When dams are built they have an impact not only on the flow of water in the river, but also on the people who live downstream and on the surrounding ecosystems. By placing data from close to 6,500 existing large dams on a highly precise map of the world’s rivers, an international team led by McGill University researchers has created a new method to estimate the global impacts of dams on river flow and fragmentation.
Scientists analyzing data from NASA’s Kepler satellite have boosted the tally of known or suspected planets beyond our solar system to more than 4000, they reported here today at a meeting of the American Astronomical Society. Most are inhospitable—too big, too hot, or too cold for any conceivable life form. But another team seeking to verify Kepler candidates announced here today that they had identified eight new potentially habitable planets, including some close to Earth in size and situation. “We’ve significantly increased the list of verified small planets in the habitable zone,” says Douglas Caldwell of the SETI Institute in Mountain View, California.
Lake Erie just can’t catch a break. The lake has experienced harmful algal blooms and severe oxygen-depleted “dead zones” for years, but now a team of researchers led by Carnegie’s Anna Michalak and Yuntao Zhou has shown that the widespread drought in 2012 was associated with the largest dead zone since at least the mid-1980s.
Until now, the size of the dead zone each summer and the factors explaining the variability from year to year have been elusive. Using 28 years of data collected in and around the lake, the team was able to “measure” the size of the dead zone each summer and identify factors that explain the year-to-year variability for the first time. They found that the 2012 drought, with extremely low water inflow from tributaries, was associated with a record-breaking dead zone in the lake, and that meteorological factors together with agricultural practices explain why these events vary annually. Previous studies have focused on phosphorous from agricultural runoff as the primary driver of the lake’s dead zones, but this analysis shows that the inflow of water from tributaries is actually the largest explanatory factor. The results are published in Environmental Science & Technology.
A new study suggests pharmaceuticals and chemicals from personal care products end up in swimming pools, possibly interacting with chlorine to produce disinfection byproducts with unknown properties and health effects. Chlorination is used primarily to prevent pathogenic microorganisms from growing. Previous research has shown that many constituents of urine including urea, uric acid, and amino acids, interact with chlorine to produce potentially hazardous disinfection byproducts in swimming pools. However, chemicals from pharmaceuticals and personal care products, or PPCPs, also could be interacting with chlorine, producing potentially harmful byproducts.
Getting in shape is one of the most common New Year's resolutions. And whether or not we follow through with going to the gym or watching what we eat, a new study by King's College London and the University of Birmingham reveals that staying active allows us to age optimally-another push to help us keep with our New Year's resolution.
Responsible for 400,000 deaths each year globally, air pollution has yet to be sufficiently addressed by the world's governments, researchers have warned. Air pollution damages the heart. According to an expert position paper published in the European Heart Journal, many types of cardiovascular disease are linked to poor air quality.
Not only does air pollution exacerbate existing heart problems, but it also appears to play a role in the development of heart disease in otherwise healthy people, the researchers said. There is particularly strong evidence of the harmful effects of suspended particles, as opposed to gas pollution, they said.
Gushing downpours finally arrived in California last month, when December rains brought some relief to a landscape parched after three years of severe drought. But the rain came too late for thousands of Chinook salmon that spawned this summer and fall in the northern Central Valley. The Sacramento River, running lower than usual under the scorching sun, warmed into the low 60s — a temperature range that can be lethal to fertilized
Chinook, the largest species of Pacific salmon, need cool waters to reproduce.
The Institution of Chemical Engineers (IChemE) is urging coordinated action to reduce the amount of hidden water used in food and drink production – estimated at up to 1.8 million litres per person every year equivalent to an Olympic size swimming pool. Each person consumes between 2,000-5,000 litres of water embedded in their food, every day – or between 730,000-1,825,000 million litres annually. Currently, around 90 per cent of all freshwater is used by agriculture (70 per cent) and industry (20 per cent), leaving just 10 per cent for domestic use.
Aviation emissions are a major clause of climate change, writes Valerie Brown - yet they remain unregulated. The gap between the best and worst performing airlines demonstrates ample opportunities for improvement - but is the political will there to impose effective regulation?
The performance gap suggests the industry could reduce GHG emissions significantly if the least efficient airlines would emulate the most efficient.
If commercial aviation were a country, it would rank seventh in global greenhouse gas emissions according to a recent report by the International Council on Clean Transportation(ICCT).
Ever wonder what's in the black cloud that emits from some semi trucks that you pass on the freeway? Lawrence Berkeley National Laboratory (Berkeley Lab) scientist Thomas Kirchstetter knows very precisely what's in there, having conducted detailed measurements of thousands of heavy-duty trucks over months at a time at two San Francisco Bay Area locations.
â€‹With a specially outfitted research van equipped with sophisticated monitors for several pollutant types, he and his team are studying emissions levels from diesel trucks to understand and analyze the impact of new control technologies and California air pollution regulations.
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