Improving IR cloud phase determination with 20 microns spectral observations

[1] Adding 20 mum spectral observations to observations in the 812 mum region can significantly improve infrared cloud phase determination from both space and the surface. We demonstrate this with 7-20 mum radiance spectra of Arctic stratus clouds measured by a ship-based FTIR spectrometer during the SHEBA experiment. Our results are compared with phase classifications obtained from lidar, microwave radiometer, and radar data.