the process of "methane oxidation," which produces water vapor primarily in the upper stratosphere. Russell et al. (1984) and Remsberg et al. (1984) previously reviewed both the theoretical estimates of error as well as differences with in situ measurements of water vapor obtained at approximately the same time and location as a LIMS measurement. Their reported estimated accuracy of the LIMS water vapor data for single profiles is of the order of 20 percent from 30 to 3 mb over most regions, decreasing to 30 percent at 1 mb and 38 percent at 70 mb. Systematic errors associated with uncertainties in the absorption cross sections near 6.9 μm for H₂O, CH₄, and O₂ are updated in this paper based on improvements that have been made available since the LIMS data were processed.

© 1990 Optical Society of America