Abstract
A climatic regionalization of Saudi Arabia that aims to classify the country into several homogenous groups is carried out, by grouping similar long-term climatological features for precipitation and air temperature. Twenty-seven stations are selected across Saudi Arabia for the analysis and 1985-2010 (26years) is chosen as the common period. The employed methodology is a combination of mathematical and statistical techniques (principal components analysis and correlation); and a rather subjective physically detailed comparison with the long-term climatology and topography for Saudi Arabia. Five groups have been identified: group A (Northern), B (Red Sea Coastal), C (Interior), D (Highland) and E (Southern). Each of the climatic groups exhibits a unique feature (with strong similarities among stations that belong to the same group), especially in terms of inter-annual fluctuations and the degree of seasonality. This simplified overview of climatic characteristics is beneficial for assisting with economic planning, especially for any semi-arid or arid land that is naturally vulnerable to climatic variability and extremes. The classification method used in this study, however, would be applicable for similar studies on regionalization in other regions.