Let’s Avoid Water “Haves” and “Have-Nots”

New Data Suggests We Need Urgent Action

Access to water is changing worldwide, requiring attention from policymakers and the public. We now have 14 years’ worth of satellite data that quantifies the rates at which all regions on Earth are gaining or losing water, thanks to the unique NASA Earth-observing mission called the Gravity Recovery and Climate Experiment (GRACE), which measured the very tiny space-time variations in Earth’s gravity field from 2002 to 2017, This data allows us to produce maps that show how water security is at a greater risk than most people realize.

Throughout the map’s development, one of the most concerning data points has been persistent, distinct patterns that define emerging classes of water “haves” and “have-nots” worldwide. These patterns show that the high-latitude regions and global tropics are getting wetter, while the mid-latitudes, the arid to semiarid belt sandwiched between these zones, are drier. A series of Intergovernmental Panel on Climate Change (IPCC) reports has long predicted this pattern of wet getting wetter and dry getting drier.

Climate Hot Spots Are Intensifying

However, our latest study and an earlier report from our team show that it is happening now. Hot spots in which drought extremes have been intensifying at dangerously high rates are also apparent on the map. Key regions include California and Texas, where droughts have occurred, and southeastern Brazil, where Sao Paulo nearly ran out of water. Chronic droughts have occurred in Eastern Europe, while in the Caspian-Aral Sea region in Asia, long-term drought is drying out once-great inland seas. Over 2 billion people already lack access to safe drinking water at home, and by 2025, over half of the world’s population will reside in water-stressed areas. These numbers will increase significantly if climate change and population growth follow or exceed predicted trajectories. The disappearance of water from several hot spots on the map raises essential questions about whether the world is prepared for potential waves of displaced people.

The world needs more than technological innovations to meet global water challenges. There are areas, however, in which we can make progress immediately. Agriculture has great potential for water saving by improving efficiency through more precise and focused irrigation and by breeding plants for drought tolerance. Around the world, surface water and groundwater must be managed jointly as components of one interconnected water supply. Poor monitoring and management of groundwater relative to surface water, as is typical in much of the world, has contributed to its rapid disappearance.

Individuals Must Take Action

As individuals, we can take action by using more efficient plumbing, reducing outdoor watering at home, and adjusting our diet to include foods that require less water. We must also require our elected officials to commit to solving our water concerns. Reliable scientific information exists to help guide them.

If governments, nonprofits, development banks, academic researchers, industry, and policymakers unite, we can turn our freshwater challenges into a net positive.

By opening venues for discussing water policy, sharing data, and developing new physical—and social—infrastructure, we can create a new worldwide water diplomacy that treats this universal, vitally needed resource as an inspiration for cooperation rather than conflict.