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The error is most evident for parameters where the gradient of the field is large and where a change in the nearest grid points or the interpolation weights used thus has a larger effect. Generally, the area to the west of the Andes and close to the equator suffers the greatest from this error.  This is because of the high gradients of many of the fields and its latitudinal proximity to the equator and to the west of the 0° meridian where the error is generally largest.

Which interpolations are affected ?

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