Stratospheric NO 2 and H 2 O mixing ratio profiles from high resolution infrared solar spectra using nonlinear least squares

Nonlinear least squares spectral curve fitting has been used to derive vertical mixing ratio profiles for NO 2 and H 2 O above 16 km from high resolution (∼.02 cm −1 ) solar spectra collected during sunset with a balloon borne interferometer. The NO 2 profile shows a sharp peak of ˜8 ppbv at 32 km falling rapidly to <0.5 ppbv at 17 km. The H 2 O profile shows a broad peak of ˜6.5 ppmv at 30 km falling to <4 ppmv at 17 km.