Abstract:
From November 2006 to June 2007 a field experiment
‘Tanashi Experiment’ was conducted in a farm of the University
of Tokyo, Japan. Continuous ground measurements of
meteorological variables, soil moisture and temperature profiles
and vegetation status have been taken. At the same time, the
ground based microwave radiometers (GBMR) are employed to
provide accurate field measurements of brightness temperature
up-welling from the plot, at the frequencies of 6.925, 10.65, 18.7,
23.8, 36.5 and 89 GHz. The scientific objectives are presented in
this paper and the corresponding experiment set-up is described.
The influences of vegetation layer on the brightness of various
frequencies are analyzed. The TB of all frequencies and
polarization is found to be saturated and reach same values when
vegetation water content larger than 4 kg/m
. Based on the
analysis of winter wheat experiment results, the Polarization
Index (PI) of 6.9GHz and the Index of Soil Wetness (ISW)
calculated from 18GHz and 6.9GHz horizontal polarization were
recommended to compose the look up table. Potential
applications of this winter wheat microwave radiometer
observation are the development and validation of land surface
variables retrieval algorithm and the study of land surface
process and the land atmosphere interaction, and.
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