Optical constants of ice from the ultraviolet to the microwave: A revised compilation

[1] A compilation of the spectral absorption coefficient of ice Ih is presented for temperatures near the melting point, superseding the compilation of Warren ( 1984). Significant changes are made to nearly all spectral regions. The blue and near- ultraviolet absorption is much weaker than the prior estimates, which were already very small. The near- infrared absorption coefficient differs by as much as a factor of 2 from the prior compilation at some wavelengths. The midinfrared absorption coefficient is rather uncertain in the weakly absorbing regions near 9 and 20 mm. New far- infrared measurements at low temperatures are extrapolated to higher temperatures, which shifts the peak positions. New microwave measurements find absorption much weaker than previously reported, by factors of 2 - 5. The real part of the index of refraction is computed using Kramers- Kronig analysis; it differs from the prior compilation only in the far infrared. Tables of the revised optical constants are available on a website.