Wednesday, November 24, 2010

Busy microbial world discovered in deepest ocean crust ever explored

Map of the Altantis Massif showing the locations of the Integrated Ocean Drilling Program Expeditions 304 and 305, Hole 1309D (yellow circle) and the Lost City Hydrothermal Field (green circle). From Mason et al. 2010

From Oregon University

The first study to ever explore biological activity in the deepest layer of ocean crust has found bacteria with a remarkable range of capabilities, including eating hydrocarbons and natural gas, and “fixing” or storing carbon.

The research, just published in the journal
PLoS One, showed that a significant number and amount of bacterial forms were present, even in temperatures near the boiling point of water.

“This is a new ecosystem that almost no one has ever explored,” said
Martin Fisk, a professor in the College of Oceanic and Atmospheric Sciences (COAS) at Oregon State University. “We expected some bacterial forms, but the long list of biological functions that are taking place so deep beneath the Earth is surprising.”

Oceanic crust covers about 70 percent of the surface of the Earth and its geology has been explored to some extent, but practically nothing is known about its biology – partly because it’s difficult and expensive, and partly because most researchers had assumed not all that much was going on.

The temperature of the sediments and rock increases with depth, and scientists now believe that the upper temperature at which life can exist is around 250 degrees.
The ocean floor is generally composed of three levels, including a shallow layer of sediment; basalt formed from solidified magma; and an even deeper level of basalt that cooled more slowly and is called the “gabbro” layer, which forms the majority of ocean crust.

The gabbro layer doesn’t even begin until the crust is about two miles thick.
But at a site in the Atlantic Ocean near an undersea mountain, the Atlantis Massif, core samples were obtained from gabbro rock formations that were closer to the surface than usual because they had been uplifted and exposed by faulting.
This allowed the researchers to investigate for the first time the microbiology of these rocks.

A research expedition drilled more than 4,600 feet into this formation, into rock that was very deep and very old, and found a wide range of biological activity.
Microbes were degrading hydrocarbons, some appeared to be capable of oxidizing methane, and there were genes active in the process of fixing, or converting from a gas, both nitrogen and carbon.

The findings are of interest, in part, because little is known about the role the deep ocean crust may play in carbon storage and fixation.
Increasing levels of carbon dioxide, a greenhouse gas when in the atmosphere, in turn raise the levels of carbon dioxide in the oceans.

But it now appears that microbes in the deep ocean crust have at least a genetic potential for carbon storage, the report said.
And it may lend credence to one concept for reducing carbon emissions in the atmosphere, by pumping carbon dioxide into deep subsurface layers where it might be sequestered permanently.

The researchers also noted that methane found on Mars could be derived from geological sources, and concluded that subsurface environments on Mars where methane is produced could support bacteria like those found in this study.

“These findings don’t offer any easy or simple solutions to some of the environmental issues that are of interest to us on Earth, such as greenhouse warming or oil spill pollution,” Fisk said. “However, they do indicate there’s a whole world of biological activity deep beneath the ocean that we don’t know much about, and we need to study.”

Microbial processes in this expansive subseafloor environment “have the potential to significantly influence the biogeochemistry of the ocean and the atmosphere,” the researchers wrote in their report.

The research was supported by the National Science Foundation, U.S. Department of Energy, Gordon and Betty Moore Foundation, and the Integrated Ocean Drilling Program. Collaborators were from OSU, the Lawrence Berkeley National Laboratory, Tohoku University in Japan, Universitat Bremen in Germany, University of Oklahoma, and National Institute of Advanced Industrial Science and Technology in Japan.

Links :

Tuesday, November 23, 2010

More than a million Atlantic sharks killed yearly

From AFP

At least 1.3 million sharks, many listed as endangered, were harvested from the Atlantic in 2008 by industrial-scale fisheries unhampered by catch or size limits, according to a tally released Monday
The actual figure may be several fold higher due to under-reporting, said the
study, released by advocacy group Oceana on the sidelines of a meeting of the International Commission for the Conservation of Atlantic Tunas (ICCAT)
Convening in Paris through November 27, the 48-member ICCAT is charged with ensuring that commercial fisheries are sustainable. It has the authority to set catch quotas and restrictions.

While the global spotlight has been trained on the plight of Atlantic bluefin tuna, many species of high-value sharks are in even more dire straits, say marine biologists.
"Sharks are virtually unmanaged at the international level," said Elizabeth Griffin Wilson of Oceana. "ICCAT has a responsibility to protect our oceans' top predators."

Under the UN Convention on the Law of the Sea, "highly migratory" sharks must be managed by international bodies.

Of the 21 species found in the Atlantic, three-quarters are classified as threatened with extinction.
North Atlantic populations of the oceanic white tip, for example, have declined by 70 percent, and hammerheads by more than 99 percent, according to the International Union for the Conservation of Nature (IUCN).

Other species -- including the porbeagle, common thresher and shortfin mako -- have also been overexploited, and may be teetering on the brink of viability.

Many are fished for their fins -- prized as a delicacy in Chinese cuisine -- and then tossed, dead or dying, back into the sea once the choice morsels have been sliced off.

The practice is prohibited, but loopholes in the regulation have allowed the ban to be widely ignored.
Oceana and several conservation groups, backed by some governments, have called upon ICCAT to set catch quotas and other protective measures for these and other vulnerable sharks.

The United States has proposed requiring that all sharks be brought back to shore whole, which would boost enforcement of the finning ban and help scientists measure population levels.

Japan -- which quashed a drive earlier this year to protect four threatened shark species under the UN Convention on International Trade in Endangered Species (CITES) -- is now urging ICCAT to prohibit fishing one of them, the oceanic white tip.

The initiative "is an example showing our commitment for conservation of shark resources," the head of the Japanese delegation said in an opening statement.

Sharks have reigned at the top of the ocean food chain for hundreds of millions of years.
But the consummate predators are especially vulnerable to industrial-scale overfishing because they mature slowly and produce few offspring.

"The classic fisheries management approach of 'fishing down' a given population to its so-called maximum sustainable yield, and then assuming it can recover, does not work for sharks," said Matt Rand, a shark expert at the Washington-based Pew Environment Group.
Tens of millions of the open-water hunters are extracted from global seas every year.

Regional studies have shown that when shark populations crash the impact cascades down through the food chain, often in unpredictable and deleterious ways.

Links :
  • WashingtonPost : Migratory sharks face intense fishing pressure
  • WorldFishing : Shark campaigners, ICCAT action needed
  • HuffingtonPost : Pew Environment Group, shark attack survicors fight for shark conservation
  • GeoGarage blog : Shark-finning puts species on verge of extinction

Monday, November 22, 2010

Bottom of the water

''One touch of nature makes the world Kin'' W. Shakespeare

Héen Tàak is a documentary exploring the wilderness of Alaska’s Inner Passage.
A discovery of the edge of glaciers at the bottom of the ocean among men and women who fully live their philosophy of love and respect in an intimate privileged relationship with water.
The wilderness offers unique and surprising wonders, above and under water, revealing a host of fascinating species.

Héen Tàak, ("Bottom of the water" in
Tlingit langage.) the new film by the awards winning director Nathalie Lasselin (2010 Best of Alaska award. Alaska international film festival)

Sunday, November 21, 2010

Hurricane forecasts can be made years in advance



From Wired

The parade of storms that pummels the western fringe of the North Atlantic every year just got a bit more predictable.
Scientists say they have developed a way to forecast how many Atlantic hurricanes there will be — not just for the upcoming year, as some groups already do each spring, but for several years out.

“This is the first time anyone has reported skill in predicting the number of hurricanes beyond the seasonal time scale,” says Doug Smith, a climate modeler at the Met Office Hadley Centre in Exeter, England.
A paper by Smith and his colleagues appeared online Nov. 7 in
Nature Geoscience.

Knowing how hurricane trends could change in the future, he says, will help society prepare for the damage of the kind that Hurricane Tomas recently dealt the Caribbean.

Atlantic hurricane activity waxes and wanes over a cycle of several decades, and since 1995 has been in an active part of that cycle.
Researchers have been working to tease apart the causes of this cycle and to predict how future changes, like rising sea-surface temperatures, might affect storms.

Smith’s team uses one of the hottest areas of climate modeling: decadal climate prediction, which aims to understand both how the climate system varies internally, along with external factors like greenhouse gases and volcanic eruptions.

The researchers used nine versions of its decadal prediction model to “hindcast” Atlantic hurricanes each year from 1960 to 2007.
The model was set to May 1 for each of those years and then was asked how many storms would come that season.
Averaging across the nine versions, the model results closely matched the changing number of hurricanes that occurred over those decades. Smith says: “We’ve found that there is some skill there.”

Next the team tackled long-term predictions, by starting on Nov. 1 of each year between 1960 and 2005 and forecasting the number of hurricanes for 10 years out.
Again, Smith says, the model tracked the observations well, particularly within the first couple of years.

But the study can’t yet show exactly what makes hurricanes more frequent.
Climate researchers disagree over whether past increases in hurricane activity were due to internal variability, external factors like greenhouses gases, or both.

By watching how well the model matches reality while changing these factors, Smith’s team suggests that at least some of the recent increase in Atlantic hurricane frequency comes from external factors.
The next step, Smith says, is to run more comparisons and see which of those might be most important.

Many researchers think that global warming will indeed affect how many storms form.
If atmospheric carbon dioxide levels double over preindustrial levels by the year 2100 as many expect, “we should expect an increase in the frequency of the strongest hurricanes in the Atlantic, roughly by a factor of two by the end of the century,” says a group led by modeler Morris Bender of NOAA’s Geophysical Fluid Dynamics Laboratory in Princeton, New Jersey. Their analysis appeared in
Science in January.

Within the next few months, Smith’s team plans to forecast how many Atlantic hurricanes there will be over the next few years.

So far this season the Atlantic has had 20 named storms, 12 of them hurricanes.
That’s in line with NOAA’s May forecast, which called for 14 to 23 named storms, of which 8 to 14 would be hurricanes.

The Atlantic hurricane season ends Nov. 30.

Links :
  • Marine GeoGarage blog

Saturday, November 20, 2010

How Cousteau inspired my love of the oceans



From BBC

Jacques Cousteau co-invented the aqua-lung, which brought diving to the masses, he pioneered underwater camera techniques, and he was the godfather of the modern conservation movement. But 100 years since his birth, Cousteau remains somewhat of an enigma.

Growing up, I remember Saturday mornings vividly. As soon as we heard that distinctive epic theme music trill out, my brother and I knew there was three seconds to don our red caps (pulled down at a jaunty French angle) and jump in front of the TV for the next instalment of Cousteau's underwater adventures.

Who didn't want to be a member of Jacques Cousteau's Calypso crew? The Calypso, as it set sail into the next conservation adventure, was the most exciting place to be on the planet.

So in his anniversary year, I set out to find the man behind the French accent. What drove him to his impossible challenges and, when he died in 1997, who took on the Cousteau cap?

As ocean conservation becomes one of the biggest challenges of our time, what can we learn from Cousteau to take forward in communicating the intrinsic value of the oceans today - and to help a whole new generation fall in love with the sea?

As Cousteau said: "People protect what they love. A lot of people attack the sea, I make love to it."

But Cousteau was not always a conservationist.

He was born in an era when blowing things up (including habitats and other species) for the sake of science and exploration were far more the norm.

Yet as the world became more and more connected with modern technologies and with the birth of TV, he soon began to realise the devastating effects of human impact on our planet.

Turning this new media to his advantage, Cousteau realised the red cap could be his iconic symbol and TV his powerful international communication tool.

Soon, Cousteau became the most important spokesperson for the world's health.

Motivating generations to protect the oceans, from Sylvia Earle, the famous diver, to Wes Anderson the director of the film The Life Aquatic with Steve Zissou (a film inspired by Cousteau), his work has touched many people.

But his legacy is more complicated.

'Exhilarating'

Whilst his family, including his sons Jean-Michel and Philippe and his grandchildren (Fabien and Céline, Philippe Jr and Alexandra), have all devoted their lives to the ocean, the mantel of the Calypso or red cap seems more illusive.

The crew members of the Calypso have carried on with Cousteau's work and I was eager to meet them and get a sense of what life was like onboard the great ship.

So on a sunny September day, I found myself standing at the Harbour Key in Marseille with Albert Falco, former captain of the Calypso, and Denis Martin-Laval, former ship's doctor.

These were men well into their 80s whose lives on the ocean had left them far younger in every way than many half their age. (Readers take note.)

To meet them was an exhilarating experience, especially when I was invited to go back to Denis' house for lunch and to take a tour of his handmade model of the Calypso. Denis talked me through his experience on the ship, as he peeled back layer after layer of the exact replica.

You could see not only how important this boat had been to the conservation movement, but also how it has been a giant chapter in these men's lives - Albert Falco was captain for 40 years.

A feeling of excitement and camaraderie of long days at sea and a sense of purpose also overwhelmed me. I could almost smell the salt air.

Back at the quay side in Marseille, I thought about the anticipation there must have been as the Calypso prepared to set sail on its next high seas adventure.

It was these people coming together to do great things, seemingly impossible things, that created a conservation legacy worth remembering. It was certainly this magic that we need to hold onto to encourage new conservationists into the world.

As Cousteau said: "The sea, the great unifier, is man's only hope. Now, as never before, the old phrase has a literal meaning: we are all in the same boat."

Links :