One of the fastest-growing segments of livestock farming in the United States is aquaculture, according to Rosamond L. Naylor, a Stanford professor of environmental Earth system science and director of Stanford's Program on Food Security and the Environment. And like any other form of livestock, fish generate waste.

But just what happens to the waste produced by coastal aquaculture has largely been a matter of conjecture.

"For many years, people have assumed that because of the ocean's size, because of the energy in its currents, that any substance you introduced into the ocean would quickly be diluted into concentrations that were barely detectable," said Jeffrey R. Koseff, professor of civil and environmental engineering.

Now Koseff and Naylor, together with Oliver Fringer, assistant professor of civil and environmental engineering, and a team of colleagues, have developed a computational model that allows researchers to predict where the effluent from a coastal fish farm would go. The answer may not always be appealing to down-current swimmers and surfers.

"We discovered that the state of the natural environment around fish pens can dramatically affect how far waste plumes travel from the source," Koseff said. "This suggests that we should not simply assume 'dilution is the solution' for aquaculture pollution."

The simulation incorporates the influence of variables such as tides, currents, the rotation of the Earth and the physical structure of the pens in calculating the dispersal pattern of the waste.

"These plumes actually remain quite coherent at very long distances from the source and could become a major pollution problem in coastal regions," Koseff said.

Naylor and Koseff said the model should prove valuable in selecting appropriate sites for future fish farms. Knowing the amounts of feces and uneaten food that are generated by pens, researchers will be able to predict how that dissolved waste will travel from a particular location, given local conditions.

Fish pens off the coast of Greece. Aquaculture projects such as this are expected to play an increasing role in producing fish for consumption as wild fisheries decline, but dealing with the effluent from fish farms is an increasing concern.

Naylor said the model will likely show that some locations previously thought appropriate for fish farms are actually not suitable, but she doesn't think the aquaculture industry will necessarily see that as a bad thing. Having clearly defined boundaries of where aquaculture is acceptable will help the industry avoid conflict with other users of coastal waters.

"A lot of the industry people that I have talked to are not working against the environment, they are really trying to make aquaculture work, and this would provide a useful tool for them," Naylor said.

Naylor, Koseff and their colleagues will be publishing their findings in an upcoming issue of Environmental Fluid Mechanics. The paper is online now.

Naylor said their findings are quite timely, in light of legislation in the works at both the state and federal levels.

In 2006, California passed the Sustainable Oceans Act, aimed at protecting the biologically rich waters off the coast while also recognizing the importance and economic value of providing fresh seafood.

Naylor said that a draft of the regulations to implement that legislation is currently under review and this new modeling tool should help in setting guidelines for locating and monitoring aquaculture.

At the federal level, the National Oceanic and Atmospheric Administration is taking public comments through April 11 on a draft of a national aquaculture policy.

"After the bill is passed, rules and regulations will have to be written around it and what we are providing now is a tool to help with that," she said.

Koseff acknowledged that some people might balk at relying on a computer model to guide regulations.

"We understand and recognize the limitations of the simulations," he said. "But we have confidence that the physics that we are representing in the model are realistic and our results are very representative of what happens in a near-coastal environment."

Naylor said that for an aquaculture operation to be economically feasible, a lot of pens will likely have to be concentrated in one area, making waste a significant concern.

"I also work a lot in terrestrial livestock, and I think the dissolved wastes that come out are one of the worst aspects of intensive animal raising," she said.

"If we are really thinking about getting our animal protein from fish in the future, and it is coming from net pens that are in the ocean, one of the big fears is, are we going to have feedlots of the sea?

"We would really like to completely avoid the problems we have seen in terrestrial livestock. That would be the ultimate goal and this model can help achieve that."

Naylor is the director of Stanford's Program on Food Security and the Environment and a senior fellow at the university's Woods Institute for the Environment. Koseff is co-director of the Woods Institute and a senior fellow at the Freeman Spogli Institute for International Studies.

February 10th marked the launch of the Program on Food Security and the Environment's Global Food Policy and Food Security Symposium Series. Setting the stage for the two-year series were Jeff Raikes, CEO of the Bill & Melinda Gates Foundation, and Greg Page, CEO and Chairman of Cargill Inc. As CEOs from the largest foundation and the largest agricultural firm in the world they provided important perspectives on global food security in these particularly volatile times. Full video and clips of the event are now available - Improving Food Security in the 21st Century: What are the Roles for Firms and Foundations.

Jeff Raikes: A Perspective from the Bill & Melinda Gates Foundation

Catalytic philanthropy

The Gates Foundation, through its Agricultural Development Initiative, has been a leader in addressing global food security issues. The Foundation allocates 25% of its resources to global development and to addressing the needs of the 1 billion people who live in extreme poverty ($1/day). 70-75% of those people live in rural areas and are dependent on subsistence agriculture for their livelihoods.

The Gates Foundation is driven by the principle: how can it invest its resources in ways that can leverage performance and address market failures? Its approach embodies a novel concept driven by both private sector motives and public responsibilities. Raikes describes this as catalytic philanthropy.

"The Foundation identifies where its investments can create an innovation, a new intervention that can really raise the quality of lives for people," said Raikes. "If successful, it can be scaled up and sustained by the private sector if we can show that there is a profit opportunity or the public sector if we can show that this is a better way to improve the overall quality of society through investment in public dollars."

Image Photo credit: Michael Prince

In the realm of agriculture, allocating resources across the agricultural value chain has proven to be the most effective approach. As an example of this strategy, Raikes talked about a farmer-owned, Gates-supported dairy chilling plant in Kenya. The cooling facility provided the storage necessary to provide a predictable price at which to sell farmers' milk. This price knowledge and market access gave farmers the confidence to invest in better technology and better dairy cattle. The plant also provided artificial insemination services and extension services to teach farmers how to get greater amounts of milk from the cattle.

"I love the concept. I also love the numbers," said Raikes. "In just two or three years there were now 3,000 farmers in a 25 kilometer radius that were able to access this dairy chilling plant and able to sell their milk."

In addition to improving incomes, Raikes remarked that very consistently what he hears is when farmers are able to improve their incomes the first thing they do with the money is invest in the education of their children.

Upcoming challenges to food security

During the next 40 years or so, global food production must double to accommodate a growing and richer population. Climate change and water scarcity contribute to this challenge. The places that will suffer the most severe weather are also the places where the poorest farmers live. 95% of sub-Saharan agriculture is rain fed with very little irrigation.

"If we are going to be able to feed the world we are going to have to figure out how to achieve more crop per drop," cautioned Raikes. "This includes trying to breed crop varieties that will better withstand water shortages. Early results show that you can get as much as a 20% increase in yield or more under stressed conditions when you have varieties that are bred for that need."

These challenges are compounded by the current economic crisis that is putting pressure on budgets in both donor and developing countries. In 2009, the G20 committed 22 billion dollars to agricultural development in recognition of the importance of agricultural development to food security. However, of the 22 billion promised, 224 million dollars went to five countries in the first round of grants in June. By November, when 21 additional countries submitted their proposals, just 97 million dollars were available to be dispersed and 17 countries were turned away empty handed.

High- and low-tech solutions

In an effort to alleviate some of this deficit, the Gates Foundation has committed 300 million dollars in six grants that span the value chain. These include investments in science and technology, farm management practices, farmer productivity, and market access as well as the data and policy environment to support the Foundation's work. The grants are intended to support about 5 ½ million farm families in sub-Saharan Africa and South Asia.

"We believe innovative solutions can come from both high-tech and low-tech," said Raikes. "On the high-tech end, submergent genes are allowing rice crops to survive periods of flooding up to 15 days. In areas of rice farming prone to flooding, this can save entire crops traditionally wiped out by such weather disasters."

Image Photo credit IRRI/Ariel Javellana

The sub1gene seeds are now being used by 400,000 farmers and are on track to be used by 20 million rice farmers by 2017. On the low-tech end, the Gates Foundation is providing $2 triple layer bags to farmers to reduce crop loss from pests; an affordable solution that has increased average income per farmer by $150/year.

"We primarily support conventional breeding, but we also support biotechnology breeding. In some cases we think that breeders in Africa and South Asia will want to take advantage of the modern tools we use here in our country to provide better choices for their farmers," explained Raikes.

Reasons for optimism

After years of diminished support, US Agricultural Development assistance to sub-Saharan Africa has gone from about 650 million in 2005 to about 1.5 billion in 2009. In developing countries, the Comprehensive Agricultural Development Program (CADP) in Africa has challenged countries to dedicate 10% of their national budgets to agriculture with the goal of improving annual agricultural growth by 6%. 20 countries have signed on to the CADP compacts, and 10 countries are exceeding the 6% growth target. Finally, since 1990, 1.3 billion people worldwide have lifted themselves out of poverty primarily through improvements in agricultural productivity.

Raikes pointed to Ghana as a success story. Since 1990, casaba production, an important staple food for poor smallholder farmers, has increased fivefold. Tomato production increased six fold. The cocoa sector has been revived and hunger has been cut by 75%.

"The key to success in Ghana was a combination of getting the right developing country policy with the right macroeconomic reform, the right institutional reform, smart public investment, and an overall good policy environment," said Raikes.

Supporting good policy is an important part of the Foundation's food security strategy, and was a strong motivation behind its funding of FSE's Global Food Policy and Food Security Symposium series.

"We see this symposium series as an opportunity to gather policy leaders who will bring new ideas of what will be effective policy approaches and effective economic environments in the countries we care a lot about, in particular sub-Saharan Africa and South Asia," said Raikes.

Raikes concluded his remarks by reminding everyone that the key to improving food security globally is making sure women, who make up at least 70% of the farm labor population, are included in the equation.

Greg Page: Balancing the race to caloric sufficiency with rural sociology

As the largest global agricultural firm, Cargill has an influential role to play in the world of food and agriculture. Cargill is a major supplier of food and crops and a provider of farmer services, inputs, and market access.

Image Photo credit: Olaf Hammelburg

Together with the Gates Foundation, Cargill has reached out and trained 200,000 cocoa farmers in the Ivory Coast, Ghana, and Cameroon. One tribe and one small village at a time the company has helped improve food safety, quality maintenance, and storage; benefiting the farmers, Cargill, and customers further down the supply chain. Cargill has also assisted, through financing and product purchasing, 265,000 farmers in Benin, Burkina Faso, the Ivory Coast, Malawi, Uganda, Zambia, and Zimbabwe.

Can the world feed itself?

A billion people lack sufficient caloric intake on a daily basis. In sub-Saharan Africa, 38% of all children are chronically malnourished, largely the result of inadequate agricultural productivity. While nine of the ten countries that have the highest prevalence of malnourishment are in sub-Saharan Africa, the two countries with the largest absolute number of malnourished people are India and China.

"This points to the difficulty of this problem," said Page. "India exports corn and soybean protein and China has 2.5 trillion dollars of hard currency reserves. These issues aren't necessarily of ability to feed people, but a willingness and commitment to do so."

Can the world feed itself? Yes, said Page.

When you break down the number of calories needed per malnourished person per day and convert that to tons of whole grains required to extinguish that hunger you get 30 million tons; 1/6 the amount of grain we converted to fuel globally last year. In the U.S. alone, 40% of our corn goes to ethanol.

"It isn't an issue of caloric famine-it is an issue of economic famine," stated Page. "In other words, this is not a food supply problem, but rather the lack of purchasing power to pay for a diet. An adequate price must be assured to reward the farmer for his efforts and to provide enough money that she can do it again the following year."

Rural sociology premium

What we face is the need to keep smallholders on the farm-despite the fact that they may not be the low-cost producer of foodstuffs-in order to avoid a rural population migration that would be unsustainable. As a result, the challenge the world faces is who is going to pay that rural sociology premium? If it costs more to raise crops on small farms is that burden going to be borne by the urban poor or is there going to be an alternative funding mechanism that allows smallholders to succeed?

Image Photo credit: Cargill

What is the survival price for a smallholder farmer? Page explained that if you wanted a family of four on a farm in sub-Saharan Africa to receive an income commensurate with the average per capita income of the urban population, you would come up with a price near $400 a ton.

"To put this in context, the highest price for maize that has ever been reached here in the United States is about $275 a ton," said Page. "This rural sociology premium to sustain smallholders is not an insignificant amount of money. How do we achieve fairness between the revenue received by the rural smallholder and the price borne by the urban consumer?"

State of disequilibrium - complacency to crisis

Today we are experiencing incredible price volatility where commodity prices are in a continuous state of disequilibrium. Very small changes in production have outsized impacts on price. This is in contrast to the last two and a half decades when the world operated with fairly robust stocks due to crop subsidies in the United States and Western Europe.

"This period of subsidization was when the western world probably did more harm to sub-Saharan Africa and South Asia than any other period in history," said Page. "We refused to allow price to signal to western farmers to produce less. As a result, the world price of grains fell far below the ability of any smallholder to compete. We then shipped those surpluses to developing countries, which then failed to invest in their agriculture for decades."

Today we are lurching from complacency to crisis. The ability of information and market speculation to be transmitted rapidly is affecting purchasing decisions of thousands to millions of consumers. Rising fuel prices, export restrictions, increasing demand for crops for biofuels, and unpredictable weather have all contributed to higher prices. Some of the drivers of price, however, are good things, such as the increase in per capita income and the capacity of more people to have a more dense and nutritious diet.

"Interestingly, the upside of the ethanol and biofuels program is that it brought prices back to a sufficiency that reinvigorated investment in agriculture," noted Page. "On one level I think a very good argument could be made that the biofuels program brought the world further from famine than it ever had been because of the price."

Critical food security factors

Page concluded by summarizing the elements that Cargill believes are critically important to increase food security. The first is the ability to understand the tradeoffs between a fast path to caloric sufficiency and the needs of rural sociology. Second, that crops be grown in the right soil, with the right technology, and relying on free trade so we can harvest competitive advantage to its fullest.

Another critical factor is rural property rights. Smallholders must have the ability to own the land, have access to it, and transfer it to future generations if you want a farmer to reinvest in his farm, said Page.

"Smallholders in developing countries need some degree of revenue certainty and access to a reliable market if we expect them to do what their countries really need them to do, which is raise productivity," explained Page. "Today they are often forced to sell at harvest, often below the cost of production, and lack the storage capabilities and capital to provide crops sufficiently and continuously."

Open, trust-based markets also play a key role in ensuring food security. Governments need to support trade. When Russia, Ukraine, and Argentina turned to embargos as a way to protect domestic food prices open markets were jeopardized and price volatility increased. Finally, there are very important roles for the world's governments in the creation of infrastructure that is vital to provide access to markets.

"I believe fully and completely in the world's capacity to harvest photosynthesis to feed every single person and to do it at prices that can be borne by all," concluded Page.

In an effort to foster a more open, transparent and accessible scientific dialogue, we've started a new effort aimed at inspiring pioneering use of technology, new media and computational thinking in the communication of science to diverse audiences. Initially, we'll focus on communicating the science on climate change.

We're kicking off this effort by naming 21 Google Science Communications Fellows. These fellows were elected from a pool of applicants of early to mid-career Ph.D. scientists nominated by leaders in climate change research and science-based institutions across the U.S. It was hard to choose just 21 fellows from such an impressive pool of scientists; ultimately, we chose scientists who had the strongest potential to become excellent communicators. That meant previous training in science communication; research in topics related to understanding or managing climate change; and experience experimenting with innovative approaches or technology tools for science communication.

This year's fellows are an impressive bunch:

• Brendan Bohannan, Associate Professor of Environmental Studies and Biology, University of Oregon
• Edward Brook, Professor, Department of Geosciences, Oregon State University
• Julia Cole, Professor, Department of Geosciences, University of Arizona
• Eugene Cordero, Associate Professor, Meteorology and Climate Science, San Jose University
• Frank Davis, Professor, Landscape Ecology & Conservation Planning, University of California-Santa Barbara
• Andrew Dessler, Professor, Atmospheric Sciences, Texas A&M University
• Noah Diffenbaugh, Assistant Professor, Environmental Earth System Science, Stanford University
• Simon Donner, Assistant Professor, University of British Columbia
• Nicole Heller, Research Scientist, Climate Central
• Brian Helmuth, Professor, Biological Sciences, University South Carolina
• Paul Higgins, Associate Director, Policy Program, American Meteorological Society
• Jonathan Koomey, Consulting Professor, Civil and Environmental Engineering, Stanford University
• David Lea, Professor, Earth Science, University of California-Santa Barbara
• Kelly Levin, Senior Research Associate, World Resources Institute
• David Lobell, Assistant Professor, Environmental Earth System Science, Stanford University
• Edwin Maurer, Associate Professor, Civil Engineering, Santa Clara University
• Susanne Moser, Research Associate, Institute of Marine Sciences, University of California-Santa Cruz
• Matthew Nisbet, Associate Professor, School of Communication, American University
• Rebecca Shaw, Director of Conservation, The Nature Conservancy, CA Chapter
• Whendee Silver, Professor, Ecosystem Ecology and Biogeochemistry, University of California-Berkeley
• Alan Townsend, Professor, Ecology and Evolutionary Biology, University of Colorado

At our Mountain View, Calif. headquarters in June, the fellows will participate in a workshop, which will integrate hands-on training and facilitated brainstorming on topics of technology and science communication. Following the workshop, fellows will be given the opportunity to apply for grants to put their ideas into practice. Those with the most impactful projects will be given the opportunity to join a Lindblad Expeditions & National Geographic trip to the Arctic, the Galapagos or Antarctica as a science communicator.

Congratulations to all of the fellows! And we'll keep you posted on more ideas and tools emerging for science communication.

A team of researchers from Stanford University, the Carnegie Institution for Science, and Arizona State University has found that converting large swaths of land to bioenergy crops could have a wide range of effects on regional climate.

In an effort to help wean itself off fossil fuels, the U.S. has mandated significant increases in renewable fuels, with more than one-third of the domestic corn harvest to be used for conversion to ethanol by 2018. But concerns about effects of corn ethanol on food prices and deforestation had led to research suggesting that ethanol be derived from perennial crops, like the giant grasses Miscanthus and switchgrass. Nearly all of this research, though, has focused on the effects of ethanol on carbon dioxide emissions, which drive global warming.

"Almost all of the work performed to date has focused on the carbon effects," said Matei Georgescu, a climate modeler working in ASU's Center for Environmental Fluid Dynamics. "We've tried to expand our perspective to look at a more complete picture.  What we've shown is that it's not all about greenhouse gases, and that modifying the landscape can be just as important."

Georgescu and his colleagues report their findings in the current issue (Feb. 28, 2011) of the Proceedings of the National Academy of Sciences (see Direct Climate Effects of Perennial Bioenergy Crops in the United States). Co-authors are David Lobell of Stanford University's Program on Food Security and the Environment and Christopher B. Field of the Carnegie Institution for Science, also located in Stanford, California.

In their study, the researchers simulated an entire growing season with a state-of-the-art regional climate model. They ran two sets of experiments - one with an annual crop representation over the central U.S. and one with an extended growing season to represent perennial grasses. In the model, the perennial plants pumped more water from the soil to the atmosphere, leading to large local cooling. 

"We've shown that planting perennial bioenergy crops can lower surface temperatures by about a degree Celsius locally, averaged over the entire growing season. That's a pretty big effect, enough to dominate any effects of carbon savings on the regional climate." said Lobell.

The primary physical process at work is based on greater evapotranspiration (combination of evaporated water from the soil surface and plant canopy and transpired water from within the soil) for perennial crops compared to annual crops. 

"More study is needed to understand the long-term implication for regional water balance." Georgescu said. "This study focused on temperature, but the more general point is that simply assessing the impacts on carbon and greenhouse gases overlooks important features that we cannot ignore if we want a bioenergy path that is sustainable over the long haul."

David Lobell will be giving two talks this week at the AGU fall meeting:

Towards accurate models of global crop-climate interactions

This talk will provide a brief overview of the major links between climate and crops that are most in need of representation in global models. The talk will then focus on one of the key links - the effect of climate variation on crop productivity across a range of cropping systems and regions. I will present some recent work to use historical datasets to build statistical models at the scale of individual countries. The effects of different datasets and modeling assumption will be explored, to identify areas where statistical models provide robust representation of crop responses to climate. A sample application of these models - estimating the net regional and global impacts of recent trends in climate - will be presented.

Assessing the future of crop yield variability in the United States with downscaled climate projections

One aspect of climate change of particular concern to farmers and food markets is the potential for increased year-to-year variability in crop yields. Recent episodes of food price increases following the Australian drought or Russian heat wave have heightened this concern. Downscaled climate projections that properly capture the magnitude of daily and interannual variability of weather can be useful for projecting future yield variability. Here we examine the potential magnitude and cause of changes in variability of corn yields in the United States up to 2050. Using downscaled climate projections from multiple models, we estimate a distribution of changes in mean and variability of growing season average temperature and precipitation. These projections are then fed into a model of maize yield that explicitly factors in the effect of extremely warm days. Changes in yield variability can result from a shift in mean temperatures coupled with a nonlinear crop response, a shift in climate variability, or a combination of the two. The results are decomposed into these different causes, with implications for future research to reduce uncertainties in projections of future yield variability.

FSE director Rosamond L. Naylor is among a talented group of advisors in Spain for the annual meeting of the Advisory Committee of the Pew Fellows Program in Marine Conservation. The Advisory Committee of the Pew Fellows Program in Marine Conservation featured in the photograph above from left to right:

• Ellen Pikitch, Executive Director of the Institute for Ocean Conservation Science, School of Marine and Atmospheric Sciences, Stony Brook University
  
• Michael Lodge, Legal Counsel, International Seabed Authority, Jamaica
  
• Meryl Williams, Director, Fish-Watch Asia Pacific, Australia
  
• Larry Crowder, Professor of Marine Biology, Duke University
  
• Stephen Roady (kneeling), Attorney, Earthjustice, Washington DC
  
• Callum Roberts, Professor of Marine Conservation, University of York, UK
  
• Peter Tyedmers, School for Resource and Environmental Studies, Dalhousie University, Halifax, Nova Scotia, Canada
  
• Pablo Marquet, Professor of Ecology, Catholic University, Chile

FSE Center Fellow David Lobell was among three recipients of the Macelwane Medal honored for significant contributions to the geophysical sciences by an outstanding young scientist (less than 36 years of age). Established in 1961, the Macelwane Medal is awarded annually by the American Geophysical Union.

The Macelwane Medal was renamed in 1986 in honor of former AGU president James B. Macelwane (1953-1956). Renowned for his contributions to geophysics, Macelwane was deeply interested in teaching and encouraging young scientists. The Macelwane Medal is awarded annually to as many as three or, under exceptional circumstances, up to five individuals "for significant contributions to the geophysical sciences by an outstanding young scientist (less than 36 years of age)." Nominees must be less than 36 years of age on 1 January of the year of presentation. James N. Brune was the first recipient of this medal.

James B. Macelwane was a seismologist at Saint Louis University. During the 1920s and 1930s, working with students and colleagues, he used seismic P waves to derive early velocity models of the mantle, developed travel time curves for numerous seismic phases, developed methods for hypocentral determinations of deep earthquakes, and showed that 4 to 10 s microseisms are traveling waves originating from storms at sea. Macelwane was a leader in establishing seismology on a firm theoretical basis. His textbook, Introduction to Theoretical Seismology, was published in 1936.