Earth ChangesS


Floods kill 25 in Mozambique

Maputo - Torrential rains have killed 25 people in central Mozambique in the last two weeks and flooding could devastate the region by March, authorities said on Monday.

The victims, mostly children, drowned while trying to swim through raging waters, said Belarmino Chivambo, spokesman of Mozambique's National Institute of Disaster Management.

"We expect the worst to come by March, which is the peak of the rainy season due to heavy downpours in both Mozambique and neighboring countries," he told Reuters.

Thousands of homes have been destroyed and authorities are setting up emergency shelters, said Chivambo. Roads, bridges and electricity pylons in four provinces have been damaged.

The Zambezi River in central Mozambique, which stretches 500 km (300 miles) through four provinces, is now above flood alert levels, swelled by rains in neighboring Malawi and Zambia.

Bizarro Earth

Dirty Snow Causes Early Runoff In Cascades, Rockies

soot from pollution settles on pristine snow
© Pacific Northwest National LaboratoryWhen soot from pollution settles on pristine snow, it can increase snowmelt in the winter month of February (top left, red) and decrease it in the late spring (May -- bottom right, blue).

Soot from pollution causes winter snowpacks to warm, shrink and warm some more. This continuous cycle sends snowmelt streaming down mountains as much as a month early, a new study finds. How pollution affects a mountain range's natural water reservoirs is important for water resource managers in the western United States and Canada who plan for hydroelectricity generation, fisheries and farming.

Scientists at the Department of Energy's Pacific Northwest National Laboratory conducted the first-ever study of soot on snow in the western states at a scale that predicted impacts along mountain ranges. They found that soot warms up the snow and the air above it by up to 1.2 degrees Fahrenheit, causing snow to melt.

"If we can project the future -- how much water we'll be getting from the rivers and when -- then we can better plan for its many uses," said atmospheric scientist Yun Qian. "Snowmelt can be up to 75 percent of the water supply, in some regions. These changes can affect the water supply, as well as aggravate winter flooding and summer droughts."

Better Earth

Decline Of Plankton That Gobble Carbon Dioxide Coincided With Ancient Global Cooling

© NOAA/Gordon TaylorDiatoms are abundant oceanic plankton that remove billions of tons of carbon dioxide from the air each year. Their evolutionary history needs to be rewritten, according to a new Cornell study.

The evolutionary history of diatoms -- abundant oceanic plankton that remove billions of tons of carbon dioxide from the air each year -- needs to be rewritten, according to a new Cornell study. The findings suggest that after a sudden rise in species numbers, diatoms abruptly declined about 33 million years ago -- trends that coincided with severe global cooling.

The study is published in the Jan. 8 issue of the journal Nature.

The research casts doubt on the long-held theory that diatoms' success was tied to an influx of nutrients into the oceans from the rise of grasslands about 18 million years ago. New evidence from a study led by graduate student Dan Rabosky of Cornell's Department of Ecology and Evolutionary Biology and the Cornell Laboratory of Ornithology takes into account a widespread problem in paleontology: that younger fossils are easier to find than older ones.

"We just tried to address the simple fact that the number of available fossils is colossally greater from recent time periods than from earlier time periods," Rabosky said. "It's a pretty standard correction in some fields, but it hasn't been applied to planktonic paleontology up till now."

Bizarro Earth

Large Earthquakes Trigger A Surge In Volcanic Eruptions

New evidence showing that very large earthquakes can trigger an increase in activity at nearby volcanoes has been uncovered by Oxford University scientists.

An analysis of records in southern Chile has shown that up to four times as many volcanic eruptions occur during the year following very large earthquakes than in other years. This 'volcanic surge' can affect volcanoes up to at least 500 km away from an earthquake's epicentre.

A report of the work will be published in the journal Earth and Planetary Science Letters.

Previously, scientists had identified a few cases where volcanic eruptions follow very large earthquakes - but up until now it had been difficult to show statistically that such earthquakes may be the cause of an increase in eruptions, rather than the events just being a coincidence.


Hind Wings Help Butterflies Make Swift Turns To Evade Predators, Study Finds

© Image courtesy of Cornell University CommunicationsButterflies in flight.
New tires allow race cars to take tight turns at high speeds. Hind wings give moths and butterflies similar advantages: They are not necessary for basic flight but help these creatures take tight turns to evade predators.

"To escape a predator, you don't have to be fast, you just have to be more erratic," said Tom Eisner, a world authority on animal behavior, ecology and evolution and the Jacob Gould Schurman Professor Emeritus of Chemical Ecology at Cornell. Eisner is co-author of a study on butterfly wings recently published in the Proceedings of the National Academy of Sciences (105: 43).


Nature Hits Back: Major spike in shark attacks on Australian beaches

Shark Attacks 1
© FlickerThe victim described the shark as a bull shark
An aerial search will resume on the New South Wales south coast tomorrow for a shark that attacked a 24-year-old man.

Steven Fogarty was snorkelling at Windang near the entrance to Lake Illawarra when the shark bit him on the leg, leaving 40 puncture wounds.

He described the shark as a bull shark and said he punched the shark until it let go.


Medicinal plants on verge of extinction

The health of millions could be at risk because medicinal plants used to make traditional remedies, including drugs to combat cancer and malaria, are being overexploited. "The loss of medicinal plant diversity is a quiet disaster," says Sara Oldfield, secretary general of the NGO Botanic Gardens Conservation International.

Most people worldwide, including 80 per cent of all Africans, rely on herbal medicines obtained mostly from wild plants. But some 15,000 of 50,000 medicinal species are under threat of extinction, according to a report this week from international conservation group Plantlife. Shortages have been reported in China, India, Kenya, Nepal, Tanzania and Uganda.

Commercial over-harvesting does the most harm, though pollution, competition from invasive species and habitat destruction all contribute. "Commercial collectors generally harvest medicinal plants with little care for sustainability," the Plantlife report says. "This can be partly through ignorance, but [happens] mainly because such collection is unorganised and competitive."

Cloud Lightning

Emergency declared in Fiji as six feared dead in severe storm, floods

A state of emergency was declared in Fiji Sunday as severe storms brought widespread flooding with at least six people feared dead.

Thousands were evacuated from their homes and those living in low-lying areas were advised to move to higher ground as rivers burst their banks.

Tourists in the popular resort area of Denarau Island were trapped after the only road to the airport was inundated.

Interim Prime Minister Voreqe Bainimarama declared the state of emergency on the recommendation of the National Disaster Management Office (Dismac), Interim National Security Minister Epeli Ganilau said.


Dozens dead in Romanian cold snap

Forty-three people have died in Romania since late December due to the extremely cold temperatures, the deputy secretary-of-state for health, Raed Arafat, announced Saturday.

The dead included a three-month old baby, Arafat was quoted as saying by Newsin news agency.

Romania has experienced a major cold snap, with temperatures dropping as low as minus 31 degrees Celsius (minus 23.8 degrees Fahrenheit) in the centre of the country.

Cloud Lightning

Storm sinks Indonesian ferry, 250 feared dead

Jakarta, Indonesia -- A ferry capsized in a severe storm and crashing waves in central Indonesia on Sunday and officials said around 250 people were feared dead.

Eighteen survivors were rescued by fishing boats, but the fate of the others remained unclear, said Taufik, a port official at Parepare on the island of Sulawesi, where the ferry began its journey. Taufik uses one name, as is common in Indonesia.

About 250 passengers and 17 crew are believed to have been onboard the ferry when it went down 30 miles (50 kilometers) off the coast off western Sulawesi. Indonesians generally don't know how to swim and it was feared that most onboard would have drowned.