Spatial trend analysis and uncertainty estimates of acid precipitation data in Ontario

The use of the Simple Kriging and Universal Kriging methods to estimate the spatial trend in the spatial data is examined. By following the approach of the Simple Kriging methods, a new Modified Kriging method has been developed for better presentation of the spatial pattern of spatial data and error estimation. Results of comparison indicate that the Modified Simple Kriging method can provide better interpolation and error estimation for the mathematical functions. Although the results of practical interpolation obtained by using the three methods are quite comparable, the error estimates by the Simple Kriging and Universal Kriging methods are greater than those of the modified Simple Kriging method and the one standard deviation confidence belts are overlapping each other. This may indicate that the error estimations from the Simple Kriging methods are too great.The Universal Kriging method provides the greatest error estimation among these three methods. Although those results indicate that there is no advantages of using the Universal Kriging method, further study on the proper formula for the generalized covariance function should be carried out. The heart of the Universal Kriging method is to find the correct covariance function, since the isopleths and the error of estimation are verymore » sensitive to it.« less