Minimize Applications

The MWR is operationally devoted to the determination of the wet tropospheric Radar Altimeter path delay. However, the two poles are the only places where the MWR can be used to map radiometric properties. The sea-ice and ice-shelf have actually there a slower time evolution than the ocean (the contribution of which is related to the wind), and than the atmosphere that, being very dry, adds but a very small contribution to the signal.

Antarctica Ice Cycle with the ERS-2 Microwave sounder

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The animation shows the evolution of the South pole ice cover from month to month, from August 1998 through April 1999.  Colours have been chosen so that the free ocean (lowest brightness temperatures) appears in blue, whereas the sea-ice (warmest brightness temperatures, due to its high emissivity) is in yellow.

Note that :

  • The central Antarctica continent (high plateau) has a very low brightness temperature, due both to its temperature and to its low emissivity.
  • On the continent, the  brightness temperatures follow the surface temperature evolution,  whereas the sea-ice cover diminishes until February (minimum), then again increases.

Mapping the radiometric properties of the ice-shelf -that has a slower time evolution than the atmosphere and the ocean - is a valuable input to understand the growth, decay and dynamics of ice sheets; fundamental in turn to understand environmental and climate changes.