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.

Sandhill cranes vs windmills

The current placement of wind energy towers in the central and southern Great Plains may have relatively few negative effects on sandhill cranes wintering in the region, according to a U.S. Geological Survey study published today.

Midcontinental sandhill cranes are important to sporting and tourism industries in the Great Plains, an area where wind energy development recently surged. Scientists with the USGS compared crane location data from the winters of 1998-2007 with current wind tower sites in Texas, Oklahoma, Kansas and New Mexico prairies. Findings showed only a seven percent overlap between cranes and towers, and that most towers have been placed in areas not often used by cranes during the winter.

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. 

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.

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. 

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.

Educating Consumers About Buying Sustainably

Sustainability is a word tossed around much these days. But do consumers really care about buying sustainably? The answer is yes. More and more consumers are interested in sustainability, as surveys show.  A 2011 consumer survey by Nielsen found that 66 percent of socially-conscious consumers cited environmental sustainability as the most important issue from a list of 18 issues.

So, how do you increase awareness of buying sustainably among consumers? The key is getting information to them. A study by Michigan State University researchers, published in 2014 in the Business and Economics Journal, looked at consumer awareness of fair trade information. The researchers found that informed consumers “are better positioned to make sound decisions and take the appropriate actions to address sustainability issues.” Providing access to “complete and accurate sources of information allows consumers to draw the connection between their consumption behaviors and social, and environmental sustainability,” the researchers concluded.

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."

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.

Study shows most US roofs can support a solar system

Most U.S. rooftops in good repair can take the weight of solar photovoltaic (PV) systems. That’s the conclusion of a three-year study by a research team led by Sandia National Laboratories.

“There is a misperception in the building industry that existing residential rooftops lack the strength to carry the weight load of rooftop solar photovoltaic installations,” said Sandia structural engineer Steve Dwyer. “Most existing well-built wooden rooftops can support PV system loads.”

Sandia took on the job of analyzing rooftop structural strength to address concerns raised in the U.S. Department of Energy’s (DOE) Solar America Cities program. The agency named 25 cities to promote adoption of solar technology at a comprehensive, local level through photovoltaics.