Adaptation readiness and adaptive capacity of transboundary river basins

Transboundary river basins face significant threats from climate change, with the need for adaptation widely noted. In this paper we develop a theoretically-rooted indicator-based evaluation framework to identify transboundary river basins where the need for adaptation support is pronounced and prioritize where attention is best placed. The framework combines indicators which capture the broad level potential to adapt (adaptive capacity) and the actual preparedness for adaptation (adaptation readiness) at the level of transboundary institutions. Adaptive capacity and adaptation readiness have not previously been evaluated and compared within a single framework, and by combining them we gain a more comprehensive and nuanced basis for characterising and evaluating the adaptation landscape and diagnosing opportunities and constraints for adaptation. We apply the framework to 42 transboundary basins in Mediterranean Europe, the Middle East, North Africa and sub-Saharan Africa, which account for 15 % of global transboundary river basins, are home to over 550 million people, and cover 8 % of Earth’s total land area. We find: 1) There is widespread need for improving national and transboundary institutional support for adaptation spanning basins of various economic, physical, and demographic characteristics; 2) Many transboundary basins in Africa have low adaptive capacity, but were found to have high readiness to begin adapting if resources were available; and 3) Improved coverage of River Basin Organisations and treaties with mandates to recognise and respond actively to climate change would underpin adaptation efforts across basins.