Feature Article

Broad-scale studies of climate change effects on freshwater species have focused mainly on temperature, ignoring critical drivers such as flow regime and biotic interactions. We use downscaled outputs from general circulation models coupled with a hydrologic model to forecast the effects of altered flows and increased temperatures on four interacting species of trout across the interior western United States (1.01 million km2), based on empirical statistical models built from fish surveys at 9,890 sites.

The combined effects of climate change, energy scarcity, and water paucity require that we radically rethink our agricultural systems. Countries can and must reorient their agricultural systems toward modes of production that are not only highly productive, but also highly sustainable. Following the 2008 global food price crisis, many developing countries have adopted new food security policies and have made significant investments in their agricultural systems. Global hunger is also back on top of the international agenda.

Dust has the potential to modify global climate by influencing the radiative balance of the atmosphere and by supplying iron and other essential limiting micronutrients to the ocean. Indeed, dust supply to the Southern Ocean increases during ice ages, and ‘iron fertilization’ of the subantarctic zone may have contributed up to 40 parts per million by volume (p.p.m.v.) of the decrease (80–100 p.p.m.v.) in atmospheric carbon dioxide observed during late Pleistocene glacial cycles.

Images of the sea floor in Pine Island Bay, West Antarctica, reveal impressive evidence that a massive ice-shelf break-up occurred before about 12,000 years ago, and point to a tidal influence on sea-floor features produced during deglaciation.

Discharges from pharmaceutical factories contaminate rivers on three continents.

A tough-minded law has boosted Brazil's environmental record in recent years by helping to drive the rate of destruction in the Amazon rainforest to historic lows. But a backlash in the hinterlands is threatening to weaken the country's forest code and push deforestation rates back up again.

Generating energy from crops instead of oil and coal can have counterproductive effects. “The use of biomass can lead to additional emissions of greenhouse gases”, says lead author Alexander Popp of the Potsdam Institute for Climate Impact Research (PIK). “This is the case if forests get cut down to plant energy crops instead.” Forests are important CO2 sinks. At the same time, biomass is expected to play an important role in  future energy systems.

http://iopscience.iop.org/1748-9326/6/3/034017/fulltext