Adaptation through Water 2025

Why water is the ideal point of entry to adaptation 2 Addressing water-related adaptation needs could significantly advance Southeast Asia’s overall adaptation and resilience agenda. Water is essential to the natural and the man- made environments. It is how we experience climate change most directly – through varying levels of precipitation that produce floods or drought, and through rising sea levels. Water underpins all socio-economic development and virtually every human and natural system: whether food, agriculture and health, human settlements and infrastructure, or nature and its ecosystems. As such, it is well-suited to be the centre of and starting point for, adaptation efforts. More broadly, addressing water-related adaptation needs could significantly advance Southeast Asia’s overall adaptation and resilience agenda. The Global Commission on the Economics of Water (GCEW), a group of policy-makers and researchers dedicated to advancing how societies govern, use and value water, emphasizes water’s role as a global public good. The commission holds the view that the water cycle includes not only “blue” water – the visible bodies of water that most water management approaches concentrate on – but also “green” water – the water stored as moisture in soil and vegetation that is a critical freshwater resource. Green water returns to the air through evaporation and transpiration and as it circulates, it creates about half of all the rain that falls on land (see Figure 1). EvapotranspirationLand precipitation Green water Blue waterAtmospheric water transport Ocean evaporation Ocean precipitation Groundwater recharge GroundwaterGroundwater dischargeRunoffLand OceanThe hydrological cycle: blue water and green water FIGURE 1 Source: Global Commission on the Economics of Water (GCEW).5