Get cirrus in the fight against climate change

FEATHERY cirrus clouds are beautiful, but when it comes to climate change, they are the enemy. Found at high-altitude and made of small ice crystals, they trap heat - so more cirrus means a warmer world. Now it seems that, by destroying cirrus, we could reverse all the warming Earth has experienced so far.

In 2009, David Mitchell of the Desert Research Institute in Reno, Nevada, proposed a radical way to stop climate change: get rid of some cirrus. Now Trude Storelvmo of Yale University and colleagues have used a climate model to test the idea.

Storelvmo added powdered bismuth triiodide into the model's troposphere, the layer of the atmosphere in which these clouds form. Ice crystals grew around these particles and expanded, eventually falling out of the sky, reducing cirrus coverage. Without the particles, the ice crystals remained small and stayed up high for longer.

The technique, done on a global scale, created a powerful cooling effect, enough to counteract the 0.8 °C of warming caused by all the greenhouse gases released by humans (Geophysical Research Letters, DOI: 10.1002/grl.50122).

But too much bismuth triiodide made the ice crystals shrink, so cirrus clouds lasted longer. "If you get the concentrations wrong, you could get the opposite of what you want," says Storelvmo. And, like other schemes for geoengineering, side effects are likely - changes in the jet stream, say.

Different model assumptions give different "safe" amounts of bismuth triiodide, says Tim Lenton of the University of Exeter, UK. "Do we really know the system well enough to be confident of being in the safe zone?" he asks. "You wouldn't want to touch this until you knew."

Mitchell says seeding would take 140 tonnes of bismuth triiodide every year, which by itself would cost $19 million.

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French-led forces retake key north Mali town

BAMAKO: French-led troops recaptured the Islamist stronghold of Gao on Saturday, in a major boost to their 16-day-old offensive against Al Qaeda-linked rebels holding Mali's vast desert north.

France's Prime Minister Jean-Marc Ayrault said the nation's troops were also advancing on Timbuktu, another key northern town held by the insurgents.

The seizure of Gao, the most populated town in Mali's northern region, which is roughly the size of Texas, was announced by the French defence ministry and confirmed by Malian security sources.

France said troops from Niger and Chad "will pick up the baton" and that the mayor of Gao, Sadou Diallo, was due to return from the capital Bamako, 1,200 kilometres (750 miles) to the southwest.

"A first contingent of Malian, Chadian and Niger troops are presently in Gao to help secure it," a Malian security source told AFP by telephone from the town. They had been flown in from Niamey, capital of neighbouring Niger.

"The French and African forces are in 100-percent control of the town of Gao," another Malian security source said. "There is popular rejoicing and everyone is very happy."

Other soldiers from Chad and Niger meanwhile were moving toward the Malian border from the Niger town of Ouallam, which lies about 100 kilometres southeast of Gao.

French-led forces had overnight Friday seized Gao's airport and a key bridge on the southern entrance of the town, held by the Al Qaeda-linked Movement for Oneness and Jihad in West Africa (MUJAO).

There had not been substantive fighting around Gao, said a spokesman for the French military command, but there was some sporadic gunfire from "terrorist elements".

Defence ministry sources in Paris described as "plausible" a report in the Le Monde, citing military sources, that hundreds of Islamists had died since the French military intervention in Mali.

In April last year after a coup in Bamako, an alliance of Tuareg rebels who wanted to declare an independent homeland in the north and several hardline Islamist groups seized Gao, Timbuktu and Kidal.

The Islamists quickly sidelined the Tuaregs and imposed their harsh interpretation of Islamic sharia law. Transgressors were flogged, stoned and executed, they banned music and television and forced women to wear veils.

The Islamist groups include Al-Qaeda in the Islamic Maghreb (AQIM); the MUJAO, which is an offshoot of AQIM; and homegrown Islamist group, Ansar Dine.

French Prime Minister Jean-Marc Ayrault said the troops were currently "around Gao and (will be) soon near Timbuktu," further to the west. A fabled caravan town on the edge of the Sahara desert, for centuries it was a centre of Islamic learning.

"The objective is that the African multinational force being put together be able to take over, and that Mali be able to begin a process of political stabilisation," he said.

The MUJAO meanwhile said it was ready for negotiations to release Gilberto Rodriguez Leal, a French national of Portuguese origin kidnapped in western Mali in November.

But Ayrault snubbed the offer. "We will not give in to blackmail," he said.

"We cannot cede to terrorism because if this is the case they will win every time."

West African defence chiefs meanwhile reviewed the slow deployment of regional forces to bolster the French-led offensive at an emergency meeting in Ivory Coast boosting their troops pledges to 5,700 from the previous 4,500.

Chad, which neighbours Mali but is not a member of the Economic Community of West African States raising that force, has separately promised 2,000 soldiers.

A fraction of the African forces has arrived in Bamako, the Malian capital in the south of the country, and is slowly deploying elsewhere. So far however, the French and Malian forces have done all the fighting.

France has already deployed 2,500 troops to Mali and its defence ministry says 1,900 African soldiers are already on the ground there and in Niger.

Aid agencies have expressed concern about the growing food crisis for civilians in the vast semi-arid north of Mali and the drought-stricken Sahel as a whole.

- AFP/fa

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The ultimate gall of a heartless iPhone thief

An object of desire?

(Credit:
CNET)

One should never expect justice in life.

The best one can hope for is poetry.

And yet, just once or twice, both manage to collide with a deliciousness that moves the soul.

Here is the tale of a teenage girl who had her iPhone stolen.

As The New York Times composes it, the girl had her
iPhone 4S ripped from her by a teenage boy in Brooklyn's notoriously difficult Prospect Park.

iPhone theft is rather popular in New York. Indeed, Mayor Bloomberg recently suggested that it's responsible for an increase in crime in the city.

Anyway, the iPhone-less girl collared a couple of policemen, but the miscreant was not to be found.

However, the thief then decided that he'd try to get some money for the phone. So he met a man on a Flatbush street -- as you do.

The man asked to take a look at the phone. Perhaps he wanted to see whether Siri was still inside.

Then, he ran off with it.

Yes, this is slightly poetic. But we've only just begun.

You see, the boy thief was not very happy. After all, he'd had his recently acquired property stolen. So he went off in search of a policeman to report the crime.

I pause for your sound effects.

Thank you.

More Technically Incorrect

The police reacted with unusual efficiency. They corralled both the boy and the man who had taken Siri from him. But they still assumed the boy was the victim.

Are you ready for verse three?

The phone rang. It was the girl trying to do a deal to get her phone back. The police realized something might be amiss here. This seemed to be a miss who actually owned the phone.

So they waited for her to arrive in Flatbush. She recognized the boy's sneakers. They were pink.

I pause for your further sound effects.

The police decided it was time to play Solomon. They would slice the phone in two if one party didn't renounce their claim to the phone.

No, wait. They asked both the girl and the pink-sneakered boy to unlock the phone with the PIN code.

You're already there, aren't you? Both the actual thieves were brought to justice -- the actual kind. And the girl got her phone back.

There are several morals to this story.

One, don't steal iPhones if you're wearing pink sneakers.

Two, if someone does unto you as you have done unto someone else, take it onto the chin. It will help you understand the feelings of others.

Three, if you're the kind of New Yorker who thinks they can always get away with it, well, you can't. Not always.

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Pictures: The Story Behind Sun Dogs, Penitent Ice, and More

Photograph by Art Wolfe, Getty Images

If you want the beauty of winter without having to brave the bone-chilling temperatures blasting much of the United States this week, snuggle into a soft blanket, grab a warm beverage, and curl up with some of these natural frozen wonders.

Nieve penitente, or penitent snow, are collections of spires that resemble robed monks—or penitents. They are flattened columns of snow wider at the base than at the tip and can range in height from 3 to 20 feet (1 to 6 meters). The picture above shows the phenomenon in central Chile. (See pictures of the patterns in snow and ice.)

Nieve penitente tend to form in shallow valleys where the snow is deep and the sun doesn't shine at too steep an angle, said Kenneth Libbrecht, a physicist at the California Institute of Technology in Pasadena who studies ice crystal formation.

As the snow melts, dirt gets mixed in with the runoff and collects in little pools here and there, he said. Since the dirt is darker in color than the surrounding snow, the dirty areas melt faster "and you end up digging these pits," explained Libbrecht.

"They tend to form at high altitude," he said. But other than that, no one really knows the exact conditions that are needed to form penitent snow.

"They're fairly strong," Libbrecht said. "People have found [the spires] difficult to hike through."

—Jane J. Lee

Published January 25, 2013

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Newtown Families March for Gun Control in DC

Jan 26, 2013 4:59pm

(YURI GRIPAS/AFP/Getty Images)

WASHINGTON, D.C. — Near-freezing temperatures didn’t stop several thousand gun-control activists from bearing their pickets today, carrying signs emblazoned with “Ban Assault Weapons Now” and the names of gun violence victims in a demonstration organized as a response to the mass shooting in Newtown, Conn. last month.

Walking in silence, the demonstrators trudged between Capitol Hill and the Washington Monument over a thin layer of melting snow. They were joined by politicians and some families of the Newtown victims.

March organizer Shannon Watts said the event was for the “families who lost the lights of their lives in Newtown, daughters and sons, wives and mothers, grandchildren, sisters and brothers gone in an unfathomable instant.”

“Let’s stand together and use our voices, use our votes to let legislators know that we won’t stand down until they enact common sense gun control laws that will keep our children out of the line of fire,” she told demonstrators.

Watts founded One Million Moms for Gun Control after the killing of 20 first graders and six adults at the Sandy Hook Elementary School in Newtown in December. In a profile with the New York Times, Watts said her 12-year-old son had suffered panic attacks after learning of last summer’s Aurora, Colo., theater shooting, leaving her at an impasse over how to talk to him about the latest tragedy.

Also among the speakers was a survivor of the 2007 Virginia Tech massacre, Collin Goddard.

“We need to challenge any politician who thinks it’s easier to ask an elementary school teacher to stand up to a gunman with an AR-15 than it is to ask them to stand up to a gun lobbyist with a checkbook,” he said.

The demonstration comes amid a push by progressive lawmakers to enact stricter gun control measures as a response to the trend of recent mass killings, although any hypothetical bill would likely face strong opposition in Congress.

Rep. Chris Van Hollen, D-Md., was among the demonstrators today.

“The idea that people need high-capacity magazines that can fire 30, 50, 100 rounds has no place in a civilized society,” he said. “Between the time we’re gathered here right now and this time of day tomorrow, across America, 282 Americans will have been shot.”

The congressman was quoting statistics compiled by the Brady Campaign to Stop Gun Violence.

INFOGRAPHIC: Guns by the Numbers

Last week President Obama proposed a sweeping overhaul of federal measures regulating gun ownership, including a universal background check system for sales, banning assault weapons,  and curbing the amount of ammunition available in weapon clips.

An ABC News/Washington Post poll released Thursday found 53 percent of Americans viewed Obama’s gun control plan favorably, 41 percent unfavorably. The division was visible today, as a handful of gun-rights advocates also turned out on the National Mall to protest what they believe would be infringements on their Second Amendment liberties.

ABC’s Joanne Fuchs contributed to this report.

SHOWS: Good Morning America World News

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Today on New Scientist: 25 January 2013

Hagfish gulped up in first video of deep-sea seal hunt

Watch the first sighting of a seal's underwater eating habits spotted by a teenager watching a live video feed

World's oldest portrait reveals the ice-age mind

A 26,000-year-old carved ivory head of a woman is not just an archaeological find - a new exhibition in London wants us to see works like this as art

Dung beetles navigate using the Milky Way

Forget the Pole Star: on moonless nights dung beetles use the Milky Way to follow a straight path with their dung ball

Stress's impact can affect future generations' genes

DNA analysis has yielded the first direct evidence that chemical marks which disable genes in response to stress can be passed on to offspring

Uncharted territory: Where digital maps are leading us

The way we use maps is evolving fast, says Kat Austen, and it will change a great deal more than how we navigate

Feedback: Tales of the stony turd industry

Fossilised faeces in Shitlington, confusing railway notices, organic water, and more

Duolingo gives language learning a jump start

First evidence that Duolingo, a new website that helps you learn a language while translating the web, actually works

Dolphins form life raft to help dying friend

A group of dolphins was caught on camera as they worked together to keep a struggling dolphin above water by forming an impromptu raft

Zoologger: Supercool squirrels go into the deep freeze

Hibernating Arctic ground squirrels drop their body temperatures to -4 °C, and shut their circadian clocks off for the winter

Greek economic crisis has cleared the air

The ongoing collapse of Greece's economy has caused a significant fall in air pollution, which can be detected by satellites

Body armour to scale up by mimicking flexible fish

Armour that is designed like the scales of the dragon fish could keep soldiers protected - while still letting them bend

Astrophile: Split personality tarnishes pulsars' rep

Pulsars were seen as cosmic timekeepers, but the quirky way in which one example shines suggests we can't take their behaviour for granted

Shrinking proton puzzle persists in new measurement

The most precise experiment yet to find the proton's radius confirms that it can appear smaller than our theories predict - is new physics needed?

Tight squeeze forces cells to take their medicine

A short sharp squash in these channels and a cell's membrane pops open - good news when you want to slip a molecule or nanoparticle in there

Read More..

Apple co-founder says Steve Jobs film inaccurate

LOS ANGELES: Apple co-founder Steve Wozniak said on Friday that a new film about the late Steve Jobs is factually "wrong," while the movie's makers countered it is meant as entertainment -- not a literal retelling of the computer pioneer's life.

Wozniak said the movie "jOBS -- which premiers Friday at the Sundance Film Festival -- erred in its depiction of the characters as well as the relationships between them -- especially the one between him and Jobs.

"We never had such interaction and roles," Wozniak, who quit Apple in 1987 after 12 years, told the tech blog Gizmodo.

"I'm not even sure what it's getting at," he said, adding that the "personalities are very wrong -- although mine is closer."

"The ideas of computers affecting society did not come from Jobs. They inspired me and were widely spoken at the Homebrew Computer Club," he said, referring to a hobby group to which they belonged.

The film, one of two about the iconic Apple founder who died in 2011, is due for release in the United States in April.

"Steve came back from Oregon and came to a club meeting and didn't start talking about this great social impact," said Wozniak, referring to the period in the 1970s before Silicon Valley took off.

"His idea was to make a $20 PC board and sell it for $40 to help people at the club build the computer I'd given away. Steve came from selling surplus parts at HalTed -- he always saw a way to make a quick buck off my designs," said the famously geek-casual-looking Wozniak.

"The lofty talk came much further down the line... I never looked like a professional. We were both kids," he said.

The film's producers responded to Wozniak's comments in a statement cited by Entertainment Weekly.

"The film is not a documentary, nor is it meant to be a blow-by-blow, word-for-word account of all conversations and events," it said.

"The filmmakers have tremendous admiration and respect for Wozniak and all those that are portrayed in the film, and did extensive research in an effort to make an entertaining accurate film that captures the essence and story of Steve Jobs and those that built Apple with him," the statement said.

But the filmmakers acknowledged "that not every single thing in the film is a precise representation of what took place."

The movie "is feature film entertainment about one of the most important, creative and impactful people," their statement added.

Wozniak, who made his criticism after seeing just one short movie clip, conceded that inaccuracies did not necessarily mean the film was bad.

"The movie should be very popular and I hope it's entertaining. It may be very correct, as well. This is only one clip," he said.

"But you'll see the direction they are slanting the movie in, just by the dialogue style of this script," he said.

He added: "Our relationship was so different than what was portrayed. I'm embarrassed. but if the movie is fun and entertaining, all the better. Anyone who reads my book 'iWoz' can get a clearer picture."

- AFP/fa

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Q&A: MacFixIt Answers

MacFixIt Answers is a feature in which I answer Mac-related questions e-mailed in by our readers.

This week, readers wrote in with questions about managing contact images in Address Book, the lowdown on the rather negative community reaction surrounding the MacKeeper utility, and errors in gathering Application information in the System Information utility. I welcome views from readers, so if you have any suggestions or alternative approaches to these problems, please post them in the comments!

Question: Managing the Recent section for contact images in Address Book
MacFixIt reader Lars asks:

Is there a way to get rid of the cache of "Recent" photos that appear in the left-hand column of the address book photo picking program? There seem to be so many "recent" photos in the app that I have a hard time finding what I am looking for. If you can help me delete that cache of photos it would be great.

Answer:
This can be done by selecting them and pressing the Delete key to remove them from the list. However, if this does not work you should still be able to clear the recent images by removing the contents of the following directory:

Users > username > Library > Containers > com.apple.ImageKit.RecentPictureService > Data > Library > Images > Recent Pictures

Question: The lowdown on the stigma surrounding MacKeeper
MacFixIt reader Janu asks:

I want to know, is it safe to use MacKeeper? Many of my friends are saying that it is malware.

Answer:
The issues surrounding MacKeeper stem from it starting out as a poor conversion from a utility called PC Keeper for Windows systems, one that didn't work very well on the Mac OS. This coupled, with rather aggressive (to say the least) marketing tactics and customer service, caused many in the
Mac community to avoid it and recommend that others do the same.

The software has been updated quite significantly since its initial versions and I've installed it without any problems on several systems. With regard to safety, any software package may contain bugs that can adversely affect a system. As a result, my stance on it is that MacKeeper is not the malware that some people describe it as, but whether or not it is necessary or beneficial -- or stable -- on any given computer is another matter.

MacKeeper ultimately offers many of the same features that are already available in other programs (many of which are free and arguably have used better coding). While I do not see a problem with the software itself, I don't necessarily recommend it for everyone.

My guess is that not all, but many, people in this community who are recommending avoiding or uninstalling MacKeeper are simply reiterating advice from others based on the software's poor initial track record, as opposed to truly testing and making an objective assessment of the latest versions of the software.

Question: Errors with gathering information in the System Information utility
MacFixIt reader Dany asks:

When I open System Information and go to Software > Applications, I get "There was an error while gathering this information". Can you help me to solve this issue, please? (iMac mid 2007 - OS X 10.8.2)

Answer:
Many of the features in the System Information tool rely on an intact index of the hard drive. The Applications list also relies on the "pbs" service, which reads application attributes and associated services they offer in OS X. Try opening the Terminal and running the following commands to clear these components so they'll be rebuilt, then restart the system and see if the problem persists (it may take an hour or so for the system to rebuild these services):

/System/Library/CoreServices/pbs -flush
mdutil -E /

---

Questions? Comments? Have a fix? Post them below or !
Be sure to check us out on Twitter and the CNET Mac forums.

Read More..

Pictures: The Story Behind Sun Dogs, Penitent Ice, and More

Photograph by Art Wolfe, Getty Images

If you want the beauty of winter without having to brave the bone-chilling temperatures blasting much of the United States this week, snuggle into a soft blanket, grab a warm beverage, and curl up with some of these natural frozen wonders.

Nieve penitente, or penitent snow, are collections of spires that resemble robed monks—or penitents. They are flattened columns of snow wider at the base than at the tip and can range in height from 3 to 20 feet (1 to 6 meters). The picture above shows the phenomenon in central Chile. (See pictures of the patterns in snow and ice.)

Nieve penitente tend to form in shallow valleys where the snow is deep and the sun doesn't shine at too steep an angle, said Kenneth Libbrecht, a physicist at the California Institute of Technology in Pasadena who studies ice crystal formation.

As the snow melts, dirt gets mixed in with the runoff and collects in little pools here and there, he said. Since the dirt is darker in color than the surrounding snow, the dirty areas melt faster "and you end up digging these pits," explained Libbrecht.

"They tend to form at high altitude," he said. But other than that, no one really knows the exact conditions that are needed to form penitent snow.

"They're fairly strong," Libbrecht said. "People have found [the spires] difficult to hike through."

—Jane J. Lee

Published January 25, 2013

Read More..

'Hot' Guns Fueling Crime, US Study Says

Christmas is the one day of the year that Wal-Mart is closed, but for a group of four New Mexico burglars, it was the perfect time to stop in for some firearms.

Video surveillance cameras caught the masked burglars red-handed, stealing rifle after rifle. Police arrested the four men, and were able to recover the guns. But all too often, stolen weapons end up in the hands of criminals.

The New Mexico caper is part of a flood of gun thefts nationwide. And it's not only commercial gun dealers vulnerable to theft.

Guns are a top target for home burglars looking for something they can easily sell on the street.

An estimated 230,000 guns per year are stolen in home burglaries and property crimes, according to a study by the Department of Justice.

"Any burglar that goes in a house and finds guns, their eyes are going to light up," says former ATF Assistant Director Mike Bouchard. "That's the first thing they're going to take."

The statistics for commercial thefts show that nearly 25,000 guns per year are lost or stolen from gun dealers.

According to the Bureau of Alcohol Tobacco and Firearms (ATF), more than 4,000 gun stores and retailers have been targeted in the last three years, with 74,000 guns reported stolen or lost. And criminals will use any method possible to get their hands on some weapons, either for their own use, or to sell on the black market.

Minnesota Public Radio, Jeffrey Thompson/AP Photo

Washington Teen Allegedly Helped Steal Father's Guns Watch Video

Obama on Gun Violence Measures: 'This Is Common Sense' Watch Video

Recently, thieves have taken to using a stolen vehicle to ram down the front doors of a gun store. In North Charleston, S.C., for example, burglars smashed a stolen truck right through Guns and Gold Trading Post, stealing $4,500 worth of guns before making a quick getaway.

"Gun stores are like candy stores for criminals," says Mike Bouchard.

2012 was a record year for gun sales, with more than 19.5 million background checks run for gun purchases, up almost 20% from the previous year. But while legitimate sales skyrocket, huge numbers of illegal guns are hitting the streets.

According to the Justice Department, more than 1.4 million guns were stolen or lost between 2005 and 2010.

Former ATF Assistant Director Bouchard says crooks have easy access to cheap stolen guns on the street.

"If you talk to any criminal, they can find a gun within an hour or two. Cheaper guns that were stolen can be sold for $50. On the street, a typical good handgun will run you $200 to $300," Bouchard said.

Some thieves have even targeted gun shipments, stealing the weapons before they get to market.

Last November, for example, a rogue truck driver allegedly stole a shipment of 111 guns he was supposed to deliver from the Smith and Wesson factory in Springfield, Mass.

When police caught him, they recovered 28 of the stolen guns, but some had already been used in crimes.

When police arrested the alleged stick-up robber known as the Black Jacket Bandit, they found one of the stolen guns was allegedly used by him in a convenience store robbery within weeks of the delivery heist.

In November, more than 100 powerful AK-47s were stolen from a rail yard in Atlanta. The guns were in a box car containing more than 1,000 guns being shipped from an overseas manufacturer to a major U.S. distributor, authorities say.

A few of the weapons have been recovered, but police are deeply concerned about having scores of new assault rifles falling into the wrong hands.

Given all the gun thefts, police say it is critical for gun owners to secure their weapons in gun safes or locked cases. And authorities are urging gun retailers to fortify their buildings, to try to prevent "smash and grab" type robberies.

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