Abstract
A two-channel method has been developed to estimate the altitude of cirrus clouds over ocean areas with an expected altitude error ≤ ± 50 mb. Reflected radiation is used to estimate cirrus emissivity in the 10–11 μm spectral interval. The cirrus altitude is determined from the emissivity estimate, a registered 10–11 μm measurement, and a vertical temperature profile. Nimbus 3 Medium Resolution Infrared Radiometer measurements were used to establish the relationship between reflectance and 11-μm cirrus emissivity.