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.

"The challenges Seoul faces in the coming years will be how to balance its military alliance with the United States and its economic partnership with China," suggested Gi-Wook Shin, director of the Stanford Korean Studies Program, in a recent interview with the Korea Times. Shin suggested the idea for involving universities more in regional diplomacy discussions, and he briefly described his new research project which explores an alternative approach for South Korean diplomacy.

On Friday, April 1, Stanford University hosted twelve North Korean officials making an unprecedented economic tour of the United States. Organized by Professor Susan Shirk of the University of California Institute on Global Conflict and Cooperation, the two-week tour of American businesses and academic institutions was an opportunity for the visitors to see firsthand what improved relations with the United States might mean in terms of economic cooperation.

The North Koreans included senior and mid-level officials responsible for economic, trade, financial and foreign affairs. Their visit took place despite the lack of diplomatic relations between the United States and the Democratic People's Republic of Korea (DPRK) and the continuing U.S. and UN sanctions against the country for its development of nuclear weapons and long-range missiles.

Welcoming the visitors to a luncheon in Encina Hall, David Straub, associate director of the Korea Program at the Walter H. Shorenstein Asia-Pacific Research Center (Shorenstein APARC), briefed them on the Freeman Spogli Institute for International Studies at Stanford University (FSI) and its research centers, including Shorenstein APARC and the Center for International Security and Cooperation (CISAC). Straub also introduced representatives from FSI and the School of Medicine who have been involved in policy, academic, and humanitarian engagement projects with the DPRK.

Mr. Henry S. Rowen, co-director of the Stanford Program on Regions of Innovation and Entrepreneurship (SPRIE), then outlined the history and organization of Stanford University and its leading role in the development of Silicon Valley. Mr. John Sandelin, senior associate emeritus of the Stanford Office of Technology Licensing, described the university's policies on sharing university-generated intellectual property with the private sector. Following the presentations, American guests at the luncheon, including CISAC's Dr. William J. Perry and Dr. Siegfried S. Hecker, had informal discussions with their North Korean tablemates about the possibilities of, and obstacles to, economic collaboration between the two countries.

The North Koreans' visit to Stanford concluded with a stop at the Hoover Tower observation deck for a panoramic view of the Stanford campus, where they were able to see how Stanford graduates had developed Silicon Valley literally around the campus. DPRK delegation members expressed appreciation for the hospitality they were shown at Stanford and underlined their hopes for economic exchanges with the United States.

The most recent previous visit to Stanford by a DPRK delegation took place in January 2008, when CISAC Professor John W. Lewis, Shorenstein APARC director Gi-Wook Shin, and the School of Medicine's Dr. Sharon Perry hosted five public health officials for discussions about collaboration on tuberculosis control. Out of that visit evolved Stanford's DPRK Tuberculosis Project, which, in association with the DPRK Ministry of Public Health and NGO partners, is developing the country's first laboratory with the capacity to diagnose drug-resistant tuberculosis.

Japan's massive earthquake and tsunami three weeks ago and the challenging recovery process continue to make news headlines around the world. It is difficult to separate fact and reasonable speculation about the future from the terror-filled coverage about radiation leaking from the Fukushima nuclear complex. In an effort to make sense of recent events, the Walter H. Shorenstein Asia-Pacific Research Center (Shorenstein APARC) convened a panel of experts for a discussion about the possible future implications arising from this complex and emotionally charged situation for Japan's energy policy, economy, and politics.

Addressing an audience of one hundred students, faculty, and members of the general public on March 30, Shorenstein APARC associate director for research Daniel C. Sneider expressed the center's deep sympathy for those affected by the natural disasters and its profound admiration for the way in which the people of Japan are dealing with the aftermath. Members of the panel echoed these sentiments throughout the event.

Michio Harada, Deputy Counsel General at the Consulate General of Japan in San Francisco, cited official government figures indicating that, as of March 28, twenty-eight thousand people were dead or missing and one-hundred-and-eighty thousand people were still in evacuation shelters. Faced with such staggering figures, Japan remains in a rescue and recovery phase, he said, but is receiving a tremendous amount of global support. More than one hundred and thirty countries have provided financial assistance, and eighteen countries and regions have sent rescue teams. Collective public spirit is currently very strong, Deputy Counsel Harada emphasized. Japan's challenge moving forward, he suggested, will be to adopt pragmatic measures to fund reconstruction projects in the areas destroyed or damaged by the natural disasters.

Understanding the situation at the Fukushima nuclear power facility and the information circulating about the potential health risks of radiation exposure is complicated, stressed Siegfried S. Hecker, co-director of the Center for International Security and Cooperation. He described the intricate design and structure of the reactors and outlined the sequence of events up to the present, explaining the immediate, crucial challenge of continuing to cool the reactors and deal with the leakage of radiation from them. While there are definite and potentially very serious health threats from radiation exposure and contamination, Hecker said, fear and stress about the situation could also negatively affect mental and physical wellbeing. It is too soon to know the long-term implications for energy policy in Japan and other countries, he suggested, emphasizing the significance of learning from this experience in order to improve any future use of nuclear power.

Robert Eberhart, a researcher with the Stanford Program on Regions of Innovation and Entrepreneurship, proposed that the global supply chain is flexible enough to absorb any manufacturing disruptions in Japan. He noted that in the past twenty years most of Japan's heavy manufacturing has moved overseas, and that the components made there are a comparatively less significant part of the supply chain. In terms of the overall impact on Japan's economy, Eberhart suggested that the net effect on the GDP would be neutral over the next two years, explaining that the imminent loss of business and investment in some areas would be offset by the growth of firms involved in the reconstruction process.

Phillip Lipscy, a center fellow at the Freeman Spogli Institute for International Studies and an assistant professor with the Department of Political Science, stated that events and immediate needs during the early stages of reconstruction may have long-term affects on policymaking and the government structure in Japan. For example, the continued use of nuclear energy—a relatively clean and efficient source of power accounting for 30 percent of Japan's total energy consumption—will face public opposition due to rising concerns about safety and pressing energy needs. In addition, while Prime Minister Naoto Kan's prompt response after the natural disasters helped boost popular sentiment for him and the Democratic Party of Japan (DPJ), how they fare in the long term—especially with regard to the DPJ's relationship with the opposition Liberal Democratic Party and reconstruction-related modifications to its key economic policies—remains to be seen, Lipscy said.

Sneider closed the event with a comparison between the events in Japan and the April 2010 Gulf of Mexico oil spill, pointing to criticism that the Obama and Kan administrations have received for not regulating large corporations closely enough. A prompt resolution to the dangerous—and contentious—situation at the Fukushima nuclear complex is the most immediate concern, and one that will help foretell the long-term political implications for Japan's government, he concluded.

Although there is still a long road ahead in Japan—especially until the accident at Fukushima's nuclear reactor is contained and the actual after-effects of radiation are better understood—the underlying message during the panel discussion was that Japan will indeed recover and that the terrible events of the past weeks have brought people—and even the competing political parties—closer together.