The food/water/climate nexus

In 2010-12 850 million (or 15%) of the world population were chronically undernourished (FAO 2012: The State of Food Insecurity in the World). In fact this number has dropped from 1000 million in 1990, a result of increasing agricultural production (between 2 and 4% per annum) over the last 50 years - although since 2008 this increase may have stalled. More than 40 percent of the increase in food production has come from irrigated areas, which have doubled in size, primarily in Asia (FAO Statistical Year Book 2013). The rest has come from increasing yields through improved fertilizer input and technology. These trends are not uniform across the world, with much higher growth in Asia compared to Africa. These dramatic improvements in food production have come at an environmental price. Groundwater levels have dropped over most of the major irrigated regions (Wada et al., 2010; Rodell et al., 2009), high nutrient use has created a web of pollution affecting the environment and human health and there are continuing pressures on forest and natural regions.