Photo by study author Pascal Geraghty, New South Wales Department of Primary Industry

By WhySharksMatters from Southern Fried Science

Last week, a team of 10 Australian scientists announced that they had found the world’s first “shark hybrids”, offspring of individuals from two different shark species which had interbred. During a routine survey of Australian marine life, 57 sharks were found that physically resembled one species of shark, but had genetic markers inconsistent with that species. Subsequent genetic investigation revealed that these 57 animals were hybrids between common blacktip sharks (Carcharhinus limbatus) and Australian blacktip sharks (C. tilstoni).

Some of these hybrids were “F1?, meaning that one parents was a common blacktip and one was an Australian blacktip. Others were “B+”(backcrossed), which means that one parent was a common blacktip/Australian blacktip hybrid, and the other was a “purebreed” of one of those two species. According to the study’s lead author, Dr. Jess Morgan of the University of Queensland, ”our genetic marker tells us that these hybrids are ‘at least’ F1, and that these animals are reproductively viable and can produce an F2…the hybrids may be generations past F2 but the existing genetic markers can’t distinguish how many generations past the second cross have occurred.”

To Read More…

By Elisabeth Rosenthal from The New York Times

Clamshell containers on supermarket shelves in the United States may depict verdant fields, tangles of vines and ruby red tomatoes. But at this time of year, the tomatoes, peppers and basil certified as organic by the Agriculture Department often hail from the Mexican desert, and are nurtured with intensive irrigation.

Growers here on the Baja Peninsula, the epicenter of Mexico’s thriving new organic export sector, describe their toil amid the cactuses as “planting the beach.”

Del Cabo Cooperative, a supplier here for Trader Joe’s and Fairway, is sending more than seven and a half tons of tomatoes and basil every day to the United States by truck and plane to sate the American demand for organic produce year-round.

To Read More…

Katey M. Walter Anthony, a scientist, investigated a plume of methane, a greenhouse gas, at an Alaskan lake. Dr. Walter Anthony is a leading researcher in studying the escape of methane. Photo by Josh Haner from The New York Times

By Justin Gillis from The New York Times

A bubble rose through a hole in the surface of a frozen lake. It popped, followed by another, and another, as if a pot were somehow boiling in the icy depths.

Every bursting bubble sent up a puff of methane, a powerful greenhouse gas generated beneath the lake from the decay of plant debris. These plants last saw the light of day 30,000 years ago and have been locked in a deep freeze — until now.

“That’s a hot spot,” declared Katey M. Walter Anthony, a leading scientist in studying the escape of methane. A few minutes later, she leaned perilously over the edge of the ice, plunging a bottle into the water to grab a gas sample.

To Read More…

A coal-fired power plant in Changchun, China. Many environmental officials say all countries should be bound by the same rules. Photo from the Associated Press

By John M. Broder from The New York Times

For 17 years, officials from nearly 200 countries have gathered under the auspices of the United Nations to try to deal with one of the most vexing questions of our era — how to slow the heating of the planet.

Every year they leave a trail of disillusion and discontent, particularly among the poorest nations and those most vulnerable to rising seas and spreading deserts. Every year they fail to significantly advance their own stated goal of keeping the average global temperature from rising more than 2 degrees Celsius, or about 3.6 degrees Fahrenheit, above preindustrial levels.

That was the case again this year. The event, the 17th conference of the United Nations Framework Convention on Climate Change, wrapped up early Sunday morning with modest accomplishments: the promise to work toward a new global treaty in coming years and the establishment of a new climate fund.

To Read More…

Photo by The EPA

From The Economist 

“I’M SORRY,” said the UN bureaucrat, a flush of emotion flickering across his perspiring face. “I’m sorry, but this is something that bothers me a lot.” He paused to compose himself.

The problem was the Saudi Arabians, who the previous night had threatened to block the passage of a parcel of agreements at the ongoing UN climate change summit in Durban. They were demanding an addition to it—a commitment to look into ways to compensate oil producers for the losses they would suffer if the world stopped burning fossil fuels. If this did not happen, the oil sheikhs would withhold their support from the entire package, of finance, forestry, technology and other climate-friendly measures.

Most of the scores of diplomats present were appalled. Not least those from small island nations, like Kiribati and Tuvalu, which are likely to disappear beneath the rising seas long before the Saudis have drained their last well. But it mattered naught. Agreements can only be reached at the UN climate summit—properly known as the 17th Conference of the Parties to the UN Framework Convention on Climate Change (or COP 17)—through a consensus of the 200-odd countries represented at it. After a fraught few hours of bickering, the Saudis got their wretched commitment.

To Read More…

Image by Brett Ryder

From the Economist

Shorlty before the 2009 UN climate summit in Copenhagen, many companies got into green. The summit was expected to lead to new regulations restricting greenhouse-gas emissions. Dozens of chief executives came to see history being made and to be seen on the right side of it. But Copenhagen was a flop. Most firms turned their thoughts elsewhere. Only four bosses showed up at the next annual climate meet, in Cancún. Few are expected at this year’s bash, which begins in Durban on November 28th.

Alas, that represents a realistic assessment of the Durban summit’s chances of delivering anything like the long-term certainty that businesses crave. Of 300 bosses of big global firms recently quizzed by Ernst & Young, 83% said they wanted to see a legally binding multilateral deal struck in Durban to update the ailing Kyoto protocol and help to put a price on carbon emissions. But only 18% expect this to happen. The absence of a clear climate policy helps explain why, for example, investment in British clean technology fell from around $11 billion in 2009 to $3 billion last year. It would also suggest that any firm factoring a steep carbon price into its plans—as Shell does, assuming a notional price of $40 a tonne—should quietly lower it.

To Read More…

Image by Gerhard Kuhn, Alfred Wegener Institute

From ScienceDaily

The end of the last ice age and the processes that led to the melting of the northern and southern ice sheets supply basic information on changes in our climate. Although the maximum size of the ice sheet in the northern hemisphere during the last ice age is relatively well known, there is little reliable data on the dimensions of the Antarctic ice sheet. A publication appearing in the journal Science on 1 December now furnishes indications that the two hemispheres attained their maximum ice sheet size at nearly the same time and started melting 19,000 years ago.

The decline in the Antarctic ice sheets thus commenced almost 5,000 years earlier than assumed to date, though our investigations show great regional differences and demonstrate how important deepwater archives are,” says the lead author of the study, Dr. Michael Weber from the Geological Institute of the University of Cologne.

To Read More…

Image by Jefferson Beck/Goddard Space Flight Center/NASA/AP

By Charles Q. Choi from the Christian Science Monitor

Antarctica’s vast ice sheets first grew when carbon dioxide levels in the Earth’s atmosphere sharply declined millions of years ago, scientists now find.

Carbon dioxide is a greenhouse gas — it traps heat radiating away from the Earth’s surface. High levels of it in the atmosphere are linked with global warming, while low levels are linked with global cooling. Many such periods of warming and cooling have occurred in the Earth’s history, with repercussions for climate around the planet.

But reconstructions of what atmospheric carbon dioxide levels were like back when glaciers began to cover Antarctica nearly 34 million years ago had appeared contradictory. Some research actually suggested carbon dioxide levels rose just before and across this time, a period known as the Eocene-Oligocene climate transition, which is the opposite of what would be expected as prime glacier-growing conditions.

To Read More…

From Nasa.gov

Get a real tree this holiday season. Buy it or cut it yourself at a tree farm. Either way, you will be helping the environment.

Surprised? Most people think it’s bad to cut a live holiday tree. Instead, they buy an artificial tree made of plastic or other synthetic material. Because they reuse this artificial tree year after year, they think they are saving real trees.

But not so. Farmers grow trees especially for the holidays. They plant huge tracts of land in beautiful noble pines, Douglas firs, blue spruce, and other favorites. It may take 8 to 12 years to grow a good sized tree. But during that time, the tree is taking in carbon dioxide and releasing oxygen. It is cleaning the air and helping global warming. If people didn’t buy the cut trees, the farmers wouldn’t plant them.

To Read More…

From the Washington Post

The global output of heat-trapping carbon dioxide jumped by the biggest amount on record, the U.S. Department of Energy calculated, a sign of how feeble the world’s efforts are at slowing man-made global warming.

The new figures for 2010 mean that levels of greenhouse gases are higher than the worst case scenario outlined by climate experts just four years ago.

“The more we talk about the need to control emissions, the more they are growing,” said John Reilly, co-director of MIT’s Joint Program on the Science and Policy of Global Change.

To Read More…