• The ohia tree is in trouble

    The Ê»ohiÊ»a is Hawaii’s iconic tree, a keystone species that maintains healthy watersheds and provides habitat for numerous endangered birds. But a virulent fungal disease, possibly related to a warmer, drier climate, is now felling the island’s cherished `ohi`a forests.

    Hawaii’s isolation, 2,390 miles from the North American mainland, has given the island chain a unique array of species found nowhere else, including the Ê»ohiÊ»a lehua, an evergreen in the myrtle family with delicate pom-pom-shaped flowers composed of clusters of showy stamens in a range of hues from red and orange to pale yellow. In 2010, homeowners on the Big Island of Hawaii began reporting that Ê»ohiÊ»a in their upland rainforest were dying without apparent cause. Researchers named the mysterious condition “Rapid Ê»OhiÊ»a Death” (ROD). 

    On Google Earth, you can see the telltale brown streaks in the Puna forest reserve, Hawaii's largest remaining upland rainforest located on the slope of Kilauea volcano, where many Ê»ohiÊ»a lehua (Metrosideros polymorpha) trees have already succumbed. If you scroll over 60 miles to the west to the other side of the island, the green canopy behind Kealakekua Bay on the Kona coast — where Captain James Cook first set foot on Hawaii and was later killed — is pocked with the bleached skeletons of dead and dying trees. 

    Scenes like these have become commonplace in the American West, where several conifer species, weakened by long-term drought and warmer temperatures, have been decimated by bark beetles. Researchers are wondering if climate change may also have stressed Ê»ohiÊ»a trees, perhaps helping to trigger the current outbreak on Hawaii. 

    The fungus clogs the vascular system of the trees, making them wilt and die as if from a drought.

    An overall decrease in trade winds has created drier conditions in recent years in parts of the islands, at the same time that rising temperatures have warmed things up in the cool upland forests where Ê»ohiÊ»a thrive. 

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  • Do you live in one of America's worst cities for air pollution?

    The American Lung Association has released its annual “State of the Air” report and its findings are troubling. Most Americans live in counties with air pollution so bad that it is a severe risk to their health. According to the report, that means 166 million people are at risk of an early death and significant health problems including asthma, developmental damage and cancer.

    Without a doubt the most concerning discovery made by the American Lung Association was that short-term particle pollution had increased sharply since last year’s report: “Short-term spikes” of particle pollution hit record levels in seven of the 25 most polluted U.S. cities in this period.

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  • Australian river on fire with fracked coal seam gas

    So much methane is bubbling into a river surrounded by hundreds of fracking wells that it's a fire hazard! Local campaigners blame the coal seam gas industry for the gas releases which are spreading along Queensland's river Condamine and gaining in intensity.

    So much methane gas is now bubbling up through the Condamine River in Queensland, Australia that it exploded with fire and held a large flame.

    Gas seeping into the river began shortly after coal seam gas operations started nearby and is growing in volume and the stretch of river affected is expanding in length.

     

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  • VW agrees to buy back or "fix" 500,000 cars in North America

    With only days to go before the deadline, Volkswagen AG (VW) and the U.S. government reached a partial settlement over how to deal with the automaker’s “dieselgate” emissions scandal.

    Volkswagen agreed to fix or buy back some 500,000 vehicles caught up in the crisis. What wasn’t agreed upon is how much the company should pay in fines and compensation to consumers affected by the crisis.

     

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  • USGS study shows why some chemicals bio-accumulate and others don't

    Researchers have figured out what makes certain chemicals accumulate to toxic levels in aquatic food webs. And, scientists have developed a screening technique to determine which chemicals pose the greatest risk to the environment.

    According to the study led by the U.S. Geological Survey, two traits were identified that indicate how chemicals can build up and reach toxic levels:  how easily a chemical is broken down or metabolized by an organism and the chemical’s ability to dissolve in water.

    These traits account for how most chemicals concentrate, or biomagnify, in ever-higher levels as one goes up the food chain from its base to its top predators, such as fish, people, or polar bears. Chemicals that have the ability to biomagnify, such as DDT, can have adverse effects on human and wildlife health and the environment. 

     

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  • Ocean currents push phytoplankton and pollution faster than thought

    The billions of single-celled marine organisms known as phytoplankton can drift from one region of the world's oceans to almost any other place on the globe in less than a decade, Princeton University researchers have found.

    Unfortunately, the same principle can apply to plastic debris, radioactive particles and virtually any other man-made flotsam and jetsam that litter our seas, the researchers found. Pollution can thus become a problem far from where it originated within just a few years.

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  • MIT finds tectonic collisions had major impact on climatic shifts

    For hundreds of millions of years, Earth's climate has remained on a fairly even keel, with some dramatic exceptions: Around 80 million years ago, the planet's temperature plummeted, along with carbon dioxide levels in the atmosphere. The Earth eventually recovered, only to swing back into the present-day ice age 50 million years ago. 

    Now geologists at MIT have identified the likely cause of both ice ages, as well as a natural mechanism for carbon sequestration. Just prior to both periods, massive tectonic collisions took place near the Earth's equator -- a tropical zone where rocks undergo heavy weathering due to frequent rain and other environmental conditions. This weathering involves chemical reactions that absorb a large amount of carbon dioxide from the atmosphere. The dramatic drawdown of carbon dioxide cooled the atmosphere, the new study suggests, and set the planet up for two ice ages, 80 million and 50 million years ago. 

     

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  • Which trees face death in drought?

    Two hundred-twenty-five million trees dead in the southwest in a 2002 drought. Three hundred million trees in Texas in 2011. Twelve million this past year in California.  Throughout the world, large numbers of trees are dying in extreme heat and drought events. Because mass die-offs can have critical consequences for the future of forests and the future of Earth’s climate, scientists are trying to understand how a warming climate could affect how often tree mortality events occur – and how severe they could become.

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  • Shift in global winds caused record flooding in the Balkans

    Disastrous floods in the Balkans two years ago are likely linked to the temporary slowdown of giant airstreams, scientists found. These wind patterns, circling the globe in the form of huge waves between the Equator and the North Pole, normally move eastwards, but practically stopped for several days then -- at the same time, a weather system got stuck over Bosnia and Herzegovina, Serbia and Croatia that poured out record amounts of rain. The study adds evidence that so-called planetary wave resonance is a key mechanism for causing extreme weather events in summer. Further, the scientists showed that extreme rainfall events are strongly increasing in the Balkans, even more than the globally observed rise.

    "We were surprised to see how long the weather system that led to the flooding stayed over the region -- it's like the Vb cyclone 'Yvette' was trapped there," says Lisa Stadtherr from the Potsdam Institute for Climate Impact Research (PIK), lead-author of the study to be published in Science Advances. "Day after day the rain was soaking the soil until it was saturated, which lead to the flooding that reportedly caused several dozen casualties and 3.5 billion Euro of damages."

     

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  • Clear cutting and its influence on carbon storage

    lear-cutting loosens up carbon stored in forest soils, increasing the chances it will return to the atmosphere as carbon dioxide and contribute to climate change, a Dartmouth College study shows.

    The findings appear in the journal Soil Science.

    Soil is the world's largest terrestrial carbon pool. In northern hardwood forests in the United States, mineral soil pools store up to 50 percent of total ecosystem carbon. Logging and other land-use changes are a major cause of soil carbon release, but there has been recent interest to further understand soil carbon dynamics in forested ecosystems after logging. This is of particular importance in the northeastern U.S. because of the great potential for the use of biomass as part of a diversified renewable energy portfolio.

    The Dartmouth researchers explored whether clear-cutting changes the strength of the chemical bonds of carbon stored in mineral soils in hardwood forests in the northeastern United States. Clear-cutting involves harvesting all timber from a site at once rather than selectively culling mature trees. Carbon is stored in soil by binding only to certain soil structures.

    The researchers collected soils from recently clear-cut forests and from older forests, and pulled carbon from the soil in a sequence of gentle to stronger extractions. The results showed that mature forest stands stored significantly more soil organic carbon in strongly mineral-bound and stable carbon pools than did soils from cut stands.

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