Archive for 11/25/2011

Daily Astorian –

The tsunami two years ago in American Samoa has given scientists a chance to examine an issue that often seems of little significance in the immediate aftermath of these massive disasters; the little-seen, rarely studied but often frightening damage done to offshore coral reefs.

A new study by scientists from Oregon and Michigan, done with a remotely operated undersea vehicle (ROV) surveyed large areas of that area’s coral reefs, and revealed significant damage from sediment, debris, and the enormous forces of both the incoming and outgoing waves.

Corals are delicate living organisms that can only survive in shallow, nearshore areas where they get adequate sunlight.

That’s also where the tsunami wave action is most violent, and they are especially vulnerable to its impacts; but often ignored in the understandable concern about terrestrial damage and loss of life.

“Very little until now has been known about the impact of tsunamis on coral reefs,” said Solomon Yim, a professor of structural and ocean engineering at Oregon State University and co-author of the study, which was supported by the National Science Foundation.

“These are huge forces and often these events have happened in remote locations of the world where we had little opportunity to study them,” Yim said. “American Samoa gave us the chance to use some very sophisticated equipment to gain a much better understanding of what damage is being done to coral reefs, and what might be done in the future to help reduce it.”

On Sept. 29, 2009, a magnitude 8.3 subduction zone earthquake near American Samoa sent waves crashing into many islands, destroying buildings and eroding coastlines with waves up to 20 feet high that came almost a mile inland and killed more than 180 people.

It was the world’s largest earthquake that year. The onshore devastation was heavy. Although not seen at the time, so was the underwater damage to coral reefs.

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Bryan nelson – 

It’s the sponge that takes the idea of a sponge bath to a whole new level: the giant Neptune’s Cup.

First discovered in 1822, these sponges once grew so large that they were commonly used as bath tubs for children. However, that handy use quickly led to overharvesting, and the last time anyone saw one alive was in 1908.

Many believed the sponges had become extinct. That was until March of this year, when biologists doing a routine survey dive along Singapore’s coast spotted something that none of them could immediately identify.

Of course they couldn’t: a living Neptune’s Cup sponge hadn’t been spied for more than 100 years.But there it was — two of them, in fact, just 50 meters from one another.

Sponge expert Lim Swee Cheng, author of the book “A Guide to Sponges of Singapore,” was called in to confirm the finding, according to a report by Scientific American.

“My heart skipped a beat when I saw it in Singapore waters this year,” Lim recently wrote on his Facebook page, after positively identifying the sponges as Neptune’s Cups.

With diameters measuring 30 centimeters across, the pair of newly discovered sponges are tiny compared to legend, which described heights of more than a meter and diameters wide enough to hold a bathing human.

These new discoveries are just babies, say scientists — but they are growing fast. And their presence may indicate that a more stable population exists nearby.

“The presence of two young Neptune’s Cup sponges within a surveyed area of 50m by 50m signals hope that more are present within the area,” said marine biologist Karenne Tun, one of the scientists to rediscover the species.

“More importantly, [it] points to the possibility of adult populations present within Singapore’s coastal waters.”

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Charles Choi –

The world’s earliest known fish hooks reveal that humans fished the open sea for much longer than previously thought.

Past studies have revealed that early humans were capable of crossing the open ocean as far back as 50,000 years ago, such as they did to colonize Australia.

Until now, however, evidence that such mariners could fish while in the open sea dated back only to 12,000 years ago.

“In most areas of the world, evidence for our early ancestors’ coastal exploitation is now submerged — it was drowned by rising sea levels,” researcher Sue O’Connor, an archaeologist at Australian National University in Canberra, told LiveScience.

Now O’Connor and her colleagues have found evidence of prehistoric fishing gear and the remains of large fish such as tuna at a cave shelter known as Jerimalai, located in the Southeast Asian island nation of East Timor.

“East Timor became a new independent nation in 1999 when they voted for independence from Indonesian rule,” O’Connor noted.

“Most of the country’s infrastructure was destroyed when the Indonesians withdrew and tens of thousands of people were killed during the fight for independence.”

“However, the country is rebuilding, and it never ceases to amaze me that people who have experienced so much hardship and who are so poor can be so generous,” she added.

“I think working with the local East Timorese people who always assist my field team has been one of the most uplifting experiences of my life.”

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Hydro International – 

On the eve of the centenary of Sir Robert Falcon Scott’s expedition to the Antarctic, the British Antarctic Survey (BAS) 20011/12 field season is underway.

The start of the season is marked by the arrival of dozens of scientists and support staff, together with tonnes of equipment and fresh supplies, at BAS’s five Antarctic research stations.

More than twenty ‘deep field’ science teams will live under canvas for weeks or months at a time to collect samples or conduct experiments that will give new insight into the Antarctic environment and try to answer big questions about global issues like climate change.

One remote and inaccessible field camp is Pine Island Glacier. Around 1,400km from BAS’s Rothera Research Station on the Antarctic Peninsula, two scientists and their support mountaineers will use radar and seismic techniques to find out how the most rapidly thinning glacier on the West Antarctic Ice Sheet (WAIS) is contributing to global sea level rise.

In the same area of WAIS, preparations are underway for a large ground-based traverse in 2012/13. Giant tractors and a custom built caboose complete with kitchen, shower and sleeping quarters will travel 450kms across challenging Antarctic terrain as part of the iSTAR Programme (the Ice Sheet Stability Research Programme).

Over 90 tonnes of equipment are heading to this remote and hostile location to prepare for next year.

The four-week traverse, which also involves a ship-borne component to take measurements and deploy moorings at the ice edge, will look more closely at how Pine Island and Thwaites Glaciers are thinning, the processes involved and how they are contributing to global sea level rise.

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