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Ground-based millimeter and submillimeter-wave radiometry for the observation of the Arctic atmosphere

Microwave radiometers working at millimeter and submillimeter wavelengths show enhanced sensitivity to low contents of water vapor and cloud liquid in the atmosphere with respect to conventional radiometers working at centimeter wavelengths. This enhanced sensitivity gives particular interest to high-frequency radiometers for the accurate observations in extreme dry and cold conditions typical of the polar regions. Recent outcomes from modelling and experimental campaigns in the Arctic are hereafter presented and discussed, to demonstrate the feasibility and the accuracy of millimeter and submillimeter radiometric observations for the ground-based retrieval of thermodynamical properties of the atmosphere over polar regions.