Monitoring and Obssrvation of Fohn Wind in Hong Kong Using a Multi-channel, Ground-based Microwave Radiometer
نویسنده
چکیده
The performance and application of a multlchannel, ground-based microwave radiometer in the monilori:rg of Fohn wind was studied in an experiment conducted in Hong Kong in 2004. Three scanning modes (zenith, elevation and 15degree elevation) were tried out fo: the radiometer to monitor lhe low-level temperature inversions upwiad of the hills. Thermodynamic profiles retrieved from the zenith mode compared the best with the :adiosonde measwements. For inversions associated with low clouds, an empirical method based on saturation temperature appeared to improve temperatre retrieval. When placed downwind of the hills, the radiometer captured very well the warming and drying of the boundary layer as a result of Fohn wind. The frequency spectrum of the brightness temperature from the radiorneter was found to follow a -5l3 law. A quantity dervied from the specarum tumed out to vary in a manner similar to the intensity of air turbulence in a strong Fdha wind case. Keyworrls microwave radiometer, Fbhrwind, turbulence, windshear
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