Hurricanes And Global Warming, Science Looks For Answers
Researchers are homing in on the hurricane-prone Gulf of Mexico and Caribbean Sea to assess the likely changes, between now and the middle of the century, in the frequency, intensity, and tracks of these powerful storms. Initial results are expected early next year.
The National Center for Atmospheric Research (NCAR) in Boulder, Colo., working with federal agencies as well as the insurance and energy industries, has launched an intensive study to examine how global warming will influence hurricanes in the next few decades.
The goal of the project is to provide information to coastal communities, offshore drilling operations, and other interests that could be affected by changes in hurricanes.
“This science builds on years of previous investment,” said Cliff Jacobs, program director in the National Science Foundation (NSF)’s Division of Atmospheric Sciences, which is funding the project. “The outcome of this research will shed light on the relationship between global warming and hurricanes, and will better inform decisions by government and industry.”
The project relies on an innovative combination of global climate and regional weather models, run on one of the world’s most powerful supercomputers.
“It’s clear from the impacts of recent hurricane activity that we urgently need to learn more about how hurricane intensity and behavior may respond to a warming climate,” says NCAR scientist Greg Holland, who is leading the project. “The increasingly dense development along our coastlines and our dependence on oil from the Gulf of Mexico leaves our society dangerously vulnerable to hurricanes.”
The new study follows two major reports, by the U.S. Climate Change Science Program (CCSP) and Intergovernmental Panel on Climate Change (IPCC), that found evidence for a link between global warming and increased hurricane activity.
But many questions remain about future hurricane activity. For example, the CCSP report concluded that future changes in frequency were uncertain, and that rainfall and intensity were likely to increase, but with unknown consequences.
Improved understanding of climate change and hurricanes is an especially high priority for the energy industry, which has a concentration of drilling platforms, refineries, pipelines and other infrastructure in the region that are vulnerable to severe weather.
Hurricanes Gustav and Ike damaged offshore oil production and several refineries, disrupting gasoline supplies.
The project is part of a larger effort examining regional climate change between 1995 and 2055.
The simulations are being run on NCAR’s bluefire supercomputer with support from NSF, NCAR’s sponsor, and through a long-term collaboration with the insurance industry through the Willis Research Network.
“This research program by NCAR is a major contribution to the insurance industry and public policy makers,” says Rowan Douglas, managing director of Willis.
“The primary way to improve our understanding of present and future hurricane risk is to generate computer simulations of storms in unprecedented detail.”
For the project, the model will examine three decades in detail: 1995-2005, 2020-2030, and 2045-2055. Scientists will use statistical techniques to fill in the gaps between these decades.
A major goal is to examine how several decades of greenhouse-gas buildup could affect regional climate and, in turn, influence hurricanes and other critical weather features. Scientists will also investigate the impact of the powerful storms on global climate.
One of the most difficult technical challenges for such a project is to create a model that can capture both the climate of the entire world and the behavior of a single hurricane.
To get around this roadblock, NCAR has developed an approach called Nested Regional Climate Modeling (NRCM). The center “nests” a special version of its high-resolution weather model (the Weather Research and Forecasting model, or WRF) inside its lower-resolution, global climate model (the Community Climate System Model, or CCSM).
The resulting simulations show fine-scale detail for certain regions, like the Gulf of Mexico, while also incorporating global climate patterns.
For each of its decade-long time slices, the NRCM’s resolution will be about 20 miles across Africa, Europe, and the South Atlantic, 7.5 miles across the tropical Atlantic and northeastern United States, and an even sharper 2.5 miles over the Caribbean and Gulf of Mexico, southeastern United States, and drought-prone western United States.
“Combining weather and climate models in this way enables more detailed projections of hurricanes in a warming world than any study to date,” says Holland. “These projections will help reduce the uncertainty of current assessments, and they also serve the very important role of providing experience about applying future predictions of changes to high impact weather systems in general.”
Smoking And Global Warming More Related Than You Think
Yea so there you go…
Can Farmed Fish Save The Worlds Oceans?
Nearly half of the seafood we eat today is farmed. And while aquaculture is often equated with pollution, habitat degradation, and health risks, this explosive growth in fish farming may in fact be the most hopeful trend in the world’s increasingly troubled food system, according to a new report by Worldwatch Institute.
In Farming Fish for the Future, Senior Researcher Brian Halweil illustrates how, if properly guided, fish farming can not only help feed an expanding global population, but also play a role in healing marine ecosystems battered by overfishing.
“In a world where fresh water and grain supplies are increasingly scarce, raising seafood like oysters, clams, catfish, and tilapia is many times more efficient than factory-farmed chicken or beef,” says Halweil. “Farmed fish can be a critical way to add to the global diet to hedge against potential crop losses or shortages in the supply of meat.”
“But not all fish farming is created equal,” Halweil notes. Carnivorous species like salmon and shrimp, while increasingly popular, consume several times their weight in fish feed—derived from other, typically smaller, fish—as they provide in edible seafood. “It generally requires 20 kilograms of feed to produce just 1 kilogram of tuna,” Halweil says. “So even as we depend more on farmed fish, a growing scarcity of fish feed may jeopardize future expansion of the industry.”
Poorly run fish farms can generate coastal pollution in the form of excess feed and manure, and escaped fish and disease originating on farms can devastate wild fisheries. For example, a fish farm with 200,000 salmon releases nutrients and fecal matter roughly equivalent to the raw sewage generated by 20,000 to 60,000 people. Scotland’s salmon aquaculture industry is estimated to produce the same amount of nitrogen waste as the untreated sewage of 3.2 million people—just over half the country’s population.
Cramped facilities can also create ill health for fish, costing producers millions of dollars in disease prevention and foregone revenues. In recent years, shrimp farmers in China have lost $120 million to bacterial fish diseases and $420 million to shrimp diseases.
Fish farming has expanded to meet the soaring global demand for seafood. On average, each person on the planet is eating four times as much seafood as was consumed in 1950. The average per-capita consumption of farmed seafood has increased nearly 1,000 percent since 1970, in contrast to per-capita meat consumption, which grew just 60 percent.
In 2006, fish farmers raised nearly 70 million tons of seafood worth more than $80 billion—nearly double the volume of a decade earlier. Experts predict that farmed seafood will grow an additional 70 percent by 2030.
How can fish farming be made more sustainable? Innovative industry practices are key, but a shift toward sustainable fish farming will also require a fundamental change in public attitudes. This includes a willingness to prioritize fish that are lower on the food chain, such as shellfish and tilapia. But can consumers today be mobilized to shift the aquaculture industry in the same way they pressured tuna fleets to adopt more dolphin-friendly practices in the 1980s?
The need for more sustainable fish farming is critical, according to the report. Farmed seafood provides 42 percent of the world’s seafood supply, and is on target to exceed half in the next decade, yet there are no widely accepted standards for what constitutes “good” fish farming. By comparison, the organic food industry has strong international and national standards, even though it constitutes just 3 to 5 percent of the world’s food supply.
This points to a greater role for aquaculture certification and standards in the coming years, Halweil says. Efforts currently under way seek to model the effective labeling systems that exist in other areas of agriculture, such as for wild-caught fish, heritage breeds of livestock, and organic and local foods.
“The last wild ingredient in our diet is no longer completely wild,” says Halweil. “This doesn’t have to be a permanent situation, since wild fish stocks can recover. But as more coastal ecosystems are transformed into sites for fish pens, cages, and cultured seaweeds, fish farmers and the food industry will need to make ecological restoration as much a goal as meeting the growing demand for seafood.”
Ecological Aquaculture
Ecological aquaculture, or “integrated multitrophic aquaculture,” involves designing farms to function more like healthy aquatic ecosystems. Generally, fish farms produce waste and pollute surrounding waters because of the high concentration and limited mobility of the fish. These factors also leave the fish more susceptible to disease. However, farms that integrate complementary species can greatly reduce pollution and disease levels. Cooke Aquaculture’s salmon farm in Back Bay, Canada, takes advantage of a natural ecosystem cleansing service provided by blue mussels and kelp. The shellfish filter excess waste from the fish cages, while the seaweed thrives on dissolved nutrients in the water.
Farming in the Warehouse
At the Center for Marine Biotechnology in Baltimore, Maryland, researchers are using city-supplied water and a complex filtration system to raise a few hundred fish completely indoors. Raising fish in a closed pen, either in a warehouse or floating on the ocean, avoids the common pitfalls of modern fish farming: net pens pollute coastal environments with waste and antibiotics, fish escapes threaten the diversity of wild populations, and diseases can spread easily. The Center’s operation is the first indoor marine aquaculture system that can re-circulate nearly all of its water and expel zero waste.
Cleaning Wastewater
If managed correctly, fish farms can go beyond addressing the problems caused by the industry itself and provide a net positive impact on the environment. Traditional ponds outside of Calcutta, India, called bheris, produce some 13,000 tons of fish a year for the city’s 12 million inhabitants, and serve as critical bird habitat. But the bigger environmental service they provide is that the fish feed on the 600 million liters of raw sewage that spews from Calcutta daily, turning a health risk into a key urban crop.
Restoring Habitats
Fish farming can help to restore degraded coral reefs and wetlands. The metal cages that hold farmed shellfish often function as artificial reefs around which striped bass, shad, and other marine species congregate. In the Caribbean, the Caicos Conch Farm raises King conch not just to sell to restaurants around the world, but to help re-seed coral reefs with this keystone species.
Eating Local Seafood
People who eat from their local waters have a natural reason to be concerned about what goes into them. The Southold Program in Aquaculture Training (SPAT) on Long Island, New York, helps volunteers raise baby shellfish in floating cages to restore the local scallop economy. Participants receive training in algae growth, marine ecology, and shellfish dynamics, and also get to eat half their harvest of fresh, mature shellfish. In turn, they report changing their daily habits that affect water quality, such as shunning chemical fertilizers, upgrading home septic systems, and using nontoxic paint on their boats.
Eating Little Fish to Save Big Ones
In Peru, massive schools of the tiny Peruvian anchovy are netted each year. Although the fish is chock-full of the same beneficial fatty acids that have made tuna, salmon, and other big fish famous for warding off heart disease and boosting brain development, nearly all of the anchovy catch is turned into fishmeal and fish oil, used to fatten pigs and chickens on factory farms worldwide. To address this problem, students at the University of Lima have launched a campaign to change the image of the anchoveta from something that only poor people eat into a tasty dish for well-heeled sophisticates.
Beetles Get By With A Little Help From Their Friends
Southern pine beetles colonize pine trees and lay eggs in galleries within the tree bark. They line these galleries with spores of a beneficial fungus and a bacterium. Inadvertently, they can also bring along parasitic mites and spores of an antagonistic (competitor) fungus. The antagonist fungus competes to colonize the tree, but carries no nutritional value for the larvae. As the beneficial bacterium spreads, it produces an antibiotic that inhibits growth of the antagonistic fungus.
Humans living in communities often rely on friends to help get what they need and, according to researchers in the lab of Cameron Currie at the University of Wisconsin-Madison, many microbes, plants and animals benefit from ‘friendly’ associations too.
The Currie team’s study, which was funded by the National Science Foundation (NSF) and published in the Oct. 3, 2008, issue of the journal Science, describes the complex relationship between a beetle, two types of tree fungus and a bacterium that aids in their struggle to survive and thrive.
Research in the Currie lab revealed that adult beetles have a specialized compartment in their bodies used to store two other organisms: a slow-growing beneficial fungus that serves as a food source and a bacterium that produces a unique, newly discovered antibiotic. Interestingly, the antibiotic inhibits the growth of a fast-growing competitor fungus but does not affect the slow-growing beneficial fungus.
Before laying eggs in tree bark, adult female beetles spread the slow-growing, beneficial fungus and bacteria around the area where they will deposit the eggs. The antibiotic from the bacteria prevents growth of the fast-growing competitor fungus but does not harm the slow-growing beneficial fungus, which continues to grow and provide a rich source of nutrition for the developing beetle larvae.
Adult southern pine beetle in flight.
“There are perhaps 10 million species of insects on the planet,” says Currie, an evolutionary biologist. “So, if insects associate with bacteria like this more generally, then there’s potentially a huge number of new places to explore.”
NSF Program Officer Lita Proctor agrees, saying this research, which was co-authored by Jon Clardy of Harvard Medical School, has important implications for the ecosystems these species occupy.
“It may be that some organisms evolved symbioses (cooperative relationships) as a strategy to give them an advantage over others when competing for resources,” said Proctor. “These cooperative relationships may be much more common than we thought.”
In-depth study of these interactions could also lead to identification of new types of antibiotics or other chemicals which may have agricultural or medicinal uses. Thus in the future, we may get by with help from our little friends.
Southern pine beetle larva in a gallery, another name for the place where the beetles lay their eggs. Within the gallery, which is prepared by an adult female, you can see a "lawn" of filamentous microbes. On the left is the fungus found inside the tree bark (red circle). The larva feeds on this fungus. Between the fungus and the larva is another filamentous organism, which is the bacteria (black square).
Old School Ice Shows Us Hints Of The Future
Ancient Gas Trapped In Ice
In recent years, public discussion of climate change has included concerns that increased levels of carbon dioxide will contribute to global warming, which in turn may change the circulation in the earth’s oceans, with potentially disastrous consequences.
In a paper published today in the journal Science, researchers presented new data from their analysis of ice core samples and ocean deposits dating as far back as 90,000 years ago and suggest that warming, carbon dioxide levels and ocean currents are tightly inter-related. These findings provide scientists with more data and insights into how these phenomena were connected in the past and may lead to a better understanding of future climate trends.
With support from the National Science Foundation, Jinho Ahn and Edward Brook, both geoscientists at Oregon State University, analyzed 390 ice core samples taken from Antarctic ice at Byrd Station. The samples offered a snap shot of the Earth’s atmosphere and climate dating back between 20,000 and 90,000 years. Sections of the samples were carefully crushed, releasing gases from bubbles that were frozen within the ice through the millennia. These ancient gas samples were then analyzed to measure the levels of carbon dioxide contained in each one.
Ahn and Brook then compared the carbon dioxide levels from the ice samples with climate data from Greenland and Antarctica that reflected the approximate temperatures when the gases were trapped and with ocean sediments in Chile and the Iberian Peninsula. Data from the sediments provided the scientists with an understanding of how fast or slow the ocean currents were in the North Atlantic and how well the Southern Ocean was stratified during these same time periods.
The researchers discovered that elevations in carbon dioxide levels were related to subsequent increases in the Earth’s temperature as well as reduced circulation of ocean currents in the North Atlantic. The data also suggests that carbon dioxide levels increased along with the weakening of mixing of waters in the Southern Ocean. This, the researchers say, may point to potential future scenario where global warming causes changes in ocean currents which in turn causes more carbon dioxide to enter the atmosphere, adding more greenhouse gas to an already warming climate.
Ahn and Brook state that a variety of factors may be at work in the future that alter the relationship between climate change and ocean currents. One potential factor is that the levels of carbon dioxide in today’s atmosphere are much higher than they were during the period Ahn and Brook studied. The researchers hope that future studies of the ancient gas from a newly drilled ice core may allow a higher resolution analysis and yield more details about the timing between CO2 levels and the temperature at the earth’s poles.
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