Chapter 3 Analysis and Interpretation of Altimeter Sea Echo

Publisher Summary This chapter focuses on analysis and interpretation of altimeter sea echo. It discusses the physics behind the use of Barrick's model in information extraction and data interpretation. The convolutional form of Barrick's model is presented, demonstrating a simpler but efficient method for its inversion. The model is based on deconvolution by straightforward fast Fourier transform (FFT) algorithms. The important and interesting phenomenon called electromagnetic bias is discussed. In this phenomenon, the altimeter reckons the mean sea surface position to be, compared with its actual position, with all other errors/biases removed. The study of altimetric biases using models is presented. Models are developed and employed to study various factors, both instrumental and near-surface effects, that bias or distort the altimeter echo. Seasat is used to demonstrate their application. A double-deconvolutional-based algorithm is discussed for altimeter echo analysis that can handle various antenna error and rain biases, is computationally efficient, and outputs parameter uncertainties along with the parameters themselves. Concepts related to antenna pointing-error effects and rain effects on altimeter echo are also discussed in detail.

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