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As global temperatures rise, how will lake ecosystems respond? As they warm, will lakes -- which make up only 3 percent of the landscape, but bury more carbon than the world's oceans combined -- release more of the greenhouse gases carbon dioxide and methane? And might that create a feedback loop that leads to further warming?

To predict the effects of rising air temperatures on the carbon cycle of lakes, Rensselaer Polytechnic Institute researchers will link computer models of changing weather, water temperature, and emissions of carbon dioxide and methane for 2,000 lakes across the United States, including Lake George, through 2105. The project is supported with a $300,000 grant from the National Science Foundation, and led by Kevin Rose, an assistant professor in the Department of Biological Sciences at Rensselaer and the Frederic R. Kolleck '52 Career Development Chair in Freshwater Ecology.

Oceanographers from MIT and Woods Hole Oceanographic Institution report that the northeast Pacific Ocean has absorbed an increasing amount of anthropogenic carbon dioxide over the last decade, at a rate that mirrors the increase of carbon dioxide emissions pumped into the atmosphere.

The scientists, led by graduate student Sophie Chu, in MIT's Department of Earth, Atmospheric, and Planetary Sciences, found that most of the anthropogenic carbon (carbon arising from human activity) in the northeast Pacific has lingered in the upper layers, changing the chemistry of the ocean as a result. In the past 10 years, the region's average pH has dropped by 0.002 pH units per year, leading to more acidic waters. The increased uptake in carbon dioxide has also decreased the availability of aragonite -- an essential mineral for many marine species' shells.

Earth requires fuel to drive plate tectonics, volcanoes and its magnetic field. Like a hybrid car, Earth taps two sources of energy to run its engine: primordial energy from assembling the planet and nuclear energy from the heat produced during natural radioactive decay. Scientists have developed numerous models to predict how much fuel remains inside Earth to drive its engines -- and estimates vary widely -- but the true amount remains unknown.

Tropical island nations should team up to ban coral-killing sunscreen products, following the example of Hawaii, a conference has heard. Chemical compounds in sunscreen lotions cause irreparable damage to reefs, which are crucial to the livelihoods of 500 million people in the tropics, scientist and policymakers said at the IUCN World Conservation Congress on 3 September. Hawaii is leading a legistlative effort to ban the use of sunscreen that contains oxybenzone or similar harmful agents at its beaches.

A new study from Lancaster University has discovered toxic nanoparticles from air pollution in large quantities in human brains. The researchers examined brain tissue from 37 people aged between 3 and 92 years old in the U.K. and Mexico. Magnetite, a type of iron oxide, was found in massive quantities in the samples – millions of particles per gram of brain tissue.