Signature of clouds over sea ice detected by the Special Sensor Microwave/Imager (SSM/I)

Quantitative determination of cloud parameters over sea ice using the radiometric measurements at SSM/I frequencies has been difficult due to the strong and highly variable surface emissions from sea ice. The authors try to suppress these variations using a ratio of polarisation differences at two frequencies, which is called the R-factor. Using a simple radiative transfer equation for a one-layer atmosphere, they proved that the surface signal and the atmospheric signal can be easily separated in the logarithmic expression of this R factor. If it is valid to assume that the surface parameter changes within two days are not very significant, the day-to-day variation of the cloud parameters (mainly the cloud liquid water) over sea ice can be detected using the SSM/I measurements.