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A new analysis suggests that large-scale wave energy systems developed in the Pacific Northwest should be comparatively steady, dependable and able to be integrated into the overall energy grid at lower costs than some other forms of alternative energy, including wind power.

The findings, published in the journal Renewable Energy, confirm what scientists have expected – that wave energy will have fewer problems with variability than some energy sources and that by balancing wave energy production over a larger geographic area, the variability can be even further reduced.

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.

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.

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. 

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.