Temperature dependence of light absorption by water

A model is described that relates the temperature coefficient of the optical absorption spectrum of pure water to the frequency derivative of that spectrum and two parameters that quantify the dependence of a peak's amplitude and its position on temperature. When applied to experimental temperature coefficients, it provides a better understanding of the process than the analysis currently in use.

► We propose a model for the temperature dependence (TD) of optical absorption by water.
► TD separated into contributions from intensity change and frequency shift.
► Experimental data indicate frequency shift is positive.
► Peaks predicted to have positive TD on high frequency side, negative on low.
► Model provides improved understanding of experiments.