Influence of hydroclimatology and socioeconomic conditions on water-related international relations

Climatic and environmental changes and a rising water demand have increased the competition over water resources and have made cooperation between countries that share a transboundary river an important issue in water resources management and hydropolitics. Yet in river basins around the world, international conflict and cooperation are influenced by dififerent factors, and general conclusions about forces driving conflict and cooperation have,been difficult to draw. Using global data, this study investigates how combinations of hydroclimatic, socioeconomic and political conditions influence the Pattern of water-related international relations (WIR). The data complexity required several steps of statistical analysis. First, patterns of WIR were defined by subjecting the basins' aggregate history of political event data to cluster analysis. Using the classified WIR-patterns as a dependent variable, the study then explores the influence of combinations of explanatory variables on international relations by the means of a multivariate classification tree model. The obtained model, which determines a basin-country-share most likely WIR-class by its hydroclimatic, socioeconomic, and political characteristics, correctly classifies two-thirds of the basin shares. The tree rules suggest that hydroclimatic variability and population density are most influential in and to sub-humid basins, while socioeconomic and political factors seem to be more important in determining WIR in humid basins. The application of the model to all international basins worldwide illustrates its potential for the assessment of the global water-related international relations processes.