While we know how global changes in freshwater pose risks to humans and ecosystems, we know less about how people and ecosystems will respond to these global freshwater challenges.
When groundwater comes to the surface, sunlight and air convert organic molecules to greenhouse gases. That’s going to be a problem as we will need this water more as the world warms.
Groundwater has the potential to support broad economic, humanitarian and social development in sub-Saharan Africa, as it has in other regions globally.
Water is central to adapting to climate change, but very few of the strategies put in place to respond to water hazards or ensure its availability have been evaluated.
Groundwater is the second-largest store of water on Earth. Governments and industry use groundwater reservoirs to store waste, but it may also have environmental functions that haven’t been revealed.
More than 40 per cent of natural wetlands in the Canadian Prairies have been lost due to drainage, and the impacts associated with this are largely unmitigated.
As surface water diminishes in the Western US, people are drilling deeper wells – and tapping into older groundwater that can take thousands of years to replenish naturally.
Cities and farmers in the Southwest are resorting to unsustainable strategies to pull in more water. Iran has tried many of these strategies and shows how they can go wrong.
Debra Perrone, University of California, Santa Barbara and Scott Jasechko, University of California, Santa Barbara
The US has one of the highest groundwater use rates in the world. When wells run dry, households may opt to conserve water, find new sources or sell and move.
Large areas targeted for forest restoration in Africa are covered by savanna and grassland, which provide important ecosystem services that would be lost should they be converted to forests.