Significance: Jordan is facing an unfolding water crisis, exacerbated by climate change and conflict-induced refugee influxes. We present a freshwater security analysis for the country, enabled by an integrated systems model that combines simulation of Jordan’s natural and built water environment with thousands of representative human agents determining water allocation and use decisions. Our analysis points to severe, potentially destabilizing, declines in Jordan’s freshwater security. Without intervening measures, over 90% of Jordan’s low-income population will be experiencing critical water insecurity by the end of the century. To gain a foothold on its water future, Jordan must enact an ambitious portfolio of interventions that span supply- and demand-side measures, including large-scale desalinization and comprehensive water-sector reform.

Commonly described as the “water tower for Asia,” the Hindu Kush Himalaya (HKH) plays an important role in ensuring water, food, energy, and environmental security for much of the continent. The HKH is the source of ten major rivers that provide water—while also supporting food and energy production and a range of other ecosystem services—for two billion people across Asia. This chapter takes stock of current scientific knowledge on the availability of water resources in the HKH; the varied components of its water supply; the impact of climate change on future water availability; the components of water demand; and the policy, institutions, and governance challenges for water security in the region.