ScienceDaily: Top Environment News

Shark tooth weapons reveal missing shark species in Central Pacific islands

Posted: 03 Apr 2013 05:02 PM PDT

The Gilbert Island reefs in the Central Pacific were once home to two species of sharks not previously reported in historic records or contemporary studies. The species were discovered in a new analysis of weapons made from shark teeth and used by 19th century islanders.

Satellite tagging maps the secret migration of white sharks

Posted: 03 Apr 2013 05:01 PM PDT

Long-life batteries and satellite tagging have been used to fill in the blanks of female white sharks’ (Carcharodon carcharias) lifestyles. New research defines a two year migratory pattern in the Pacific Ocean. Pregnant females travel between the mating area at Guadalupe Island and nursery in Baja California, putting them and their young at risk from commercial fishing.

2013 wintertime Arctic sea ice maximum fifth lowest on record

Posted: 03 Apr 2013 11:14 AM PDT

During the cold and dark of Arctic winter, sea ice refreezes and achieves its maximum extent, usually in late Feb. or early Mar. According to a NASA analysis, this year the annual maximum extent was reached on Feb. 28 and it was the fifth lowest sea ice winter extent in the past 35 years.

Chimps: Ability to ‘think about thinking’ not limited to humans

Posted: 03 Apr 2013 11:14 AM PDT

Humans’ closest animal relatives, chimpanzees, have the ability to “think about thinking” — what is called “metacognition,” according to new research.

‘A better path’ toward projecting, planning for rising seas on a warmer Earth

Posted: 03 Apr 2013 11:14 AM PDT

More useful projections of sea level are possible despite substantial uncertainty about the future behavior of massive ice sheets. In two recent articles, researchers present an approach that provides a consistent means to integrate the potential contribution of continental ice sheets such as Greenland and Antarctica into sea-level rise projections.

Rocky mountains originated from previously unknown oceanic plate

Posted: 03 Apr 2013 11:14 AM PDT

The mountain ranges of the North American Cordillera are made up of dozens of distinct crustal blocks. A new study clarifies their mode of origin and identifies a previously unknown oceanic plate that contributed to their assembly. Geologists were able to locate the remnants of several deep-sea trenches that mark subduction sites at which oceanic plates plunge at a steep angle into the mantle and are drawn almost vertically into its depths.

Environmental policies matter for growing megacities

Posted: 03 Apr 2013 10:13 AM PDT

A new study shows clean-air regulations have dramatically reduced acid rain in the United States, Europe, Japan and South Korea over the past 30 years, but the opposite is true in fast-growing East Asian megacities, possibly due to lax antipollution rules or lack of enforcement.

Ancient pool of warm water questions current climate models

Posted: 03 Apr 2013 10:13 AM PDT

A huge pool of warm water that stretched out from Indonesia over to Africa and South America four million years ago suggests climate models might be too conservative in forecasting tropical changes. Present in the Pliocene era, this giant mass of water would have dramatically altered rainfall in the tropics, possibly even removing the monsoon. Its decay and the consequential drying of East Africa may have been a factor in Hominid evolution. The missing data for this phenomenon could have significant implications when predicting the future climate.

Thin clouds drove Greenland’s record-breaking 2012 ice melt

Posted: 03 Apr 2013 10:13 AM PDT

If the sheet of ice covering Greenland were to melt in its entirety tomorrow, global sea levels would rise by 24 feet. Three million cubic kilometers of ice won’t wash into the ocean overnight, but researchers have been tracking increasing melt rates since at least 1979. Last summer, however, the melt was so large that similar events show up in ice core records only once every 150 years or so over the last four millennia.

Invasive crabs help Cape Cod marshes

Posted: 03 Apr 2013 09:20 AM PDT

Ecologists are wary of non-native species, but along the shores of Cape Cod where grass-eating crabs have been running amok and destroying the marsh, an invasion of predatory green crabs has helped turn back the tide in favor of the grass.

New system to study trigger of cell death in nervous system developed

Posted: 03 Apr 2013 09:19 AM PDT

Researchers have developed a new model system to study a receptor protein that controls cell death in both humans and fruit flies.

Earth is ‘lazy’ when forming faults like those near San Andreas

Posted: 03 Apr 2013 07:42 AM PDT

Some geoscientists have taken an uncommon, “Earth is lazy” approach to modeling fault development in the crust and it is providing new insights into how faults grow. In particular, this group is studying irregularities along strike-slip faults, the active zones where plates slip past each other such as at the San Andreas Fault of southern California.

Chinese foreign fisheries catch 12 times more than reported, study shows

Posted: 03 Apr 2013 07:42 AM PDT

Chinese fishing boats catch about US$11.5 billion worth of fish from beyond their country’s own waters each year — and most of it goes unreported, according to a new study.

Breakthrough in hydrogen fuel production could revolutionize alternative energy market

Posted: 03 Apr 2013 07:41 AM PDT

Researchers have discovered a way to extract large quantities of hydrogen from any plant, a breakthrough that has the potential to bring a low-cost, environmentally friendly fuel source to the world.

Tiny octopus-like microorganisms named after science fiction monsters

Posted: 03 Apr 2013 06:27 AM PDT

Researchers have discovered two new symbionts living in the gut of termites, and taken the unusual step of naming them after fictional monsters created by American horror author HP Lovecraft. The single-cell protists, Cthulhu macrofasciculumque and Cthylla microfasciculumque, help termites digest wood.

Breeding birds vulnerable to climate change in arctic alaska: A story of winners and losers

Posted: 03 Apr 2013 06:25 AM PDT

A new report looked at the vulnerability of 54 breeding bird species to climate change impacts occurring by the year 2050 in Arctic Alaska. The assessment found that two species, the gyrfalcon and common eider are likely to be “highly” vulnerable, while seven other species would be “moderately” vulnerable to anticipated impacts. Five species are likely to increase in number and benefit from a warming climate.

Physicists decipher social cohesion issues

Posted: 03 Apr 2013 04:20 AM PDT

Migrations happen for a reason, not randomly. A new study, based on computer simulation, attempts to explain the effect of so-called directional migration – migration for a reason – on cooperative behaviors and social cohesion. The authors devised a computer simulation of what they refer to as selfish individuals – those who are mainly concerned with their own interests, to the exclusion of the interests of others. In this study, they propose a new migration rule, dubbed directional migration, in existing models referred to as evolutionary game theory.