EOS Validation Program

Institution: Jet Propulsion Laboratory
                    M. S. 183-601
                    4800 Oak Grove Drive
                    Pasadena, CA 91109-8099
Phone: (818) 354-2940
FAX: (818) 354-5148
E-mail: linda.r.brown@jpl.nasa.gov

R. A. Toth (JPL)
G. Toon (JPL)
B. Sen (JPL)
V. M. Devi (Collge of William & Mary)
D. C. Benner (College of William & Mary)

R. R. Gamache (U of Mass)
L. S. Rothman (Harvard-Smithsonian)
C. P. Rinsland (LARC)
L. L. Strow (U of Maryland)
D. Edwards (NCAR)

February 2003
April 2004
Final Report

This proposed laboratory study will update molecular line parameters of H2O, NO2, CH4 and CO in the HITRAN compilation for AIRS, TES and HIRDLS. We will evaluate available line positions, intensities and line shape parameters at room temperature for H2O and NO2 and combine them with our new proposed line shape measurements. The datasets will be placed into HITRAN format for water transitions between 600 and 2100 cm-1 and NO2 transitions between 1560 and 1660 cm-1. We will also merge ongoing measurements of line intensities and line shape parameters (obtained through other contracts) for CH4 transitions between 1000 and 3200 cm-1 and CO transitions of the 1 - 0 fundamental band near 2150 cm-1. The goal will be to incorporate accurate line shape parameters into the HITRAN database for EOS tropospheric retrievals of these four molecular species.

Our laboratory study will characterize the temperature dependence of air-broadened H2O and air-broadened NO2 line shape coefficients (widths and pressure-induced shifts in positions) for which there are scant measurements. For H2O, some 1000 air-broadened widths and shifts at temperatures between 300 and 450 K will be measured between 600 and 2100 cm-1 in laboratory spectra recorded with the FTS at Kitt Peak. For NO2, some 600 air- broadened widths and shifts will be measured at temperatures between 210 and 400 K. These data will be analyzed to form empirical lists of widths and shift coefficients as a function of rotational quantum numbers. These will be merged with published room temperature results for air- and self-broadened widths, line positions and intensities to obtain complete and accurate new compilations for H2O and NO2 in the spectral intervals critical to AIRS, TES and HIRDLS.