Earth ChangesS


Collapse of the Ice Bridge Supporting Wilkins Ice Shelf Appears Imminent

Wilkins ice bridge rift
© ESANew rifts detected on ice bridge
The Wilkins Ice Shelf is at risk of partly breaking away from the Antarctic Peninsula as the ice bridge that connects it to Charcot and Latady Islands looks set to collapse. The beginning of what appears to be the demise of the ice bridge began this week when new rifts forming along its centre axis resulted in a large block of ice breaking away.

The Advanced Synthetic Aperture Radar (ASAR) images acquired on 2 April by ESA's Envisat satellite confirm that the rifts are quickly expanding along the ice bridge. Dr Angelika Humbert from the Institute of Geophysics, Münster University, and Dr Matthias Braun from the Center for Remote Sensing, University of Bonn, witnessed the recent development during their daily monitoring activities of the ice sheet using data from Envisat and the German Aerospace Center's TerraSAR-X satellite.

graphic of antarctica & wilson ice shelf
© NASA image by Robert Simmon, based on data from Joey ComisoBetween 1981 and 2007, most of Antarctica warmed. Portions of West Antarctica experienced an especially rapid rise in temperature.
Interesting there's no mention of the very possible and natural explanation for West Antarctica's warming - a volcano., In 2008, scientists from the British Antarctic Survey reported a layer of volcanic ash and glass shards frozen within an ice sheet in western Antarctica. The volcano punched a hole right through due to its heat and force.

For a more indepth analysis of the anomalous warming/cooling of Antarctica, see here


Bizarro Earth

5.6 Earthquake Jolts Central Japan

An earthquake with a preliminary magnitude of 5.6 jolted Kyushu in southern Japan on Sunday, the Japan Meteorological Agency said.

The focus of the quake, which occurred at 6:36 p.m., was some 30 km underground in the Hyuganada region of Kyushu. There were no reports of injuries or damage.

No tsunami warning was issued.

The quake registered 4 on the Japanese seismic intensity scale of 7 in the city of Miyazaki and 3 in neighboring areas, according to the agency.

Bizarro Earth

Evacuation ordered as Chile volcano erupts again

Llaima volcano
© UnknownLlaima volcano
Chile's Llaima volcano, one of the most active in South America, spewed out a river of lava more than 1,100 yards long on Saturday in a fresh eruption, prompting officials to order dozens of people to evacuate.

Llaima, which lies in Chile's picturesque lake region about 435 miles south of the capital Santiago, erupted on January 1, 2008, and has belched rock and ash sporadically since then.

The lava and hot gases from the latest eruption are melting snow on the sides of the volcano, and authorities say some towns are in danger of being hit by mudslides.

Bizarro Earth

US: 3 earthquakes shake East Tennessee in 8 days

The U.S. Geological Survey says East Tennessee was struck by three small earthquakes in eight days.

A magnitude 1.0 quake hit near Madisonville on March 25. A magnitude 1.3 quake hit six miles north of Cleveland in Bradley County on March 29.

WVLT-TV reports a 1.0 magnitude quake hit Thursday at 11:02 a.m., about 12 miles southeast of Tellico Plains in the Cherokee National Forest. The epicenter originated 7.6 miles underground from a ridge near Brookshire Creek.


Sexy or repulsive? Butterfly wings can be both to mates and predators

© William PielOliver found that the eyespots of some butterflies, such as this pair of mating Bicyclus anynana, serve to both
Butterflies seem able to both attract mates and ward off predators using different sides of their wings, according to new research by Yale University biologists.

Trying to find the balance between these two crucial behaviors is one of nature's oldest dilemmas, according to Jeffrey Oliver, a postdoctoral associate in Yale's Department of Ecology and Evolutionary Biology and lead author on the study, which appears online today in the journal Proceedings of the Royal Society B: Biological Sciences.

"You want to be noticeable and desirable for mates, but other onlookers, including predators, are paying attention to those signals as well."

Oliver was interested in whether the eyespots on the upperside of butterflies' wings - specifically, those of bush brown butterflies - serve a different purpose than the ones on the underside. Ever since Darwin's time, biologists (including Darwin himself) have postulated whether the upperside patterns could be used to attract mates, while at the same time, those on the underside could help avoid predators.


Scripps Scientists Help Decode Mysterious Green Glow of the Sea

green bioluminesence
© unknownExperiments by Dimitri Deheyn and Michael Latz revealed green bioluminescence.
Dual purpose discovered for worm's brilliant bioluminescent light

Many longtime sailors have been mesmerized by the dazzling displays of green light often seen below the ocean surface in tropical seas. Now researchers at Scripps Institution of Oceanography at UC San Diego have uncovered key clues about the bioluminescent worms that produce the green glow and the biological mechanisms behind their light production.

Marine fireworms use bioluminescence to attract suitors in an undersea mating ritual. Research conducted by Scripps marine biologists Dimitri Deheyn and Michael Latz reveals that the worms also may use the light as a defensive measure. The report, published as the cover story of the current issue of the journal Invertebrate Biology, provides insights into the function of fireworm bioluminescence and moves scientists closer to identifying the molecular basis of the light.

"This is another step toward understanding the biology of the bioluminescence in fireworms, and it also brings us closer to isolating the protein that produces the light," said Deheyn, a scientist in the Marine Biology Research Division at Scripps. "If we understand how it is possible to keep light so stable for such a long time, it would provide opportunities to use that protein or reaction in biomedical, bioengineering and other fields-the same way other proteins have been used."

Better Earth

Alaska's Mount Redoubt has another large eruption

The Mount Redoubt volcano had another large eruption Saturday after being relatively quiet for nearly a week.

Radar indicated a plume of volcanic ash rose 50,000 feet into the sky, making it one of the largest eruptions since the volcano became active on March 22, said the National Weather Service.

The ash cloud was drifting toward the southeast and there were reports of the fine, gritty ash falling in towns on the Kenai Peninsula.


Birds Can 'Read' Human Gaze

© iStockphoto/Dmitry MaslovWe all know that people sometimes change their behavior when someone is looking their way. Jackdaws --- birds related to crows and ravens with eyes that appear similar to human eyes --- can do the same.
"Jackdaws seem to recognize the eye's role in visual perception, or at the very least they are extremely sensitive to the way that human eyes are oriented," said Auguste von Bayern, formerly of the University of Cambridge and now at the University of Oxford.

When presented with a preferred food, hand-raised jackdaws took significantly longer to retrieve the reward when a person was directing his eyes towards the food than when he was looking away, according to the research team led by Nathan Emery of the University of Cambridge and Queen Mary University of London. The birds hesitated only when the person in question was unfamiliar and thus potentially threatening.

In addition, the birds were able to interpret human communicative gestures, such as gaze alternation and pointing, to help them find hidden food, they found. The birds were unsuccessful in using static cues, including eye gaze or head orientation, in that context.

Bizarro Earth

Urban hunters do most harm to ape populations

© WSPA/K. Ammann/Rex Features Ape parts discovered in markets tell little of how the populations are faring.
Commercial hunters from towns are exacting a much bigger toll on great apes than subsistence hunters from small villages, according to an analysis of ape nest density near human settlements.

The finding that numbers of gorillas and chimpanzees appear to have dwindled twice as much near towns in Gabon than near villages supports a focus on conservation efforts that tackle commercial hunting over those that aim to convince villagers to give up subsistence hunting, says Hjalmar Kühl at the Max-Planck-Institute for Evolutionary Anthropology in Leipzig, Germany, who conducted the study with colleagues.

The team counted sleeping nests left by gorillas and chimps in Gabon's mountainous Moukalaba Doudou National Park. They found that nest density decreased the closer they got to the towns that surround the park. The towns' populations range from 10,000 to 18,000 people.

Although some nests could be found close to the towns, their overall density was only half that seen in the centre of the park. In contrast, the team found no such gradient near smaller villages.


UK: Public asked to take part in largest ever survey of garden amphibians and reptiles

© GettyFrogs spend time in garden ponds when hibernating or breeding
Frogs, newts and other "pond life" found at the bottom of the garden are to be counted in the first UK survey of reptiles and amphibians.

Hundreds of frogs, toads, snakes and lizards can live at the bottom of town and country gardens.

However global warming and development means many species are increasingly at risk. Of the 13 species of amphibians and reptiles native to the UK, 10 are considered endangered including the great crested newt, natterjack toad, adder and pool frog. Other species like grass snakes or common frogs are also suffering from habitat loss.

The national "stock take" of newts, toads, snakes and other traditional "garden pests" has been organised by a network of conservation groups including the British Trust for Ornithology and Froglife.