If the overall water resources in river basins were acknowledged and managed better, future food crisis could be significantly reduced, a new study has found.
The challenge of meeting future water needs under the impacts of climate change and rapidly growing human demands for water may be less bleak than widely portrayed, according to the study published in the May issue of the journal Water Resources Research.
The current approach to water management considers only "blue water," that is river discharge and groundwater, said the study conducted by a team of Swedish and German scientists from Stockholm University, Stockholm Environment Institute and Potsdam Institute for Climate Impact Research.
This limits the options to deal with increasing water scarcity and water risks induced by climate change, the study said.
Under those conditions, over 3 billion of the current world population are estimated to suffer from severe water scarcity, according to the study.
The new analysis which additionally accounts for "green water," that is water in the soil that stems directly from rainfall, suggests that the actual number is under 1 billion.
It also shows that wise water management can lift billions out of water poverty.
The analysis quantifies for the first time the opportunities of effectively using both "green" and "blue" water to adapt to climate change and to feed the future world population.
"This opens a new area of investments for climate adaptation and a window to achieve a much needed new green revolution in poor countries in the world," the researchers said in the study.
"Our analysis shows that many water-short countries are able to produce enough food for their populations if green water is considered and managed well."
The study presents evidence that a better use of green water can form the basis for a new green revolution. It may also provide the basis for building resilience towards more frequent and intense floods, droughts and dry spells under human-induced climate change.
Water Resources research site: http://www.agu.org/