Narco-Deforestation Accelerates Loss of Biodiversity

In Central America, drug policies become conservation policies. The Central American isthmus exploded into prominence as a drug trafficking corridor in 2006, when pressure on Mexican cartels pushed smuggling operations to the south and into the remote forest frontiers of Honduras, Guatemala, and Nicaragua. Since then, vigorous interdiction programs have pushed traffickers into ever more remote zones, back and forth from country to country, bringing money, manpower, and greater opportunities for deforestation.Kendra McSweeney of the Department of Geography at Ohio State University and co-workers dug into the recent comprehensive report by the Organization of American States (OAS), titled The Drug Problem in the Americas, and wrote up their findings in a recent contribution to Science’s Policy Forum. They found that “mounting evidence suggests that the trafficking …

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Europe’s oldest footprints uncovered on English coast

The earliest human footprints outside of Africa have been uncovered, on the English coast, by a team of scientists led by Queen Mary University of London, the British Museum and the Natural History Museum.Up to five people left the series of footprints in mud on the bank of an ancient river estuary over 800,000 years ago at Happisburgh in northeast Norfolk.Dr Simon Lewis from Queen Mary’s School of Geography has been helping to piece together the geological puzzle surrounding the discovery — made in May 2013 — which is evidence of the first known humans in northern Europe.Dr Lewis’s research into the geology of the site has provided vital information on the sediments in which the prints were found. “My role is to work out the sequence of deposits at the site and how they were laid down. This means I can provide a geological context for the archaeological evidence of human occupation at the site.”The importance of the Happisburgh footprints is highlighted by the rarity of footprints surviving elsewhere. Only those at Laetoli in Tanzania at about 3.5 million years and at Ileret and Koobi Fora in Kenya at about 1.5 million years are older.A lecturer in physical geography, and co-director of the Happisburgh project (http://www.ahobproject.org/), Dr Lewis added that the chance of encountering footprints such as this was extremely rare; they survived environmental change and the passage of time.Timing was also crucial as “their location was revealed just at a moment when researchers were there to see it” during a geophysical survey. “Just two weeks later the tide would have eroded the footprints away.””At first we weren’t sure what we were seeing,” explains Dr Nick Ashton of the British Museum “but as we removed any remaining beach sand and sponged off the seawater, it was clear that the hollows resembled prints, and that we needed to record the surface as quickly as possible.”Over the next two weeks researchers used photogrammetry, a technique that can stitch together digital photographs to create a permanent record and 3D images of the surface. It was the analysis of these images that confirmed that the elongated hollows were indeed ancient human footprints.In some cases the heel, arch and even toes could be identified, equating to modern shoes of up to UK size 8. While it is not possible to tell what the makers of these footprints were doing at the time, analysis has suggested that the prints were made from a mix of adults and children.Their discovery offers researchers an insight into the migration of pre-historic people hundreds of thousands of years ago when Britain was linked by land to continental Europe.At this time, deer, bison, mammoth, hippo and rhino grazed the river valley at Happisburgh. The land provided a rich array of resources for the early humans with edible plant tubers, seaweed and shellfish nearby, while the grazing herds would have provided meat through hunting or scavenging.During the past 10 years the sediments at Happisburgh have revealed a series of sites with stone tools and fossil bones; this discovery is from the same deposits.The findings are published in the science journal PLOS ONE.The work at Happisburgh forms part of a new major exhibition at the Natural History Museum Britain: One Million Years of the Human Story opening on February 13.Story Source:The above story is based on materials provided by Queen Mary University of London. Note: Materials may be edited for content and length.

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World ocean systems undermined by climate change by 2100

Oct. 15, 2013 — An ambitious new study describes the full chain of events by which ocean biogeochemical changes triggered by humanmade greenhouse gas emissions may cascade through marine habitats and organisms, penetrating to the deep ocean and eventually influencing humans.Previous analyses have focused mainly on ocean warming and acidification, considerably underestimating the biological and social consequences of climate change. Factoring in predictable synergistic changes such as the depletion of dissolved oxygen in seawater and a decline in productivity of ocean ecosystems, the new study shows that no corner of the world ocean will be untouched by climate change by 2100.”When you look at the world ocean, there are few places that will be free of changes; most will suffer the simultaneous effects of warming, acidification, and reductions in oxygen and productivity,” said lead author Camilo Mora, assistant professor at the Department of Geography in the College of Social Sciences at the University of Hawai’i at Mānoa (UH Mānoa). “The consequences of these co-occurring changes are massive — everything from species survival, to abundance, to range size, to body size, to species richness, to ecosystem functioning are affected by changes in ocean biogeochemistry.”The human ramifications of these changes are likely to be massive and disruptive. Food chains, fishing, and tourism could all be impacted. The study shows that some 470 to 870 million of the world’s poorest people rely on the ocean for food, jobs, and revenues, and live in countries where ocean goods and services could be compromised by multiple ocean biogeochemical changes.Mora and Craig Smith with UH Mānoa’s School of Ocean and Earth Science and Technology (SOEST) worked with a 28-person international collaboration of climate modelers, biogeochemists, oceanographers, and social scientists to develop the study, which is due for publication October 15 in the scientific journal PLOS Biology.The researchers used the most recent and robust models of projected climate change developed for the Fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) to inform their analysis. They quantified the extent of co-occurrence of changes in temperature, pH, oxygen, and primary productivity based on two scenarios: a business-as-usual scenario wherein atmospheric CO2 concentrations could reach 900 ppm by 2100, and an alternative scenario under which concentrations only reach 550 ppm by 2100 (representing a concerted, rapid CO2 mitigation effort, beginning today).They discovered that most of the world’s ocean surface will be simultaneously impacted by varying intensities of ocean warming, acidification, oxygen depletion, or shortfalls in productivity. Only a very small fraction of the oceans, mostly in polar regions, will face the opposing effects of increases in oxygen or productivity, and nowhere will there be cooling or pH increase.”Even the seemingly positive changes at high latitudes are not necessary beneficial. Invasive species have been immigrating to these areas due to changing ocean conditions and will threaten the local species and the humans who depend on them,” said co-author Chih-Lin Wei, a postdoctoral fellow at Ocean Science Centre, Memorial University of Newfoundland, Canada.The researchers assembled global distribution maps of 32 marine habitats and biodiversity hotspots to assess their potential vulnerability to the changes. As a final step, they used available data on human dependency on ocean goods and services and social adaptability to estimate the vulnerability of coastal populations to the projected ocean biogeochemical changes.”Other studies have looked at small-scale impacts, but this is the first time that we’ve been able to look the entire world ocean and how co-occurring stressors will differentially impact the earth’s diverse habitats and people,” said co-author Andrew Thurber, a postdoctoral fellow at Oregon State University. …

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Effects of climate change on West Nile virus

Sep. 9, 2013 — The varied influence of climate change on temperature and precipitation may have an equally wide-ranging effect on the spread of West Nile virus, suggesting that public health efforts to control the virus will need to take a local rather than global perspective, according to a study published this week in the scientific journal Proceedings of the National Academy of Sciences.University of Arizona researchers Cory Morin and Andrew Comrie developed a climate-driven mosquito population model to simulate the abundance across the southern United States of one type of mosquito known to carry and spread West Nile virus to humans. They found that, under the future climate conditions predicted by climate change models, many locations will see a lengthening of the mosquito season but shrinking summer mosquito populations due to hotter and dryer conditions allowing fewer larvae to survive.However, these changes vary significantly depending on temperature and precipitation. For example, drops in summer mosquito populations are expected to be significant in the South, but not further north where there will still be enough rain to maintain summer breeding habitats and extreme temperatures are less common. These findings suggest that disease transmission studies and programs designed to control populations of disease-carrying mosquitoes must be targeted locally to maximize their effectiveness, the authors argue.”It used to be an open question whether climate change is going to make disease-carrying mosquitoes more abundant, and the answer is it will depend on the time and the location,” said Morin, who did the study as part of his doctoral dissertation in the lab of Comrie, UA provost and professor in the UA’s School of Geography and Development. Morin is now a postdoctoral researcher on Comrie’s team.”One assumption was that with rising temperatures, mosquitoes would thrive across the board,” Morin said. “Our study shows this is unlikely. Rather, the effects of climate change are different depending on the region and because of that, the response of West Nile virus transmitting mosquito populations will be different as well.””The mosquito species we study is subtropical, and at warmer temperatures the larvae develop faster,” Morin explained. “However, there is a limit — if temperatures climb over that limit, mortality increases. Temperature, precipitation or both can limit the populations, depending on local conditions.”In the southwestern U.S. …

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Extreme wildfires in Western U.S. likely fueled by climate change

Aug. 1, 2013 — Climate change is likely fueling the larger and more destructive wildfires that are scorching vast areas of the American West, according to new research led by Michigan State University scientists.These erratic fires are harder to contain and often result in catastrophic damage and loss of property and life. Although not analyzed in the study, the recent Arizona wildfire that began with a lightning strike and killed 19 firefighters appeared to be such an unpredictable, fast-spreading blaze, according to a state report.The MSU-led study, which appears in the Journal of Applied Meteorology and Climatology, predicts the trend will continue in the western United States.”Our findings suggest that future lower atmospheric conditions may favor larger and more extreme wildfires, posing an additional challenge to fire and forest management,” said Lifeng Luo, MSU assistant professor of geography and lead author on the study.The researchers analyzed current and future climate patterns projected by multiple regional climate models and their effect on the spread of fire in a mountainous region that includes Arizona, Idaho, Nevada, New Mexico, Utah and Wyoming. The study focused on August, the most active month for wildfires in the western United States.August 2012 saw 3.6 million acres burn in the region, the most of any August since 2000. However, there were only 6,948 fires in August 2012 — the second fewest in that 12-year timeframe — meaning the fires were much larger.Large wildfires are mainly driven by natural factors including the availability of fuel (vegetation), precipitation, wind and the location of lightning strikes. In particular, the researchers found that exceptionally dry and unstable conditions in the earth’s lower atmosphere will continue contributing to “erratic and extreme fire behavior.””Global climate change may have a significant impact on these factors, thus affecting potential wildfire activity across many parts of the world,” the study says.Co-authors include Ying Tang and Shiyuan Zhong from MSU, and Xindu Bian and Warren Heilman from the USDA Forest Service.

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