Additionally, climate change is already altering hydrological regimes everywhere, Graziano da Silva said, citing estimates that around one billion people in dry regions may face increasing water scarcity in the near future. These are regions with a high concentration of extreme poverty and hunger.
Agriculture a major cause and casualty of water scarcity
Agriculture is both a major cause and casualty of water scarcity. Farming accounts for around 70 percent of freshwater withdrawals in the world today and also contributes to water pollution due to pesticides and chemicals.
To tackle these challenges, the international community created a stand-alone sustainable development goal (SDG) on water and wove better management of this key natural resource throughout the entire architecture of the SDGs, Graziano da Silva said. Improved water matter is particularly important to the SDGs related to extreme poverty, hunger and malnutrition, and climate change, he added.
"Agriculture and food systems bring all of these global goals together and provide opportunities for a transformational change," he said.
The FAO director-general urged listeners to rise to the food security challenges posed by water scarcity on two fronts: first, promoting ways to both use less water and use it more efficiently, and secondly, by taking steps to secure access to water especially for poor family farmers.
Doing so will not prevent a drought from occurring, he said, but it can help in preventing droughts from resulting in famine and socioeconomic disruption.
Graziano da Silva also said that cutting back on food waste has an important role to play in using water more wisely. Each year, one-third of the food we produce is either lost or wasted that translates into a volume of agriculture water wasted equal to around three times the volume of Lake Geneva, he said.
Water and your food, by the numbers
FAO projects that irrigated food production will increase by more than 50 percent by 2050, but the amount of water withdrawn by agriculture can increase by only 10 percent, provided that irrigation practices are improved and yields increase.
The world contains an estimated 1,400 million cubic km of water. But only 0.003% of this amount, about 45,000 cubic km, are "freshwater resources" that can be used for drinking, hygiene, agriculture and industry. Not all of this water is accessible because part of it flows into remote rivers during seasonal floods.