DocumentCode :
806050
Title :
A physics-based parametric representation of the wind direction signal in sea surface microwave brightness temperatures
Author :
Baum, Eric ; Hauss, Bruce
Author_Institution :
Northrop Grumman Space Technol., Redondo Beach, CA, USA
Volume :
41
Issue :
10
fYear :
2003
Firstpage :
2364
Lastpage :
2367
Abstract :
Polarimetric passive measurements of sea surface brightness temperature have been proposed as a means of inferring wind speed and direction. A limited set of circle flight measurements of the wind direction dependence has demonstrated that there may be enough independent information in the polarimetric measurement to make this feasible. A predictive model by Yueh reproduces the observations closely enough that the dominant mechanisms are probably included. Optimizing the fit of this type of model with a growing dataset is made difficult by the close coupling of the Yueh approach with a particular wind-wave spectral model. This makes it unclear as to how to parameterize the model, a prerequisite of any systematic optimization technique. Here, we present an alternate formulation, using the Baum-Irisov model to isolate the particular properties of the wavy ocean surface that affect the radiance, in the form of six discrete parameters. Iterative local linearization techniques are used to optimize the values of these parameters with respect to any large dataset. The parameters are functions of only two variables (radiometer frequency and wind speed), while the effects of incidence angle, polarization, sea surface temperature, salinity, and wind direction are derived front the model. Since the data need only be binned by these two variables, a relatively small number of on-orbit/ground-truth datasets is required to evaluate the parameters.
Keywords :
atmospheric boundary layer; ocean waves; remote sensing; wind; Baum-Irisov model; Yueh approach; incidence angle; iterative local linearization techniques; physics-based parametric representation; polarimetric measurement; polarimetric passive measurements; polarization; salinity; sea surface brightness temperature; sea surface microwave brightness temperatures; sea surface temperature; wavy ocean surface; wind direction signal; wind speed; wind-wave spectral model; Brightness temperature; Linearization techniques; Microwave radiometry; Ocean temperature; Predictive models; Sea measurements; Sea surface; Temperature measurement; Velocity measurement; Wind speed;
fLanguage :
English
Journal_Title :
Geoscience and Remote Sensing, IEEE Transactions on
Publisher :
ieee
ISSN :
0196-2892
Type :
jour
DOI :
10.1109/TGRS.2003.815970
Filename :
1237407
Link To Document :
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