Adaptive smoothing approximation in the construction problem for hydrometeorological fields

A smoothing approximation procedure that allows one to adapt a piecewise linear isoline to its representation by polynomials up to the third order is considered. The smoothing approximation reduces the effect of linear interpolation errors in isoline plotting. The procedure is based on the least-squares method. The data replenishment methods of spline cubic interpolation, most commonly used in practical work, are analyzed. A universal approach for the formation of boundaries of isoline areas on the basis of data availability at the computational grid nodes is discussed.