Observed precipitation and potential Evapotranspiration for the winter (left panel) and summer periods (right panel) for Oakville, Napa Valley, California (USA, 38,3^∘ North, 122,3^∘ West) and Williamstown in the Adelaide Hills (Australia, 34,7^∘ South, 138,9^∘ East). Avignon data from France have been added to illustrate how different regional situations are in broadly defined “Mediterranean climates”. Data show 10-year running mean values. Observed data were from the US California data provision system on integrated pest management at the University of California, Davis and the Australian Bureau of Meteorology, Australian Government and the French INRA CLIMATIK, Agroclim database.