A new study out of Stanford University finds extreme temperatures are cutting wheat yields by 20 to as much as 50 percent, a finding worse than previously estimated. FSE center fellow David Lobell and his colleagues used nine years of satellite measurements of wheat growth in northern India's breadbasket, the Indo-Gangetic Plains, to analyze rates of wheat ageing after exposure to temperatures higher than 34 degrees Celsius. 

Extreme heat beyond the plant's tolerance zone damages photosynthetic cells. This causes wheat to age faster, reducing the length of the growing season and the amount and size of the wheat grains. The team's crop models found that a two degree increase in temperatures would reduce the growing season by nine days, yielding 20 percent less wheat.

As the world's second-biggest crop, lost wheat yields may become a major threat to global food security. Especially given the projection that global yields need to rise 50 percent by 2050 to feed a growing, more affluent population. The results imply that warming presents an even greater challenge to wheat than previous studies estimated, and that the effectiveness of adaptations will depend on how well they reduce crop sensitivity to very hot days, particularly in areas of the world such as India already experiencing warming conditions.

Stanford University's Center on Food Security and the Environment (FSE) takes a global and multifaceted approach to issues of food security by tackling both the supply and demand side of the equation. By recognizing that food security issues in the 21st century are intimately tied to climate change, FSE looks at the root causes of our problems and helps to create sustainable solutions to feed those in need around the world.

The demand for food, feed and fuel will continue to rise as the world population grows and becomes more affluent. Meeting this demand will be especially challenging because of global warming, say climate experts, and the impacts of climate variability could make food markets even more volatile, adds Rosamond L. Naylor, professor of environmental Earth system science at Stanford University.

Naylor led a symposium on the compound effects of climate change and climate variability on food security at the annual meeting of the American Association for the Advancement of Science (AAAS) February 17th.

The symposium focused on two examples of climate variability: changes in growing-season temperature extremes beyond the range observed in the historical record, and changes in the El Niño–Southern Oscillation (ENSO) phenomenon – the most energetic form of year-to-year climate variability known.

Panelist David S. Battisti, professor of atmospheric sciences at the University of Washington, addressed key challenges in assessing the impact of extreme temperatures in coming decades. According to Battisti, global warming models forcast that temperature variability will increase as the average temperature warms, greatly compounding the likelihood of extreme heat and droughts. Unfortunately, these models typically have too much temperature variability in their simulations of present-day climate, he said. Battisti's talk focused on the cause of these modeling biases and their impact on climate forecasting.

Panelist Daniel J. Vimont, associate professor of atmospheric and oceanic sciences at the University of Wisconsin-Madison, discussed the impacts of El Niño in a warmer world. ENSO impacts can be severe in regions in and surrounding the tropical Pacific, and can extend around the globe, he said. ENSO variability – its return period and intensity – are very sensitive to changes in mean conditions in the tropical Pacific, he added, but these conditions are notoriously difficult to simulate using the present generation of global climate models. Vimont presented results from the linear ocean atmosphere model (LOAM), a new scientific tool for estimating global warming's impact on ENSO variability.

Naylor addressed the impacts of climate on global markets for major staple commodities, which are already under pressure from increased population-, income-, and energy-driven demands. She outlined the potential effects of climate variability on regional trade patterns, price volatility, policy responses and human welfare. 

Mark Shwartz is the Communications/Writer at Precourt Institute for Energy at Stanford University.

While many of us here in the US wake up concerned about political, economic, and military unrest at home and abroad, billions still wake up with more basic, human security concerns, opened FSE director Rosamond L. Naylor in a plenary connecting climate, energy, food, water, and health.

Are we going to have enough to eat today? How am I going to feed my family or care for family members struggling with HIV/AIDS and other infectious diesease? Is there enough water to drink, bathe, and still water my crops?

Naylor emphasized the need to bring these human security issues back into the forefront of our global conscious. While these are 'humanitarian needs at the core', they are also related to national and international security.

"When people are desperate enough, and we've seen this particularly with the food price spike in recent years, they take to the streets, and sometimes when they take to the streets they realize they are disgruntled about a number of things in addition to food prices," said Naylor.

The Arab Spring and wave of rebellions throughout the Middle East last year demonstrate the connections between food security, unmet basic needs, and national security. It has been a chaotic time for world food markets, said Naylor.

Naylor's global statistics are discouraging. Over a billion people still suffer from chronic hunger and malnutrition, 1/5 don't have physical access to water, and roughly 1.6 billion are facing economic water constraints (do not have the economic resources to access available water). Food and water insecurity are exacerbating the incidence and transmission of infectious disease.

At a time when investment is sorely needed, the Hill has been making dramatic cutbacks in foreign assistance and foreign investment is falling short. Efforts made by the private sector, philanthropy, and civil society, while valuable, remain siloed. Opportunties are being missed by not addressing the interrelated nature of food and health issues.

Despite this dire outlook, Naylor offered solutions to help us rethink our development strategy.

1. Invest in more diversified and nutritious crops that have more climate adaptation potential.
2. Consider new irrigation strategies, particularly in areas like Africa where 96% of the continent is still not irrigated. Not large dams, but small, distributed irrigation systems that rely on solar and wind.
3. Integrate food and health programs and the way we think about domestic and productive water uses.

Naylor was joined on the panel by Jeff Seabright (Vice President, The Coca-Cola Company), Daniel Gerstein (Deputy Under Secretary for Science and Technology, U.S. Department of Homeland Security), and Geoff Dabelko (Woodrow Wilson International Center for Scholars). The panel was moderated by Frank Sesno (George Washington University and Planet Forward). Video of the plenary can be found below: