Demonstrations and exercises for Rutgers University oceanography course 16:712:615 Geophysical Data Analysis
In folder matlab there is presently a set of MATLAB Live scripts demonstating aspects of Optimal Interpolation. The methodology follows Chapter 4, The spatial analysis of data fields, in: Thompson, R.E. and W. J. Emery (2014) "Data analysis methods in physical oceanography," Elsevier, https://doi.org/10.1016/C2010-0-66362-0
The three exercises use data depicting the occurrence of Tropical Instability Waves in the eastern equatorial Pacific Ocean. For an overview of the dynamics of Tropical Instability Waves, see: Willett, C.S., Leben, R.R. and Lavín, M.F., 2006. Eddies and tropical instability waves in the eastern tropical Pacific: A review. Progress in Oceanography, 69(2-4), pp.218-238. https://doi.org/10.1016/j.pocean.2006.03.010
Exercise 1: Estimate covariance length scales from pseudo-observations of SST generated by sampling output from the NOAA RTOFS ocean model. This Live script demonstates how to compute a binned-lagged covariance function from a sample data set and use this to fit covariance length scales and signal variance appropriate to the data set. These fitted parameters are used in Exercise 2 to perform an optimal interpolation of the data. It should be stressed that if the covariance functional form or chosen length scale and other parameters do not represent the underlying data well, the interpolation can be far from "optimal".
Exercise 2: Optimal Interpolation of pseudo-observations generated by sampling output from the NOAA RTOFS ocean. This live script allows the user to vary the sampling resolution and the magnitude of the simulated observational error to explore the sensitivity of the interpolated field in comparison to the "truth".
Exercise 3: Optimal Interpolation of Infrared SST observations from Low Earth Orbiting (LEO) satellites. This live script parallels Exercise 2, but uses actual ocean observations acquired by infrared imagers on LEO satellites during November 2022.
All code is (c) John L. Wilkin - [email protected]