The Reserve Bank of Zimbabwe had capped maximum daily withdrawals at 500,000 Zimbabwean dollars — about 25 U.S. cents, and about a quarter of the price of a loaf of bread. But faced with mounting chaos in a country already in economic free fall, the bank decided last week to raise that limit to 100 million dollars ($50 U.S.) per week.

Soldiers were deployed to all banks in anticipation of throngs of people lining up to withdraw money Thursday, when the increase took effect. Wednesday, police chased depositors away and arrested union leaders who planned to protest the limits.

Zimbabwe’s inflation rate of 231 million percent is the world’s highest. In addition, the country is faced with a growing outbreak of cholera that its government declared a national emergency Thursday.

The outbreak has killed at least 565 people and sickened more than 11,000, the U.N. Humanitarian Affairs Office said. Medical professionals blame the resurgence of the water-borne disease on the lack of safe water in many parts of the country.

The Zimbabwe Congress of Trade Unions said 69 people were arrested across the country during Wednesday’s demonstrations. Amnesty International has demanded to know the whereabouts of human rights activist Jestina Mukoko, whom it said was abducted at dawn Wednesday by armed men in plainclothes posing as police.

And angry, unpaid soldiers clashed with foreign currency exchangers and some civilians Monday, three days after troops who had failed to get cash from their banks looted shops they suspected to be illegally dealing in foreign currency.

Harare also appealed for help for its hospitals, which Health Minister David Parirenyatwa said "are literally not functioning."

"Our staff is demotivated and we need your support to ensure that they start coming to work and our health system is revived," he said at a meeting of donors including United Nations agencies, embassies and non-governmental institutions, The Herald reported.

Cholera cases are on the increase in nine of Zimbabwe’s 10 provinces, the U.N. Office for the Coordination of Humanitarian Affairs (OCHA) warned Wednesday. It blamed "poor water and sanitation supply, a collapsed health system and limited government capacity to respond to the emergency."

OCHA said the water-borne outbreak had killed at least 565 people and sickened more than 11,000.

“Most dramas include this kind of thing [and] there’s a great deal of poetic licence in what they do,” said linguistics and phonetics expert Paul Faulkes of the University of York.

Faulkes, who has provided training in forensic speech analysis for the U.S. Secret Service and the FBI, spoke at a meeting of the ARC Network in Human Communication Science in Sydney.

Forensic speech science, which involves acoustic, phonetic and linguistic analysis of recordings, can be used to try and narrow down possible suspects. It can also be used to determine how well a suspect’s voice matches a criminal’s voice.

But, said Faulkes, a recording of speech can never be used to identify someone with certainty on its own.

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“There is no such thing as a voice print,” he said. “It’s a very very dangerous term. There is no single feature of a voice that is indelible that works like a fingerprint does.”

Many different factors influence how people speak at any particular time and place.

“If you’re tired or if you have a cold or if you’re speaking on a phone against traffic in the background you do all sorts of things to the voice, which make it phonetically very different from time to time,” said Faulkes, who also works as a freelance consultant for a private forensic speech science laboratory.

“The features of speech and language are such that you can’t use them as a marker of identity to identify one person and exclude all other people under normal circumstances. People’s voices overlap.”

In addition, said Faulkes, acoustic analysis using software must contend with the problems associated with the recording. For example, voices are often analyzed from wire taps, covert recordings taken from someone’s pocket or messages from a voicemail.

While speech analysis cannot be used to identify someone on its own, it can be used to eliminate suspects, said Faulkes.

The Center for Biological Diversity sued the U.S. Fish and Wildlife Service and Interior Secretary Dirk Kempthorne on Wednesday for failing to act on a petition seeking protection for walruses under the Endangered Species Act.

Walruses are threatened by global warming that melts Arctic sea ice, according to the group, one of the parties that successfully petitioned to list polar bears as threatened. The group also has filed petitions to protect Arctic seals.

The walrus petition was filed in February. The Fish and Wildlife Service was required by law to decide by May 8 whether the petition had merit, which would trigger a more thorough review and a preliminary decision after 12 months. The agency missed the deadline.

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Rebecca Noblin, an attorney for the Center for Biological Diversity, said the delay would harm walruses.

“Every day that goes by without protecting the walrus, we’re emitting more greenhouse gases, accelerating the ice melt,” Noblin said.

“In addition to the climate change, the other main threat is oil and gas development that continues to go forward without any consultation regarding walrus,” she said.

Fish and Wildlife spokesman Bruce Woods said Wednesday the agency anticipates making a decision on the petition soon but has limited resources. Decisions on endangered species listings are driven by litigation, he said, forcing the agency to rank actions by court order rather than species need.

Two experts, Kurt Zenz House, cofounder of the Harvard Energy Journal Club, and Julie Shoemaker, a doctoral candidate at Harvard University, argue below that the best solution is to bury CO2 underground. A third, Peter Montague of Environmental Research Foundation, counters on page two with a completely different opinion.

Kurt Zenz House and Julie Shoemaker:

Carbon-based fuels are the basis of modern civilization. Oil accounts for about 90 percent of transportation and coal comprises about 50 percent of electricity production. But burning fossil fuels produces CO2, which is altering Earth’s atmosphere and affecting the planet in dangerous ways. In order to minimize the risks, we need to decrease CO2 emissions dramatically over the coming decades.

Many people, including seasoned political leaders, investors, academics, journalists and entrepreneurs, argue that electricity generated by wind and solar power will soon displace fossil fuels and give birth to a renewable energy economy. We wish this were true. But there are several reasons why those solutions will not replace carbon-based fuels on their own in time to save the planet. In our opinion, the best way to reduce CO2 emissions is to bury it in deep geologic formations. It may sound fanciful, but it’s actually easy to do. And in fact, the process is simply the oil and gas business in reverse.

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Read the opposing view.
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Larry O’Hanlon’s blog: Earth Impacts

A few words on why renewable energy solutions alone will not do the job. Although they beat out carbon-based fuels when it come to environmental and security-related criteria, fossil fuels still out-perform renewable options on nearly all other measures. For example, fossil fuels beat renewable energy on cost and energy density. A modern coal-fired power plant, for example, will generate electricity for less than $50 per megawatt-hour. The same quantity of electric energy can be generated from wind and solar for about $120 and $250, respectively. And fossil fuels are much easier to store as gas or fluid than the electricity produced from renewable sources, which must be saved in batteries. For comparison, the best batteries store just 1 to 2 percent of the energy per unit mass as crude oil.

This doesn’t mean that we should stop pursuing the use of renewable energy. It does mean that we need to be realistic about what can be done to reduce CO2 emissions now. We think the biggest potential lies with CO2 that is produced at power plants and certain chemical facilities. These large, stationary sources spew about 50 percent of all CO2 emissions into the atmosphere. If we could capture that gas at the source and bury it in porous rock deep underground, we could, in principle, reduce global CO2 emissions by about 50 percent without decreasing current use of fossil fuels.

Capturing and permanently storing CO2 in permeable rock requires three steps. First, the CO2 must be separated from other gases. Many industrial processes have been developed and proven in other industries to do this. The natural gas processing industry, for example, has developed systems for separating CO2 from methane.

Second, the CO2 must be transported by pipeline to the permeable rock underground. The oil and gas businesses already have substantial experience with moving compressed fluids through pipelines, so the transportation of CO2 can be readily accomplished.

Finally, the CO2 must be injected into a geologic formation that will retain it for millennia. Here again, we need not look farther than the oil business. They already use a process called enhanced oil recovery that involves injecting CO2 into oil reservoirs deep underground. The gas decreases the surface tension between oil and water in the reservoir, freeing up oil for extraction. Enhanced oil recovery has been an active process in the industry for the last 30 years and so could be improved upon for CO2 storage.

So, we know how to capture CO2, how to transport it, and how to inject it into geologic formations. But, how do we know that the CO2 will stay in these formations for millennia? The story here is a bit more mixed, but the reality is that the same two mechanisms that have kept natural gas from escaping from its reservoirs for geologic time will also trap CO2. Those two factors include capillary forces and the type of rock. Picture a straw in a glass of Coca-Cola. After you sip through the straw, you might notice that the carbonated soft drink gets trapped in the straw. A similar thing happens underground, where capillary forces keep buoyant fluids from escaping. Gas is also physically trapped inside porous rock by layers of solid rock overhead. Think of it as a lid on a jar.

The bottom line is that although the CO2 that is injected into terrestrial geologic formations is buoyant and can escape if the formation is not appropriately confined, it’s well documented that sedimentary basins have retained many billions of tonnes of naturally occurring CO2 as well as trillions of tonnes of buoyant hydrocarbons for millions of years.

The only issue that remains is price. Nobody knows for certain how much all of this will cost because the integrated process of capturing, transporting and storing CO2 has not been estimated. It’s generally expected, however, that capturing and storing CO2 from a coal-fired power plant will increase the electricity generation costs by less than 50 percent. Given that traditional coal-fired power is currently less than half the price of wind power and about a quarter the price of solar power, coal-fired power with CO2 capture and storage will still be cheaper than renewable power options.

Avoiding dangerously high levels of atmospheric CO2 requires drastic emissions reductions from the power industry. Carbon capture and storage is technologically viable, it’s likely to be cheap compared to renewable energy options, and it capitalizes on an energy infrastructure that is already in place.

Now read an opposing view by Peter Montague, executive director of Environmental Research Foundation on page two.

The Mars Science Laboratory was scheduled to fly next year but will be postponed until 2011. The project has been dogged by cost increases and technical challenges, and the delay could add $400 million to the price tag, which is likely to top $2 billion.

“Trying for ‘09 would require us to assume too much risk, more than I think is appropriate for a flagship mission,” said NASA Administrator Michael Griffin.

It’s the second time in two years that NASA has been forced to postpone a Mars mission. Last year, the space agency delayed a planned 2011 launch of a $485 million Mars atmospheric probe by two years because of an unspecified conflict of interest in the selection process.

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Since Mars and Earth only pass close enough to launch probes every 26 months, NASA will fly the Mars Science Lab in 2011. Delivery delays and additional testing caused the project to fall several months behind schedule, NASA said.

The Mars Science Lab is billed as the most advanced spacecraft to probe the Martian surface. The size of a small sports utility vehicle, it will study whether the environment was habitable in Mars’ early history and will carry high-tech instruments to analyze rocks and soil in greater detail than previous surface missions.

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The implications of the shift are reverberating through the ecosystem in surprising ways — leading to overpopulation in some places and a skewed sex ratio in others. Those changes could spell trouble for the entire food chain.

“If [the trend] continues, it’s just going to get ugly,” said Fred Janzen, an evolutionary biologist at Iowa State University in Ames. “I’m definitely concerned.”

Janzen has been tracking painted and snapping turtles along the Mississippi River between Iowa and Illinois for more than two decades. Year after year, he used to watch as turtle moms started building nests around June 1. Then, in the late 1990s, females began to lay their eggs about a week earlier.

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“I thought, ‘Wow, that’s early,’” said Janzen. “This was really a change. And it kind of stayed that way. For almost a decade, it’s been getting earlier and earlier.”

Climate records show that winters in the area have grown substantially warmer during the same time period — by about 4 degrees Fahrenheit. Last year was the only exception: Temperatures were exceptionally cold, and turtles nested later than they had during the past decade.

Until now, scientists didn’t know what determines when turtles build their nests. Janzen’s data have not yet been published, but other work supports his conclusions that warmer weather is causing turtles to nest earlier.

In the Czech Republic, St. Nicholas Eve is celebrated Dec. 5, when the saint, accompanied by a good and bad angel, visits children, bringing gifts to those who have behaved. On Christmas Eve, families gather to enjoy a feast featuring baked carp and kuba (a barley, mushroom, onion casserole). Many Czechs fast the 24 hours before Christmas Eve. One tradition holds that those who abide by the fast may be lucky and witness a magical golden pig “dancing” on the wall!