In this paper we discuss the scope of the adaptation challenge facing world agriculture in the coming decades. Due to rising temperatures throughout the tropics, pressures for adaptation will be greatest in some of the poorest parts of the world where the adaptive capacity is least abundant. We discuss both autonomous (market driven) and planned adaptations, distinguishing: (a) those that can be undertaken with existing technology, (b) those that involve development of new technologies, and (c) those that involve institutional/market and policy reforms. The paper then proceeds to identify which of these adaptations are currently modeled in integrated assessment studies and related analyses at global scale. This, in turn, gives rise to recommendations about how these models should be modified in order to more effectively capture climate change adaptation in the farm and food sector. In general, we find that existing integrated assessment models are better suited to analyzing adaptation by relatively well-endowed producers operating in market-integrated, developed countries. They likely understate climate impacts on agriculture in developing countries, while overstating the potential adaptations. This is troubling, since the need for adaptation will be greatest amongst the lower income producers in the poorest tropical countries. This is also where policies and public investments are likely to have the highest payoff. We conclude with a discussion of opportunities for improving the empirical foundations of integrated assessment modeling with an emphasis on the poorest countries.
Stanford researchers working with the U.S. Navy’s Marine Mammal Program in San Diego have discovered a startling variety of newly-recognized bacteria living inside the highly trained dolphins that the Navy uses to protect its ships and submarines, find submerged sea mines and detect underwater intruders. They found similar types of bacteria in wild dolphins as well.
“About three quarters of the bacterial species we found in the dolphins’ mouths are completely new to us,” said David Relman, Stanford professor of microbiology and medicine, and co-author of a paper published in the journal Nature Communications on Wednesday.
A U.S. Navy dolphin opens its mouth for a swab to collect bacterial samples.
These previously unknown bacteria represent “whole new realms of life,” according to Relman.
“Bacteria are among the most well-studied microbes, so it was surprising to discover the degree to which the kinds of bacteria we found were types that have never been described,” he said. “What novelty means is not just new names of species, families, classes or phyla…there’s reason to believe that along with this taxonomic novelty, there’s functional novelty.”
The U.S. Navy has been training dolphins and sea lions to carry out defensive military missions from their bases in San Diego and elsewhere since the early 1960s.
Over the years, it has also funded scientific research and become the single largest contributor to the scientific literature on marine mammals, producing more than 800 publications, according to the Navy.
Relman started working with the Navy more than 15 years ago to identify bacteria suspected of causing stomach ulcers in their dolphins.
His latest project to catalog the bacterial communities (or microbiota) living inside the dolphins began when the Navy asked him to help develop a probiotic bacterial strain that could keep their dolphins healthy, or help sick dolphins get better.
Navy trainers took regular swabs from the dolphins’ mouths and rectal areas, using what looked like a Q-tip, and shipped the samples to Stanford on dry ice for analysis.
Stanford researchers analyzed oral, rectal and gastric samples from the U.S. Navy's dolphins and sea lions, as well as samples from the dolphins' blowholes and the surrounding water.
They also collected samples of the air the dolphins exhaled from their blowholes (known as “chuff”) onto sterile filter paper, as well as samples of their gastric juices using a tube that the dolphins would swallow on command, and for comparison, bacteria from the surrounding water.
The study found a similar amount of diversity and novelty in bacterial samples taken from wild dolphins living in Sarasota Bay off the west coast of Florida, although there were slight differences in the bacteria from the dolphins’ mouths.
Relman said he hoped to develop a profile of the normal microbial communities in healthy dolphins and other marine mammals, so that scientists could detect any early change that might signify an imminent disease, or health problems caused by climate change and ocean warming.
“There’s a lot of concern about the changing conditions of the oceans and what the impact could be on the health of wild marine mammals,” Relman said. “We would love to be able to develop a diagnostic test that would tell us when marine mammals are beginning to suffer from the ill effects of a change in their environment.”
The research could help solve other mysteries, such as how dolphins digest their food, even though they swallow fish whole without chewing them.
The key could be a unique bacterial group that’s also been identified in an endangered species of freshwater dolphins living in China’s Yangtze River, said Elisabeth Bik, a research associate at the Stanford Department of Medicine and lead author on the paper.
“It’s a very intriguing bacterial group that nobody has seen before in any other terrestrial animal group,” said Bik. “I would really love to know more about those bacteria and sequence their genomes to understand more about their functional capacity.”
Zak, a 375-pound California sea lion, shows his teeth during a training swim. Zak has been trained to locate swimmers near piers, ships, and other objects in the water considered suspicious and a possible threat to military forces in the area.
The study also examined oral, gastric and rectal samples from the Navy’s trained sea lions.
“The sea lions and dolphins are kept at the same facility, they’re fed exactly the same fish, and they’re swimming in the same water…but they’re very, very different in terms of microbiota,” Bik said.
Unlike dolphins, sea lions share many common types of bacteria with their terrestrial cousins.
“Sea lions weren’t that different from other carnivores like dogs and cats,” Bik said. “They’re evolutionarily related to them, and their microbiota looks very similar to those animals. But dolphins don’t really have a terrestrial mammal that’s closely related, and their microbiota looks very different from anything else that people have seen.”
Relman said his team was planning on expanding their study to include other marine mammals such as sea otters, killer whales, baleen whales, grey whales, harbor seals, elephant seals and manatees. Their purpose, in part, is to understand how life in the sea, over the millions of years since the return of mammals, may have shaped the structure of their microbial communities and the roles they play in marine mammal health.
They’re already working to analyze more than 80 samples of killer whale stool that the U.S. National Oceanic and Atmospheric Administration has gathered with the help of specially trained sniffer dogs, which stand on the bow of their boats and point to fresh killer whale feces before it sinks.
The California Department of Fish and Wildlife is contributing samples from the sea otters and seals it studies as part of its conservation, ecological, and monitoring programs.
And the Marine Mammal Center in Sausalito, which is the West Coast’s largest rescue and rehabilitation facility for marine mammals, is sending samples from the seals in its care.
Relman said the research could help scientists begin to answer fundamental questions about life in the ocean.
“Marine mammals remain one of the more poorly understood habitats for studying microbial life, and there would be lots of reasons for thinking that these are important environments to study, in part because of the relevance for the health of these marine mammals, but also because they represent a view into what it means to live in the sea and the nature of our relationship with this vast aspect of our environment,” Relman said.
Collaborators and co-authors on this study included Stephanie Venn-Watson and Kevin Carlin from the National Marine Mammal Foundation, and Eric Jensen from the Space and Naval Warfare Systems Center Pacific, in San Diego.
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A U.S. Navy dolphin opens its mouth for a swab to collect bacterial samples.
Growing knowledge that the climate is changing has far outpaced our knowledge of how these changes might impact economic outcomes that we care about. Does climate change constitute one of the most important development challenges facing humanity over the next century, as is sometimes claimed, or is it a minor concern relative to other determinants of economic prosperity? Our proposed work will use modern econometric techniques and new data to quantify how poverty has responded to historical shifts in
We assess the benefits of climate change mitigation for global maize and wheat production over the 21st century by comparing outcomes under RCP4.5 and RCP8.5 as simulated by two large initial condition ensembles from NCAR’s Community Earth System Model. We use models of the relation between climate variables, CO2 concentrations, and yields built on observations and then project this relation on the basis of simulated future temperature and precipitation and CO2 trajectories under the two scenarios, for short (2021–2040), medium (2041–2060) and long (2061–2080) time horizons. We focus on projected mean yield impacts, chances of significant slowdowns in yield, and exposure to damaging heat during critical periods of the growing seasons, the last of which is not explicitly considered in yield impacts by most models, including ours. We find that substantial benefits from mitigation would be achieved throughout the 21st century for maize, in terms of reducing (1) the size of average yield impacts, with mean losses for maize under RCP8.5 reduced under RCP4.5 by about 25 %, 40 % and 50 % as the time horizon lengthens over the 21st century; (2) the risk of major slowdowns over a 10 or 20 year period, with maize chances under RCP4.5 being reduced up to ~75 % by the end of the century compared to those estimated under RCP8.5; and (3) exposure to critical or “lethal” heat extremes, with the number of extremely hot days under RCP8.5 roughly triple current levels by end of century, compared to a doubling for RCP4.5. For wheat, we project small or occasionally negative effects of mitigation for projected yields, because of stronger CO2 fertilization effects than in maize, but substantial benefits of mitigation remain in terms of exposure to extremely high temperatures.
The world remains perilously close to a nuclear disaster or catastrophic climate change that could devastate humanity, according to Stanford experts and California Governor Jerry Brown, who were on hand to unveil the latest update to the Bulletin of Atomic Scientists’ “doomsday clock” on Tuesday.
The symbolic clock was created in 1947 when Albert Einstein and Robert Oppenheimer (the father of the U.S. nuclear program) founded the publication.
The closer the minute hand gets to midnight, the closer their Board of Science and Security predicts humankind is to destroying itself.
“I must say with utter dismay that it stays at three minutes to midnight,” said Rachel Bronson, the publication’s executive director and publisher, in a bi-coastal teleconference carried live from The National Press Club in Washington D.C. and the Stanford campus.
Despite some positive development over the past year, such as the Iran nuclear deal and the Paris climate accords, the doomsday clock is now the closest it’s been to midnight since the peak of Cold War hostilities in the mid 1980s.
Stanford experts, including former U.S. Secretary of Defense William J. Perry and former Secretary of State George P. Shultz, said they agreed with the dire assessment.
“The danger of a nuclear catastrophe today, in my judgment, is greater than it was during the Cold War…and yet our policies simply do not reflect those dangers,” said Perry, who is a faculty member at Stanford’s Center for International Security and Cooperation.
Perry said he was especially concerned that the U.S. and Russia were engaged in new arms race, with both countries working to rapidly modernize their nuclear arsenals.
“Whatever we need to do for deterrence, it does not require rebuilding what we did during the Cold War era,” he said.
Perry urged President Barack Obama not to give up on the goal of nuclear disarmament during his last year in office, and to push for a breakthrough deal to control fissile material at the upcoming Nuclear Summit in Washington D.C.
“These summit meetings have been quite significant, and if he can use this last summit meeting to establish international standards for fissile control, which fifty heads of state sign up to, that would be a real achievement,” Perry said.
Shultz said the U.S. needed to offer a new version of the bold plans and decisive actions that legendary American statesmen George Marshall and Dean Acheson pursued after World War II.
“We have to be engaged, because when we don’t give leadership, nobody does,” said Shultz, a distinguished fellow at the Hoover Institution.
The doomsday clock was initially designed to communicate the threat from nuclear weapons, but has since been expanded to include cyber and biosecurity and the dangers of unsustainable climate change.
California Governor Jerry Brown described climate change as a “daunting threat,” with many similarities to nuclear dangers.
“Climate change and nuclear accident or nuclear war or nuclear sabotage or nuclear terrorism, they’re tied together,” Brown said.
“Climate change is moving slowly, but tipping points are around the corner and you don’t know when you’ve reached one, and beyond a tipping point, we may not be able to come back.”
Brown said he was dismayed at the lack of political action to address climate change and nuclear threats.
“I’ve been around politics all my life, and I can see an obviously broken process, a democratic system that has turned more into spectacle than getting the job done,” Brown said.
“In order to have the political leaders deal with this, they have to first acknowledge it.”
When a high school student in the audience asked what he could personally do to tackle the threat of nuclear weapons, Perry said the most important step was to educate himself about the issues, so he could educate others.
“If you can get ten people interested in talking about this problem, and each of those ten can get ten people interested in talking about this problem, it builds up in a geometric progression,” Perry said.
“I think once the public understands the dangers, they will galvanize our Congress and our leaders into action.”
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Former U.S. Secretary of Defense William J. Perry (center) speaks at a press conference announcing the Bulletin of Atomic Scientists' latest "doomsday clock" estimates, as former U.S. Secretary of State George P. Shultz (left) and California Governor Jerry Brown (right) look on.
Abstract: The Federal response to dual use pathogens is being actively debated. We are at a critical juncture between free science exploration and government policy. Should science be regulated? We impede discovery and innovation at our peril. Yet, this issue must be viewed through the lens of the looming infectious disease threat, globalization and its consequences, and environmental challenges such as climate change.
About the Speaker: Lucy Shapiro is a Professor in the Department of Developmental Biology at Stanford University School of Medicine where she holds the Virginia and D. K. Ludwig Chair in Cancer Research and is the Director of Stanford’s Beckman Center for Molecular & Genetic Medicine. She is a member of the scientific advisory boards of the Ludwig Institute for Cancer Research, the Pasteur Institute in Paris, and the Lawrence Berkeley National Labs and is a member of the Board of Directors of Pacific Biosciences, Inc. She founded the anti-infectives discovery company, Anacor Pharmaceuticals, that was recently sold to Pfizer. She has co-founded a second company, Boragen LLC, providing novel antifungals for agriculture and the environment. Her studies of the control of the bacterial cell cycle and the establishment of cell fate has yielded fundamental insights into the living cell and garnered her multiple awards including the International Canadian Gairdner Award, the Abbott Lifetime Achievement Award, the Selman Waksman Award and the Horwitz Prize. In 2013 President Obama awarded her the US National Medal of Science. She is an elected member of the US National Academy of Sciences, the National Academy of Medicine, and the American Academy of Arts & Sciences.
Lucy Shapiro
Professor, Department of Developmental Biology, School of Medicine
Stanford University
Quantitative estimates of the impacts of climate change on economic outcomes are important for public policy. We show that the vast majority of estimates fail to account for well-established uncertainty in future temperature and rainfall changes, leading to potentially misleading projections. We reexamine seven well-cited studies and show that accounting for climate uncertainty leads to a much larger range of projected climate impacts and a greater likelihood of worst-case outcomes, an important policy parameter. Incorporating climate uncertainty into future economic impact assessments will be critical for providing the best possible information on potential impacts.
We review the emerging literature on climate and conflict. We consider multiple types of human conflict, including both interpersonal conflict, such as assault and murder, and intergroup conflict, including riots and civil war. We discuss key methodological issues in estimating causal relationships and largely focus on natural experiments that exploit variation in climate over time. Using a hierarchical meta-analysis that allows us to both estimate the mean effect and quantify the degree of variability across 55 studies, we find that deviations from moderate temperatures and precipitation patterns systematically increase conflict risk. Contemporaneous temperature has the largest average impact, with each 1σ increase in temperature increasing interpersonal conflict by 2.4% and intergroup conflict by 11.3%. We conclude by highlighting research priorities, including a better understanding of the mechanisms linking climate to conflict, societies’ ability to adapt to climatic changes, and the likely impacts of future global warming.
Growing evidence demonstrates that climatic conditions can have a profound impact on the functioning of modern human societies, but effects on economic activity appear inconsistent. Fundamental productive elements of modern economies, such as workers and crops, exhibit highly non-linear responses to local temperature even in wealthy countries. In contrast, aggregate macroeconomic productivity of entire wealthy countries is reported not to respond to temperature= while poor countries respond only linearly. Resolving this conflict between micro and macro observations is critical to understanding the role of wealth in coupled human–natural systems and to anticipating the global impact of climate change. Here we unify these seemingly contradictory results by accounting for non-linearity at the macro scale. We show that overall economic productivity is non-linear in temperature for all countries, with productivity peaking at an annual average temperature of 13 °C and declining strongly at higher temperatures. The relationship is globally generalizable, unchanged since 1960, and apparent for agricultural and non-agricultural activity in both rich and poor countries. These results provide the first evidence that economic activity in all regions is coupled to the global climate and establish a new empirical foundation for modelling economic loss in response to climate change, with important implications. If future adaptation mimics past adaptation, unmitigated warming is expected to reshape the global economy by reducing average global incomes roughly 23% by 2100 and widening global income inequality, relative to scenarios without climate change. In contrast to prior estimates, expected global losses are approximately linear in global mean temperature, with median losses many times larger than leading models indicate.
A U.S. Navy dolphin opens its mouth for a swab to collect bacterial samples.
Stanford researchers analyzed oral, rectal and gastric samples from the U.S. Navy's dolphins and sea lions, as well as samples from the dolphins' blowholes and the surrounding water.
Zak, a 375-pound California sea lion, shows his teeth during a training swim. Zak has been trained to locate swimmers near piers, ships, and other objects in the water considered suspicious and a possible threat to military forces in the area.
