Toptygin, A.Y., K.G. Gribanov, V.I. Zakharov, Y. Kasai, A. Kagawa, Y. Murayama, R. Imasu, G. Schmidt, G. Hoffmann, and J. Jouzel, 2007: Determination of vertical HDO / H2O profile from high -
resolution atmospheric transmission spectra.
There were lots of studies of
atmospheric transmission (and hence aerosol optical depth) starting with the work of Marvin and later Hand of the National Weather Service.