A new study suggests that increases in atmospheric CO2 could intensify extreme droughts in tropical and subtropical regions -- such as Australia, the southwest and central United States, and southern Amazonia -- at much a faster rate than previously anticipated, explains University of Texas at Austin professor Rong Fu in a commentary in the March 9 edition of Proceedings of the National Academy of Sciences.

Sea ice increases in Antarctica do not make up for the accelerated Arctic sea ice loss of the last three decades, according to the stark findings of a new NASA study. As a whole, the planet has been shedding sea ice at an average annual rate of 13,500 square miles (35,000 square kilometers) since 1979, the equivalent of losing an area of sea ice larger than the state of Maryland every year. Sea ice increases in Antarctica do not make up for the accelerated Arctic sea ice loss of the last three decades, according to the stark findings of a new NASA study.

This post originally was published on WRI.org.

How does bioenergy contribute to a sustainable food and climate future?

A new WRI paper finds bioenergy can play a modest role using wastes and other niche fuelstocks, but recommends against dedicating land to produce bioenergy. The lesson: do not grow food or grass crops for ethanol or diesel or cut down trees for electricity.

Even modest quantities of bioenergy would greatly increase the global competition for land. People already use roughly three-quarters of the world’s vegetated land for crops, livestock grazing and wood harvests. The remaining land protects clean water, supports biodiversity and stores carbon in trees, shrubs and soils -- a benefit increasingly important for tackling climate change. The competition for land is growing, even without more bioenergy, to meet likely demands for at least 70 percent more food, forage and wood.

A team of researchers led by Kathryn McKain of Harvard University has recently discovered that approximately three percent of the natural gas delivered to Boston leaks directly into the atmosphere, taking with it a heavy load of methane, a known greenhouse gas. Their study doesn’t just have significant environmental implications: It’s estimated that the city is losing around $90 million to leaks every year. Correcting leaks is a relatively straightforward task, though it would require some investment in natural gas infrastructure and consumer education. However, these costs would be mitigated by the substantial savings offered if Boston was able to cut down on its methane problem.

Changes in drinking water quality in the 21st Century are coming from a myriad of circumstances, and not all are for the best. Top contenders for why water-drinking quality might become suspect to the average consumer include California's drought conditions, the technology of fracking, and the nationwide aging infrastructure of rusty, degrading pipes.

Citing these and other relatively recent scenarios, Andrea Dietrich, professor of civil and environmental engineering at Virginia Tech, and her colleague Gary A. Burlingame of the Philadelphia Water Department, are calling for a critical review and rethinking of the U.S. Environmental Protection Agency's (EPA) secondary standards for maintaining consumers' confidence in tap water as well as in its sensory quality.

The greatest concentrations of the world's soil carbon have been pinpointed by researchers - and much of it is a dangerously flammable addition to climate change concerns. An international scientific survey of peat bogs has calculated that they contain more carbon than all the world's forests, heaths and grasslands together - and perhaps as much as the planet's atmosphere. Since peat can smoulder underground for years, it is another potential factor in global warming calculations.

The “warming hiatus” that has occurred over the last 15 years has been caused in part by small volcanic eruptions. Scientists have long known that volcanoes cool the atmosphere because of the sulfur dioxide that is expelled during eruptions. Droplets of sulfuric acid that form when the gas combines with oxygen in the upper atmosphere can persist for many months, reflecting sunlight away from Earth and lowering temperatures at the surface and in the lower atmosphere. Previous research suggested that early 21st-century eruptions might explain up to a third of the recent warming hiatus.

Despite record heat and drought Australia's emissions and coal exports are soaring, says a new report, and both are increasing as a matter of government policy. But a homegrown climate action movement is putting a spanner in the works - and just stopped its first coal train.

Australia's response to climate change is headed completely backwards. If we can stop this new coal mine we set a precedent for the rest of Australia to stand up.

There are consequences of the successful efforts worldwide to save beavers from extinction. Along with the strong increase in their population over the past 100 years, these furry aquatic rodents have built many more ponds, establishing vital aquatic habitat. In doing so, however, they have created conditions for climate changing methane gas to be generated in this shallow standing water, and the gas is subsequently released into the atmosphere. In fact, 200 times more of this greenhouse gas is released from beaver ponds today than was the case around the year 1900, estimates Colin J. Whitfield of the University of Saskatchewan in Canada. He led a study in Springer's journal AMBIO² about the effect that the growth in beaver numbers in Eurasia and the Americas could be having on methane emissions.

The fur trade of the sixteenth to nineteenth centuries nearly led to the extinction of beaver populations worldwide. After trapping was limited and conservation efforts led to the re-introduction of these animals into their natural ranges, the number of North American (Castor canadensis) and Eurasian (Castor fiber) beavers grew. The North American beaver has also been introduced to Eurasia and South America (specifically the archipelago of Tierra del Fuego); establishment of these populations has, in effect, created an anthropogenic greenhouse gas source in these landscapes.

Average chloride concentrations often exceed toxic levels in many northern United States streams due to the use of salt to deice winter pavement, and the frequency of these occurrences nearly doubled in two decades. Chloride levels increased substantially in 84 percent of urban streams analyzed, according to a U.S. Geological Survey study that began as early as 1960 at some sites and ended as late as 2011. Levels were highest during the winter, but increased during all seasons over time at the northern sites, including near Milwaukee, Wisconsin; Chicago, Illinois; Denver, Colorado; and other metropolitan areas. The report was published today in the journal Science of the Total Environment.