Atmospheric Emitted Radiance Interferometer Part II: Water Vapor and Atmospheric Aerosols

Atmospheric Emitted Radiance Interferometer (AERI) spectra provide detailed characterization of the infrared component of the surface radiation budget (Ellingson et al. 1995), support spectroscopic (Clough et al. 1989; Revercomb et al. 1995) and cloud (Smith et al. 1992; Collard et al. 1995) radiative modeling studies for improving radiative transfer calculations, and are the basis for high time-resolution remote sensing of atmospheric state parameters (Feltz et al. 1996). Here we focus on the quantification of sources of opacity in the clear sky window region, one of the key spectroscopic issues for accurate surface energy budget modeling. Three important contributors to uncertainty in the window region opacity that are somewhat difficult to separate are 1) water vapor continuum, 2) aerosols, and 3) atmospheric water vapor profile. We present progress in investigations of the latter two contributors, which we expect will ultimately lead to refinements in the water vapor continuum. New information has better defined the uncertainties of atmospheric water vapor observations, and approaches for reducing these uncertainties are being formulated and tested.