Where there is water, there is life. Water is powerful yet fragile – an object of conflict and, at the same time, a unifying medium. Continuing, accelerated changes in the global water cycle are to be expected in the future. The effects of climate change, the overexploitation of water resources, the unequal distribution of water, the loss of ecosystem services, and threats posed by water-related health risks will continue to intensify. The assumption of stationarity – i.e. the idea that natural systems exhibit predictable variability within a defined time window on the basis of empirical observations – is no longer valid in the face of climate change. This will increasingly lead to threatening situations that are beyond the spectrum of human experience and could escalate into regional water emergencies. In extreme cases, situations arise in which the limits of controllability are exceeded, societal structures and ecosystems are substantially destabilized, and there is no longer any room for manoeuvre. These are threatening patterns with a planetary dimension.
A water-mapping initiative consisting of a scientific platform and a panel of experts should be launched internationally in order to recognize crisis developments at an early stage and avert regional water emergencies with a planetary dimension. Furthermore, there should be a systematic international exchange on effective adaptation and resilience strategies. These challenges face all countries, and an International Water Strategy should be sought to meet these challenges as a global community.
