Therefore it seems difficult at present to use satellite observations to estimate the first aerosol indirect forcing unless some changes in cloud albedo could be tied to changes in aerosol concentrations under the assumption of
constant liquid water content.
The polarization differences at 37 and 85 GHz do not stem from the surface but are generated in regions of relatively homogeneous clouds having
high liquid water content.
«When carbon dioxide concentrations and temperatures rise, then mixed - phase clouds will increase
their liquid water content,» said Ivy Tan, a PhD candidate at Yale University who led the research, which investigated common clouds that contain both ice and water.
The Special Sensor Microwave Imager (SSM / I) radiometers provide brightness temperatures at three different frequencies (19.35, 37.0 and 85.5 GHz) from which are estimated: wind speed when not raining, integrated atmospheric water vapor content,
liquid water content, and a rain index.