Towards retrieval of Antarctic sea ice using the SSM/I 85.5 GHz polarisation difference

In many sea ice retrieval algorithms the 85.5 GHz channels of the SSM/I (Special Sensor Microwave Imager) are not used because these channels are much more affected by weather systems than the lower frequency channels of the SSM/I. Despite the fact that the 85.5 GHz channels would allow for twice the spatial resolution of the lower ones the latter are used operationally for sea ice retrieval in polar regions. Here we propose an algorithm which uses the polarization at 85.5 GHz, PR(85), for the calculation of the total sea ice concentration in the Antarctic. Using monthly means of the PR(85) and its variation with time provides mean ice concentrations in agreement with ice concentrations calculated with the NASA-Team algorithm for values above 50%.