Spatially interpolated time series of δ18Ο in Eastern Mediterranean precipitation

The water cycle is one of the key parameters that determine the climatic character of a region. Stable isotopes have long been established as a valuable tracer in the study of the origin, dynamics and interactions between the various components of the hydrologic cycle, both of the present and of the past. Even though significant efforts have been made, the spatial and temporal coverages of the available water isotope data are far from satisfactory. Statistical modeling and interpolation of existing measurements is a possible answer to this problem. This work is based on the experience gained by several recent studies in order to generate 0.5° × 0.5° gridded monthly time series of δ18Ο in the precipitation of the Eastern Mediterranean. The empirical model incorporates geographical and topographical data in order to capture the main modes of the spatial variability of the isotopic composition of precipitation, while the incorporation of meteorological data time series provides the necessary temporal variability. Overall, despite the rather coarse spatial resolution of the existing isotopic data, the applied methodology provides a satisfactory reproduction of the measurements.