Retrieval of trace gas profiles from a low-resolution emission radiometer flown on the MANTRA 2002 balloon mission

Results are presented for an infrared emission radiometer that was flown on the MANTRA 2002 balloon mission. The balloon was launched at 08:02 UTC on September 3, 2002 from Vanscoy, Canada (52^oN, 107^oW). Raw radiance measurements collected during the balloon ascent are analyzed using a forward estimation technique to simultaneously recover multiple trace gas profiles from the low-resolution spectral measurements of atmospheric radiance. The technique uses detailed atmosphere and instrument models and a least-mean-squares simplex estimator to iterate best-fit volume mixing ratios for several gas species, based on atmospheric emission data taken in the 800--1250 cm^-1 atmospheric window at an instrument resolution of 20 cm^-1. Retrieved vertical mixing ratio profiles for ozone and nitric acid are compared with those derived from ozonesondes and infrared solar occultation spectra recorded by a high-resolution Fourier transform spectrometer during the same balloon flight. They are also compared with available overpass data from the SCIAMACHY and MIPAS instruments onboard the ENVISAT platform.