Director, Columbia Water Center, Earth Institute, Columbia University
Can the world support the aspirations for food and energy of the 7 billion people that now inhabit it? Will we meet the needs of the additional 2 billion people that we expect will be here by 2050? More than ever, the answers to these questions depend on how wisely we use the world’s fresh water resources — to both meet our own needs and to sustain the basic water requirements of all life that inhabits our blue planet.
In the late 20th century, as a result of the Green Revolution, global grain yields surged dramatically. However, the higher energy intensity required (largely for fertilizers production and pumping ground water) along with associated water resource degradation has emerged as a serious challenge to the movement. Water tables in many countries, including the USA, India and China have dropped significantly in the last 20 years, indicating that we have exceeded our renewable water budget and are unsustainably mining the resource.
Water is a renewable resource, whose availability varies from place to place, and by month and year. Droughts and floods are omnipresent hazards for most societies, leading to loss of crops, property and lives; as the earth’s climate changes, experts believe the frequency of both may increase. Places that are arid may become more so, while the frequency of intense precipitation may increase almost everywhere. Thus, understanding, predicting and adapting to climate is critical for water and food security. Adaptation requires water and food storage, and also judicious choices as to what to grow where, from a global and from a regional perspective.
In the last few years droughts and floods led to low grain production in key producing nations, causing a dramatic jump in global food prices and revealing how thinly traded the global food market is. Only about 10 percent of wheat and rice production is actually traded globally, which means that small deficits in production have significant impacts as nations restrict exports in the interest of domestic food security. Given their water and productivity constraints, the Chinese have been securing land and promoting cultivation of crops that they need in Africa and South America, thus creating a secure import supply chain in the face of the volatility in global markets.
Agriculture consumes more than 70 percent of the freshwater we use, but depending on how it’s computed, globally the average water use efficiency of farming is only 10 to 30 percent. At the same time, crop yields per acre in the most productive parts of the world are often 10 times greater than those in many developing countries. These developing countries, especially in Africa, are expected to contribute the bulk of global population growth. Therefore, meeting future food needs without further stressing global water resources actually appears quite feasible, if water use efficiency can be improved and crop yields increased in the most vulnerable parts of the world.
This gap between the most and least productive and water-efficient agriculture poses an interesting opportunity for the United States. Not only is the US relatively well endowed with water, it also has some of the highest productivity in agriculture, high rates of innovation, and is a major net agricultural exporter.
In the late 20th century, the US transitioned from a high tech economy to a high finance one, sparking economic bubbles that eventually burst. At a time when the economic future of the country is unclear, jobs are hard to get, and the country is questioning its national competitiveness, we need to ask whether the US expertise in climate, water, agriculture, food processing and energy technologies provides a new opportunity to position it as a global leader that can prosper on the strength of its innovations in these basic resource areas.
Unlike China, whose agricultural expansion abroad appears to be a strategic government initiative to meet domestic needs, US efforts have been largely targeted toward agricultural development through the USAID and USDA programs. Whereas the success of the US programs has varied depending on local uptake and capacity, the Chinese are following a model closer to leasing land and managing production, thus potentially controlling productivity more tightly. Once we see the problem through the lens of global food and water security risks in the face of climate dangers, a growing population and energy/environment constraints, it follows that given its resources, the US can and should play a greater strategic role in shaping the water and food future of the planet.
In addition to the inevitable political maneuvering, this new global strategic role requires focused development and implementation of appropriate soft and hard technologies.
The soft technologies would facilitate the selection of the most optimal locations and practices to grow specific crops to make the best use of water and energy resources to meet global and local food needs; the identification of when and how to store food or water; predictions of climate and weather to anticipate and ameliorate the effects of drought; how to manage trade so that producers are delivered high stable value, while reducing price volatility and shocks from shortages.
The hard technologies would facilitate improvements in productivity and efficiency across the board, and their deployment in a global context would strategically address the limitations in many parts of the world where poverty leads to barriers in implementation of high technology.
The US led the Green Revolution in the 20th century. It is time to do it again, but for the global good. The stakes are higher. The global water crisis is upon us, and it is time that the US played a direct role in the sustainable development of the world’s water and food. It would help not just the global poor and freshwater ecology. It would strengthen the backbone of the US economy, and provide an avenue for our youth to be global emissaries with a sense of purpose.