Final answer:
Universal kriging is an extension of ordinary kriging that incorporates additional covariates or auxiliary variables in the prediction process.
Step-by-step explanation:
Universal kriging is an extension of ordinary kriging that takes into account additional covariates or auxiliary variables.
In ordinary kriging, we assume that the mean and covariance of the process are constant throughout the study area, whereas in universal kriging, we allow the mean to vary as a function of the covariates.
For example, in ordinary kriging, we can predict the value of a variable at an unobserved location based only on the values at nearby observed locations. In universal kriging, we can include additional information such as elevation or land use as covariates to improve the prediction.