What is "regression-kriging"

In applied statistics, regression-Kriging (RK) is a spatial prediction technique that combines a regression of the dependent variable on auxiliary variables (such as parameters derived from digital elevation modelling, remote sensing/imagery, and thematic maps) with Kriging of the regression residuals. It is mathematically equivalent to the interpolation method variously called universal Kriging and Kriging with external drift, where auxiliary predictors are used directly to solve the Kriging weights.