When it comes to climate change and its impacts on agriculture, we may know less than we think.

But according to David Lobell, Assistant Professor in Stanford’s Department of Environmental Earth System Science, acknowledging the gaps in our understanding could help us to more effectively prepare the world’s food system for a warmer future.

Lobell, who has built an impressive career around the study of climate change and its implications for global food security, addressed the topic of agricultural adaptation during a two-hour symposium held on the Stanford campus in early December. His presentation summarized the strengths and weaknesses of climate models in the context of global agriculture, and suggested broad strategies for preparing agriculture for climate change’s inevitable impacts.

Lobell began his talk by reaffirming some common beliefs. The Earth as a whole is unquestionably warming, he said. Precipitation intensity is increasing in high-rainfall areas, and the world’s driest regions are becoming drier.

“Think about the hottest day we currently experience in a 20-year period,” Lobell told listeners. “By mid-century, we’ll be seeing that hottest day every year, as opposed to every 20 years.” During the same period, soil moisture content in many of the world’s major agricultural areas will decrease by as much as 10 to 15 percent, while annual precipitation at the equator and high latitudes will increase by several inches per year.

At the global scale, Lobell said, climate change will have a net negative impact on existing agricultural systems. The world’s rainfed farms will become increasingly vulnerable to heat and water stress.  Growing ranges and seasons for heat-intolerant crops, such as wheat and sorghum, will contract. Although the high latitudes may see some gains from warmer temperatures and CO2 fertilization of certain crops, low-latitude regions – including South Asia and much of Africa – will suffer disproportionate yield losses as temperatures rise.

However, Lobell said that impacts aimed at local and national scales, as opposed to broad regions or the world as a whole, are much more difficult to predict. A moderate change in average rainfall across a continent could translate to drastic increases or decreases in individual countries. For example, while climate models suggest that Africa’s annual rainfall will change by less than 10 percent over the next 50 years, model projections show rainfall in the nation of Sengal changing by anywhere from five to 40 percent over the same period.

Additionally, Lobell said, forecasts of increasing climate variability are frequently overstated. “The number one misperception I hear is that climate change is going to mean more variability,” he noted.  In fact, model projections of year-to-year variability in temperature and precipitation cover a wide range. Some models do show large increases in variability over the next century – but others show a slight decrease.

Because we understand climate impacts best at the long-term and global scales, Lobell said, global responses that address long-term trends are the most likely to serve our future needs. He cautioned against approaches that prepare farmers for short-term variability, such as sudden floods or droughts, but fail to acknowledging the effects of steadily rising average temperatures. He also stressed the value of globally coordinated efforts, particularly those aimed at developing better heat and drought-tolerant crop varieties, to supplement local infrastructure projects.

 “We’re in a world where local resilience depends on global systems,” Lobell noted. He said that the interconnectedness of modern global food markets makes global trends, and global responses, increasingly relevant for local food security.

At both local and global levels, an effective response to climate change will require robust social institutions. Dr. Fatima Denton, Program Leader for Climate Change Adaptation in Africa for the Consultative Group on International Agricultural research, stressed this point in her comments on Lobell’s presentation. “Climate change has really unmasked our governance challenges and the weaknesses in our institutions,” Denton said. “This is not just about biophysical processes…it’s about the development pathways that we choose.”

Lobell agreed. Climate change, he said, presents “an important opportunity for transformation.” He encouraged present and future leaders to think critically about all aspects of the relevant science and policy. “Be skeptical of what you hear,” he advised, “and educate yourself about what we do and don’t know.”

This was the sixth talk in FSE's Global Food Policy and Food Security Symposium Series.

Stanford’s Center on Food Security and the Environment (FSE) has received a $2 million grant from Cargill, a second gift from the company that raises its total contribution to FSE to $5 million over 10 years.

The announcement was made Nov. 10 at a dinner celebrating the launch of FSE as a full-scale research center. FSE has more than doubled in size in five years. Because of its growth and increasing importance of food security issues at Stanford and worldwide, it became an official center in September.

“The center’s rapid growth would not have been possible without the generous support of Cargill,” FSE Director and William Wrigley Senior Fellow Rosamond L. Naylor said. “Cargill’s initial investment provided seed-funding for the bold, new research and teaching that was happening at FSE while keeping our lights on and the staff running during our critical years of early development.”

A $3 million grant from Cargill in 2008 jump-started a visiting fellows program at FSE and helped build the infrastructure to support the center’s research.

The new grant will continue to provide program support, but will also be used to hire younger faculty and scholars to Stanford to work within the new Center.

Stanford-Cargill partnership

Stanford's partnership with Cargill extends back to 1976 when Cargill endowed Walter P. Falcon, then Director of Stanford's Food Research Institute and now FSE Deputy Director, with the Helen C. Farnsworth Professorship in International Agricultural Policy. The gift was intended to strengthen Stanford's work in agricultural policy, specifically as it relates to the international grain economy. FSI senior fellow Scott Rozelle now holds the Helen C. Farnsworth chair.

FSE and Cargill remain committed to helping feed a growing population while preserving the planet's natural resources. FSE is an applied group focused on providing real solutions to important food and agricultural issues.

“Poverty is the main issue driving food insecurity—it’s a question of access rather than food availability,” Naylor said.

FSE’s partnership with Cargill has demonstrated how Stanford-based research can be relevant to the private sector. FSE is conducting ongoing research on oil palm and land use issues in Indonesia that is helping inform and shape policy. Work on aquaculture feeds in China is another overlapping area of interest, as are ongoing assessments of biofuels in the U.S., Africa and Asia. Both have a stake in better understanding climate change impacts on agriculture and food commodity price volatility.

“It is clear to us at FSE—and increasingly to leadership of Stanford—that global food security will remain a critical issue within international policy circles,” said Naylor. “With support like the grant from Cargill, we are confident that Stanford can play a leading role in shaping the future policy discourse.”

Blaming leaders in America and abroad for not doing enough to combat climate change, former United Nations Secretary-General Kofi Annan said continued failure to tackle the problem will result in worldwide hunger, social unrest and political turmoil.

“Without action at the global level to address climate change, we will see farmers across Africa – and in many other parts of the world including here in America – forced to leave their land,” the 2001 Nobel Peace Prize winner told a crowd of about 1,400 people at Stanford’s Memorial Auditorium on Thursday. “The result will be mass migration, growing food shortages, loss of social cohesion and even political instability.”

Citing numbers from the World Bank, Annan said rapidly rising food prices since 2010 have “pushed an additional 70 million people into extreme poverty.” He called a lack of food security for nearly 1 billion of the world’s population “an unconscionable moral failing” that is also a stumbling block to a strong international economy.

“It affects everything from the health of an unborn child to economic growth,” he said.

Annan’s talk, “Food Security Is a Global Challenge,” was delivered as part of a daylong conference on global underdevelopment sponsored by Stanford’s Freeman Spogli Institute for International Studies. The event drew the world’s leading experts in the field and featured panel discussions that explored the connections between global security and food supplies, health care and governance. Keynote speeches were delivered by Annan and Jeff Raikes, CEO of the Bill & Melinda Gates Foundation. Former Secretary of Defense Robert Gates also planned to deliver a talk to a private audience.

The conference marked the launch of FSI’s Center on Food Security and the Environment.

“With this facility, and the creative thinkers and inquisitive minds for which Stanford is famous, you are well-equipped to undertake research which advances our knowledge and helps to shape our response to the many global challenges we face,” Annan said. “And with the resources at your disposal, you also have the capacity to actively engage to influence policy, implement solutions and thus improve the lives of the most vulnerable people on the planet.”

Annan also lauded government initiatives such as America’s Feed the Future program that focus on alleviating global hunger. He recently met with Secretary of State Hillary Clinton, Secretary of Agriculture Tom Vilsack and Raj Shah, head of the U.S. Agency for International Development, to discuss ways to address food insecurity.

“If we pool our efforts and resources, we can finally break the back of this problem,” he said.

But he challenged wealthier nations to do more than pay lip service to the problem.

“We need to make sure that promises of extra support from richer countries are kept and involve fresh funds rather than the repackaging of existing financial commitments,” he said.

Annan, who is the chair of the Kofi Annan Foundation, the Africa Progress Panel, and the Alliance for a Green Revolution in Africa, said Africa represents both the greatest problem and the greatest promise when it comes to food security.

The continent is home to 60 percent of the world’s uncultivated arable land, but cannot produce enough food to feed its own people, he said. But if Africa can grow just half the world’s average yield of staple crops like wheat, corn and rice, it would end up with a food surplus.

Transforming Africa into one of the world’s biggest crop producers will take more than supporting farmers, he said. It entails sound environmental stewardship.

 “I hope this is an area where the Center on Food Security and the Environment can make a major contribution to finding solutions,” Annan said.

Without those solutions, the future is bleak.

In Sub-Saharan Africa, where global warming brings the threat of persistent drought, current crop production is expected to be cut in half by the end of the century and 8 percent of the region’s fertile land is expected to dry up.

“Those arguing, here and elsewhere, for urgent action and a focus on opportunities to green our economies still find themselves drowned out by those with short-term and vested interests,” Annan said. “This lack of long-term collective vision and leadership is inexcusable. It has global repercussions, and it will be those least responsible for climate change – the poorest and most vulnerable – that will pay the highest price.”

Annan's speech was sponsored by FSI, Stanford in Government and the Stanford University Speakers Bureau.

Over much of the world, the growing season of 2050 will probably be warmer than the hottest of recent years, with more variable rainfall. If we continue to grow the same crops in the same way, climate change will contribute to yield declines in many places. With potentially less food to feed more people, we have no choice but to adapt agriculture to the new conditions.

To some extent, adaptation can be done by moving crops to more favourable areas and by agronomic tweaks. But that will almost certainly not be enough. We will have to give crops a genetic helping hand, infusing them with new genes to allow them to better cope with new climates, and the new pests and diseases they will bring. Where are these genes going to come from?

Some of them could come from completely unrelated organisms, to be spliced into their new genomic homes using advanced biotechnologies. However, there is significant public resistance to that strategy, and it is still unclear how effective genetically modified crops are at coping with heat and drought. We cannot risk putting all our eggs in that basket.

Another source of genes for crop improvement are traditional heirloom varieties, often called landraces, which are still grown by subsistence farmers in many parts of the world, although they are fast disappearing. Large collections of their seeds have been made over the years, creating genebanks that are scoured by plant breeders searching for crop diversity, and which helped spur the Green Revolution in agriculture from the late 1960s.

But there’s a limit to the diversity found in domesticated species, imposed by domestication itself. Cultivated species usually contain a fraction of the genetic diversity found in their closest wild relatives — a legacy of the ‘domestication bottleneck’. Ancient farmers selected relatively few plants from the progenitors of modern crops, in a limited number of places. Although there has been continuous gene flow between crops and their wild relatives where they coexist, a lot of genetic diversity has been lost as agriculture has developed.

We know that the ‘lost’ genetic diversity includes genes for resistance to high temperatures and drought, and to pests and diseases, as well as taste and nutritional composition, and even yield. If there was ever a time to go back and reclaim this diversity, that time is now. In fact, it is already being used more than many people realize. For instance, there is probably no widely grown rice cultivar that does not have some genes obtained by breeders from its wild relatives. But we could be making much more effective, and systematic, use of the reservoir of diversity our Neolithic ancestors left behind.

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