The Global Food‐Energy‐Water Nexus

Abstract

Water availability is a major factor constraining humanity's ability to meet the future food and energy needs of a growing and increasingly affluent human population. Water plays an important role in the production of energy, including renewable energy sources and the extraction of unconventional fossil fuels that are expected to become important players in future energy security. The emergent competition for water between the food and energy systems is increasingly recognized in the concept of the “food‐energy‐water nexus.” The nexus between food and water is made even more complex by the globalization of agriculture and rapid growth in food trade, which results in a massive virtual transfer of water among regions and plays an important role in the food and water security of some regions. This review explores multiple components of the food‐energy‐water nexus and highlights possible approaches that could be used to meet food and energy security with the limited renewable water resources of the planet. Despite clear tensions inherent in meeting the growing and changing demand for food and energy in the 21st century, the inherent linkages among food, water, and energy systems can offer an opportunity for synergistic strategies aimed at resilient food, water, and energy security, such as the circular economy.

Determinants of the ratio of actual to potential evapotranspiration

“…Terrestrial evapotranspiration (ET) is the sum of soil and open water evaporation, plant transpiration, and rainfall interception by the canopy. ET is a critical process linking water resources (Gedney et al, ; Oki & Kanae, ) and carbon–climate feedbacks (Field, Jackson, & Mooney, ; Ponce‐Campos et al, ; Shukla & Mintz, ; Zeng, Piao et al, ), and understanding the ET process has important implications for agricultural management (Allen, Pereira, Raes, & Smith, ; D'Odorico et al, ; Fisher et al, ). When surface water supply is unlimited, ET reaches an upper limit bounded by atmospheric evaporative demand, also known as potential evapotranspiration (PET).…”

Effects of urbanization on food-energy-water systems in mega-urban regions: a case study of the Bohai MUR, China

“…Some previous studies focused on the FEW flows and nexus in watersheds, cities, megacities and regions (Kennedy et al 2015, Endo et al 2017, Cai et al 2018, Gragg et al 2018, Taniguchi et al 2018, Yang and Wi 2018, which furthered our understanding of the internal characteristics of the system. Studies have also shown that changes in one system have profound effects on other systems, because of the interdependencies and interactions between food, energy and water subsystems (Hoff 2011, Al-Saidi and Elagib 2017, Scanlon et al 2017, Cai et al 2018, D'Odorico et al 2018. In addition, the external factors, such as rapid population growth, urbanization, economic development and climate change, will affect the production and supply of these resources and enhance the demands for food, energy and water (Hanjra and Qureshi 2010, Allan et al 2013, Seto and Ramankutty 2016, Qin et al 2019.…”

Impacts of Mainstream Hydropower Development on Fisheries and Human Nutrition in the Lower Mekong

“…Growing human populations and economic development drive increases in global demand for food and energy, interlinked sectors that heavily rely on limited water resources (World Economic Forum, 2011). Dams produce hydropower, provide water for food production, modify water flows, and restructure fisheries, placing them at the center of the challenge to sustainably manage the food-energy-water (FEW) nexus (D'Odorico et al, 2018). With 3,700 large hydropower dams planned worldwide (Zarfl et al, 2015), understanding FEW tradeoffs is increasingly important.…”