The primary goal of HadCRU_MLE is to combine instrumental observations with physically realistic statistical models to produce maximum likelihood estimates of surface temperature anomalies and other physical quantities of the Earth. Additional goals of HadCRU_MLE include correcting for biases in estimates, producing the most efficient estimates given the available data, and better quantifying uncertainties. The maximum likelihood estimation approach allows for estimated fields to be temporally and spatially complete for the entire instrumental period (since 1850) and for the entire surface of the Earth. HadCRU_MLE uses source datasets primarily from the Met Office Hadley Centre and the Climate Research Unit of the University of East Anglia. This project has not received funding from any source.