Uncertainty of Daily Isolation Estimates from a Mesoscale Pyranometer Network

Abstract

Abstract Daily insulation values at the earth's surface are required for modeling of biophysical processes and solar energy engineering design. Ground-based pyranometer networks have proliferated in recent years, offering improved spatial coverage for some regions, although data assimilation is daunting. Geosynchronous satellites can provide high-spatial-resolution observations, although data are not routinely available and estimates for snow-covered areas are problematical. The adequacy of the present array of ground-based pyranometers in the Midwest for estimating daily insulation was tested using kriging, a geostatistical technique. First, the usefulness of the kriging variance for predicting likely errors in spatial interpolation was demonstrated using a high-spatial-resolution satellite-derived insulation dataset. Then, daily data for 51 locations in four states were screened for errors using double-mass plots, a technique widely used in hydrology. For each day, a variogram was fit to the observation...