Surface Interpolation

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Selecting an interpolation method for sample data can result in vast differences in the surface layer output. In this lab, we compared surfaces derived from four different interpolation methods based on water quality data for Tampa Bay. These interpolation methods are Thiessen polygons (or Nearest Neighbor), Inverse Distance Weighted (IDW), spline regularized, and spline tension. 

Below is a screenshot of the surface layer created using the spline tension method. Of the four interpolation methods, I believe this method is the most effective at representing the Biochemical Oxygen Demand (BOD) concentrations throughout Tampa Bay because it most accurately reflects the values of the sample points.  



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