Taxonomy term

timothy oleson

Virtual water: Tracking the unseen water in goods and resources

Trading in “virtual water” — rainfall and irrigation water used in the production of food commodities or other goods and services, but that isn’t part of the final product — between water-rich and water-poor regions has been suggested as a means to allay water scarcity. And recently, the virtual water concept has gained a foothold among a number of governments and multinational businesses, potentially shaping approaches to water sustainability in the future.

21 Sep 2014

Red Planet Roundup: September 2014

As Curiosity and Opportunity rove around Mars, the Mars Reconnaissance Orbiter (MRO), Mars Express and Mars Odyssey orbit above, and scientists on Earth study the Red Planet from afar, new findings are announced almost weekly. Here are a few of the latest updates.

12 Sep 2014

New climate record challenges ideas about recent glaciations

Predicting how a changing climate and rising sea levels might impact humans in the future requires an understanding of how Earth has changed in the past. So scientists are continually seeking more and better data to help illuminate earlier conditions.
 

08 Sep 2014

Nutrient runoff feeding Baltic Sea dead zone

Low-oxygen, or hypoxic, deep waters now extend over an area of about 60,000 square kilometers in the Baltic Sea, a tenfold increase compared to 115 years ago, according to a recent study published in Proceedings of the National Academy of Sciences. The hypoxic zone has fluctuated substantially in that period, but much of the expansion has occurred in recent decades as a result of large inputs of nutrients like nitrogen and phosphorus from human activities such as agriculture, reported Jacob Carstensen of Aarhus University in Denmark and colleagues.
 

03 Sep 2014

Sunken logs a delicacy for ocean bottom-feeders

Wood isn’t often on the menu for deep sea-dwelling critters, but for some species, there’s nothing like a tasty tree stump for dinner. Five years after leaving bundles of Acacia wood 3,200 meters deep at the bottom of Monterey Canyon off the central California coast, biologists retrieved the bundles with a remotely operated vehicle and found that some hosted diverse colonies of organisms.
 

29 Aug 2014

Volcanic ash feed southern ocean plankton

Ash plumes from volcanoes in South America and elsewhere may spur large blooms of plankton in otherwise barren parts of the Southern Ocean, but maybe not for the reason scientists have suspected, according to a new study. Such blooms are of interest because they consume atmospheric carbon dioxide, although their overall effect on climate remains far from clear.
 

28 Aug 2014

The subcontinent's sturdy mammals

India is home to some hardy mammals, according to a new study in Proceedings of the National Academy of Sciences. Researchers reported that 20 of 21 mammalian taxa identified from fossils found in southern India have survived on the subcontinent over at least the last 100,000 years, with some lineages stretching back twice that long.
 

27 Aug 2014

Extra rib may be sign of mammoth decline

High rates of a congenital defect in woolly mammoths may offer evidence that inbreeding and environmental stress contributed to the animals’ demise during the Late Pleistocene, according to a new analysis of fossil mammoth neck bones.

26 Aug 2014

South American fossils offer revised view of Gondwana assembly

Fossils of a known age have been found for the first time in rocks in Brazil that, although long-studied, had previously eluded scientists’ attempts to pinpoint their age. The discovery of the marine animals dates the rocks to 550 million years ago, researchers say, offering important insights into the geological evolution and timing of the assembly of the former supercontinent Gondwana.
 

25 Aug 2014

Warm river water melted Arctic sea ice

In September 2012, the area of the Arctic Ocean covered by sea ice was the smallest on record since satellite monitoring began in 1979. Several factors are thought to have contributed to that summer’s diminished ice, including a large cyclone in August that brought warmer ocean waters into the area and broke up the ice and a longer-term trend of thinning and weakening sea ice. Now, researchers have found that at least one large burst of warm freshwater into the Arctic earlier in the summer probably played a role as well.
 

23 Aug 2014

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