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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10 police killed in Afghanistan suicide attack: official






KABUL: At least 10 policemen were killed and 18 others, mostly civilians, were wounded in a suicide attack Saturday in a crowded area of the northeast Afghan city of Kunduz, provincial authorities said.

The attacker, who was on foot, detonated his explosives next to a group of police officers, according to several sources.

"We have 10 dead, including the counter terrorism police chief and head of traffic police and their bodyguards," Sayed Sarwar Hussani, Kunduz police spokesman told AFP.

Thirteen civilians and five policemen were wounded in the blast, Hussani said, adding that the final death toll may rise.

The attack was "the work of the enemies of Afghanistan", he said, using a phrase common among Afghan officials to describe Taliban insurgents.

AFP could not immediately reach the Taliban for comment on the attack, which has so far not been claimed by any group.

Afghanistan's interior ministry and the provincial governor spokesman Enayatullah Khaleeq confirmed the toll.

According to the head of the Kunduz health department, Saad Mukhtar, 19 people in total were wounded in the attack, which police officials said took place around 5:20 pm, 12:50 GMT.

Such attacks have in the past been blamed on Taliban insurgents who are leading an 11-year insurgency against the US-backed government of President Hamid Karzai.

Taliban militants have stepped up their fight against Afghan troops as the country's forces are increasingly taking over security responsibility from US-led NATO troops.

Earlier Saturday, a suicide attacker on a bicycle killed two civilians in southeastern Afghanistan's Ghazni province, and on Friday a suicide bomber in a car attacked a NATO convoy in Afghanistan's strategic Kapisa province, killing at least five civilians and wounding 15 others.

Also this week a squad of Taliban suicide bombers attacked Kabul traffic police headquarters in the heart of the city, killing three police officers and wounding dozens others.

The attacks come at a crucial juncture for Afghanistan as US-led NATO troops are preparing for their withdrawal from the country by the end of 2014. Afghan and international observers have predicted a civil war could grip the country once foreign troops have pulled out.

- AFP/jc



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Oppo BDP-105: Not your average Blu-ray player



The Oppo BDP-105 Blu-ray, SACD, and DVD-Audio player



(Credit:
Oppo)


Even by Oppo's high standards the BDP-105 is an extraordinary Blu-ray player. Sure, it's loaded with up-to-the-second features -- 4K upscaling, 2D-to-3D conversion, and a high-quality USB 2.0 digital-to-analog converter -- but what really makes the Oppo special is the sound. Pop the cover and look inside and you'll see why. Most of the 17-pound component's chassis space is devoted to the audio circuitry. That's nice, but the audio advantages will be completely irrelevant if you connect the BDP-105 to your receiver with a HDMI cable (the digital-to-analog conversion would then be handled in the receiver). The 105 was designed for buyers still using older $1,000 or $2,000 receivers from the days before HDMI connectivity, that would like to hear the Blu-rays' high-resolution DTS Master Audio or Dolby TrueHD soundtracks at their best. Since the audio won't be transmitted over the HDMI cable, you would run audio cables between the 105's seven- or five-channel analog outputs and the AV receiver's analog inputs.



The BDP-105 has 7.1/5.1 analog output jacks



(Credit:
Steve Guttenberg/CNET)


Or you could forgo the receiver entirely and hook up the BDP-105 directly to a five- or seven-channel power amplifier. That approach would produce better sound quality, but would lack the connectivity, flexibility, and convenience of today's better receivers. Still, the BDP-105/power amp combo would sound better and be more powerful than most top-of-the-line receivers. The 105's connectivity options won't match any decent receiver, but its connectivity suite is a lot more extensive than most Blu-ray players. The Oppo has two HDMI inputs, so you can connect external devices such as set-top boxes and network streaming devices, three USB 2.0 ports, coaxial and optical digital inputs for satellite boxes, televisions, video-game consoles, etc., and there's a built-in headphone amplifier. The BDP-105's extensive bass management options are on par with a lot of AV receivers. The player's digital volume control is easy to use.


For my listening tests, I hooked up the BDP-105 ($1,199) with an assortment of self-powered Audioengine and Emotiva monitor speakers, and a Hsu subwoofer. With this setup I didn't need to use an AV receiver or separate power amp, but the Raconteurs' "Live at Montreux" Blu-ray was vivid and very live sounding. The system's freewheeling dynamics were really impressive, and the surround mix on King Crimson's "Red" DVD-A projected a remarkably seamless wrap-around soundstage. Each instrument was precisely focused in a near 360-degree sound environment.



The BDP-105 has full speaker setup and bass management options, just like an AV receiver.



(Credit:
Steve Guttenberg/CNET)


Classical music on SACD was just as impressive, the front three speakers produced a three-dimensional soundstage with lots of depth, and string tone was top notch. Dramatic movies on Blu-ray and DVD sounded great. I plugged headphones into the BDP-105, but the sound wasn't special, Schiit Audio's $99 Magni headphone amp was a lot better.


The $499 Oppo BDP-103 shares most of the BDP-105's features, but lacks the upgraded digital-to-analog converters, so if you're planning on using HDMI to connect the player to your receiver, buy the 103, and save $700. You can use the 103's 7.1 analog outputs with an old high-end receiver lacking HDMI connectivity, but the 103's digital converters are a step down from the ones in the 105.


The BDP-105 is an update of the Oppo BDP-95, and the new one has lots of features the old player lacks, but the two players sound about the same. Oppo still has 95s in stock and sells them for $799.


Oppo sells direct and offers a 30-day money-back guarantee, and the return shipping is free.


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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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Cops Using More Private Cameras to Nab Suspects













Philadelphia detectives were able to quickly make an arrest in the murder and burning of a female pediatrician by viewing surveillance video of nearby stores and a hospital that captured the suspect entering the doctor's home and later getting into his truck.


In the hours after Dr. Melissa Ketunuti's body was found strangled and burning in her basement, city's Homicide Task Force collected surveillance footage from a coffee shop, drug store and hospital overlooking Ketunuti's block. It was footage taken from Ori Feibush's coffee shop that allowed cops to identify Smith.


The suspect, an exterminator named Jason Smith, soon confessed to detectives, police said.


Lately a range of crimes have been solved by the seemingly ubiquitous security videos maintained by private companies or citizens, and investigators have been able to quickly apprehend suspects by obtaining the video, deftly turning private cameras into effective police resources.








Philadelphia Police Arrest Suspect in Doctor's Killing Watch Video









Pa. Doctor Killing: Person of Interest in Custody Watch Video







Private surveillance cameras have become so pervasive that the face of a suspect who allegedly shot a Bronx, N.Y., cab driver in a botched robbery on Jan. 14 was splashed throughout the media within days because the cabbie had rigged his vehicle with a camera.


The New York Police Department arrested Salvatore Perrone after he was caught on surveillance video recorded near two of three shopkeeper slayings in Brooklyn, N.Y., in November. He has since been charged with murder.


And in Mesa, Ariz., surveillance footage taken in November by resident Mitch Drum showed a man rolling on the ground trying to extinguish flames that had engulfed his shirt, which had caught fire while he was allegedly siphoning gas from a car by Drum's house. The man was arrested.


Though surveillance cameras have been a staple of security since a network of government operated cameras dubbed the "ring of steel" was introduced in London in the early 1990s, police have recently launched programs to partner with more businesses.


In Philadelphia, police have launched a program for businesses to register private cameras with the department. According to the SafeCam website, businesses will only be contacted when there is a criminal incident in the vicinity of the security camera. At that point, police will request a copy of the footage for their investigation.


"Businesses are saying, 'I have a camera at this location, and it may or may not be of use to you. It's a registration to say, 'feel free to call me,'" Sgt. Joseph Green told ABCNews.com






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



Sandrine Ceurstemont, editor, New Scientist TV






We no longer have to imagine elephant seals feasting in the deep sea. An underwater camera has filmed one slurping up a hagfish, the first sighting of seal predation on the sea floor.







The event was captured by a Neptune Canada live video stream in the north-east Pacific Ocean and spotted by a teenager who was watching the feed. Marine mammal experts later identified the moustached face in the corner of the frame as an elephant seal, one of the few seal species that spends most of its time underwater. In this case, it was observed at a depth of 894 metres, but the animals can descend more than 1500 metres below the surface, holding their breath for longer than 100 minutes.



The sighting shows the value of citizen science: Steven Mihály from Ocean Networks Canada, based in Victoria, British Columbia, says that although data-mining techniques could be used to sift through the reams of underwater video, human observers are still most effective at picking out events of interest.



If you enjoyed this post, see a submerged hippo stay upright in a water tank or watch an underwater volcano spew exotic lava.




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US scholar urges dramatic rethink on Taiwan






WASHINGTON: With Beijing growing in strength, a US scholar is calling for a major rethink on Taiwan in which the island would cut its troop numbers in half and rebrand its army as a self-defence force.

The proposal marks a rare break from the conventional view of American and Taiwanese policymakers that the island needs to close the military gap with Beijing, but its author said an opposite course could strengthen Taipei.

Scott Bates, president of the Washington-based Center for National Policy, said the balance was "irretrievably shifting" in China's favor and it was politically and economically unrealistic that Taiwan would commit enough to close the gap.

Instead, Taipei can take the lead by halving the size of its army, rebranding it as a Self-Defence Force in the style of Japan and renouncing any military action on mainland China's soil, he argued.

"If Taiwan were to take a bold step like this, that would change perceptions on the mainland and perhaps win some popular support for the Taiwanese position," said Bates, a former congressional aide.

"If there were a showdown, it might make (Beijing) think twice."

Taiwan should turn the new force into a disaster response team ready to deploy throughout Asia and also highlight the island's democracy through a major initiative that supports civil society across the continent, Bates said.

And instead of waging a battle to preserve a dwindling number of nations' recognition of Taipei instead of Beijing, Taiwan can use its diplomatic resources to seek solutions on Asia's bitter territorial disputes, he said.

The new Taiwanese approach would give the island the moral high ground, winning over global opinion and ensuring that China would appear to be the aggressor if it attacked, he argued.

"Mainland Chinese public opinion is beginning to matter more. The Chinese Communist Party cannot ignore its own people without repercussions," Bates said.

China considers Taiwan to be a territory awaiting reunification, by force if necessary. China's defeated nationalists fled to Taiwan after defeat by the communists in 1949, with the island developing into a self-ruling democracy.

The United States switched recognition from Taipei to Beijing in 1979 but at the same time Congress passed the Taiwan Relations Act, which requires Washington to provide the island with means to defend itself.

Bates said that his proposal would complement efforts by Taiwan President Ma Ying-jeou, who has sought to ease tensions with China by expanding economic ties, though domestic critics accuse Ma of jeopardising the island's de facto independence.

Bates supported the continuation of the Taiwan Relations Act, saying the island needed a credible deterrent. While cutting its army, Bates called for Taiwan to launch a major upgrade of its air defences and navy to show that any effort to gain supremacy over the island would be costly.

The Taiwan Relations Act enjoys virtually unanimous support in the US Congress, where lawmakers have pressed President Barack Obama to sell to the island new F-16 jets - a step that China strongly opposes.

Bates' ideas, however, are unlikely to win quick support.

Joseph Bosco, a former Pentagon official, sharply criticised the proposal, saying it went against accepted concepts of deterrence and that Taiwan already had the moral high ground.

"Taiwan does not need to disarm unilaterally in order to prove its moral or political legitimacy," Bosco said on Wednesday at an event where Bates presented his proposal.

Bates, who spoke last year at Taiwan's National Defence University and wrote an opinion piece in the Taipei Times, said he wanted to start a debate.

"It doesn't have to be my plan, but there does have to be a strategic rethink," he said.

- AFP



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Samsung unveils rugged Galaxy phone for the outdoor type



Galaxy Xcover 2



(Credit:
Samsung)


Samsung has created a new smartphone that can handle the great outdoors and even spend time underwater.


Announced today, the Galaxy Xcover 2 is built as a durable and rugged device, according to Samsung. The phone is both dustproof and sandproof.


It can also hold its breath underwater, at least at a depth of around three feet for up to 30 minutes. You probably won't be making too many phone calls under the water, but the Xcover 2's camera can come in handy if you want to snap photos of life under the sea.


The phone provides Google map information and an enhanced GPS/GLONASS feature. Combing both the U.S.-based GPS and Russia's GLONASS can track your location more accurately, according to Samsung.


The camera's LED flash is bright enough so it can be used like a torch in dark conditions. The 1,700mAh battery boasts a capacity of 570 hours. To get in shape, the phone includes a Cardio Trainer Pro app so you can set up and monitor a personalizing training program.



Outfitted with
Android 4.1 Jelly Bean, the Xcover 2 is powered by a 1GHz dual-core processor. The 4-inch screen offers a WVGA display.


A 5-megapixel autofocus camera is found in the back, while a VGA camera faces front. The phone is equipped with Bluetooth version 4.0, which Samsung says can detect other Bluetooth devices up to 164 feet away.


Samsung has not yet announced where or when the phone will be available, nor how much it will cost. But the timing is right for the company to show off the Xcover 2 and reveal more details at next month's Mobile World Congress in Barcelona.


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8 Other Nations that Send Women to Combat


As the Pentagon works to figure out precisely how it will integrate women into military specialties previously closed to them—including infantry and artillery units—top U.S. defense officials are actively studying other militaries around the globe that have already sent women to combat.

The review includes researching the experiences of Australia, Canada, and other nations with whom American troops have worked closely in Iraq and Afghanistan, according to a senior Pentagon official. Some countries have had "three to ten years to go through this process, to integrate women" into combat roles, the official said.

There are roughly a dozen nations that have opened "close combat roles" to women. Those roles are defined by a 2010 British Ministry of Defense (MOD) study as those that include "engaging an enemy on the ground ... while being exposed to hostile fire and a high probability of physical contact with the hostile forces personnel."

In many parts of the world, these efforts have moved quickly once they've begun. Though women in Poland were not even accepted at the nation's military academies until 1999, for example, the country passed a law in 2004 requiring women with college nursing or veterinary degrees to register for compulsory service.

Of the dozen or so countries that allow women to be part of combat units, here are those with the fewest restrictions on what women can do:

Australia: Aside from the U.S., this is the country to most recently remove barriers to its front-line units, provided women meet the physical requirements. In 2011, Australia's defense minister announced that the last 7 percent of positions that had been closed to women—including Special Forces, infantry, and artillery—would be opened up to them.

Driven in large part by a string of sex scandals, the move includes a 5-year transition plan. At its height, Australia had more troops in Afghanistan than any non-NATO country, and women currently account for roughly 10 percent of all Australia's deployed troops.

Canada: In 1989 Canada opened all combat roles except those involving submarine warfare to women. In  2000, women were given the green light to serve on subs as well. Three years later, the first female was assigned to serve as captain of a Canadian warship, while another woman became the first female deputy commanding officer of a combat arms unit.

Roughly 15 percent of Canadian military forces are now women, while 2 percent of combat troops (99 troops) are female. In 2006, Canada lost its first female soldier—a forward artillery scout—in combat with Taliban forces.

Denmark: Since 1988, Denmark has had a policy of "total inclusion," which came on the heels of 1985 "combat trials" exploring the capabilities of women to fight on the front lines. "Danish research showed that women performed just as well as men in land combat roles," according to the British MOD study. Although all posts are open to women, physical requirements have so far prevented them from joining the country's Special Operations Forces.

France: Women make up nearly one-fifth of the French military and can serve in all posts except on submarines and in the riot-control gendarmerie. Though permitted to serve in the combat infantry, however, most chose not to. As a result, women make up only 1.7 percent of that force.

Germany: In 2001, the country opened German combat units to women, dramatically increasing the recruitment of female soldiers into the ranks. The number of women in the German Armed Forces is now three times as high as in 2001. As of 2009, roughly 800 female soldiers were serving in combat units.

Israel: In 1985 the Israeli Defense Force (IDF) began putting women into combat positions and by 2009 women were serving in artillery units, rescue forces, and in anti-aircraft forces. While women must take part in compulsory military service, they are conscripted for only two years, versus three for men.

A study on the integration of female combatants in the IDF between 2002 and 2005 found that women often exhibit "superior skills" in discipline, motivation, and shooting abilities, yet still face prejudicial treatment stemming from "a perceived threat to the historical male combat identity."

New Zealand: Women have been able to serve in all defense units, including infantry, armor, and artillery units, since the country passed a law to that effect in 2001. A report four years later found that the move helped drive a societal shift that "values women as well as men," but that the integration of women into the combat trades "needed a deliberate and concerted effort." The British MOD report concluded that there has been "variable success in attracting and recruiting women to these areas."

Norway: In 1985, Norway became the first country in NATO to allow women to serve in all combat capacities, including submarines. Norwegian women are also subject to the draft in the event of a national mobilization. "The few women that are attracted by the infantry and cavalry do a great job in the Norwegian Army," says Col. Ingrid Gjerde, an infantry officer in the Norwegian military for 25 years.

"I have to be clear: You have to meet the physical standards, because the job is still the same. It works very well as long as women hold the standards," added Colonel Gjerde, who was the commander of Norwegian forces in Afghanistan in 2012. "It's not a big deal because women who go into these fields know the standards, and it's not that hard for women to train up to the standards if they really want."


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Mars Rover Celebrates Milestone on Red Planet













It was never supposed to last this long. When the Mars rover Opportunity settled on the Martian surface nine years ago today, mission managers at NASA said they would be pleased if it lasted for 90 days.


Instead, it's been 3,201 days, and still counting. The rover has driven 22.03 miles, mostly at a snail's pace, from one crater to another, stopping for months at a time in the frigid Martian winters. The six motorized wheels, rated to turn 2.5 million times, have lasted 70 million, and are all still working.


"Opportunity is still in very good health, especially considering what it's gone through," said John Callas, manager of NASA's Mars Exploration Rover project. The surface of Mars is a pretty tough place; there can be temperature fluctuations of a hundred degrees each day. That's pretty hard on the hardware."


Video: '7 Minutes of Terror: A Landing on Mars


When Opportunity and its twin rover, Spirit, reached Mars in January 2004, there was a fair bit of sniping that NASA, with all that 90-day talk, was playing down expectations. It escalated when Steve Squyres of Cornell University, the principal investigator for the missions, said things like, "We're on Sol 300 of a 90-Sol mission." (A Sol is a day on Mars, and lasts 24 hours, 39 minutes.) Callas and others have insisted that the prediction was based on engineering, not a nod to public relations.










"There was an expectation that airfall dust would accumulate on the rover, so that its solar panels would be able to gather less electricity," said Callas. "We saw that on Pathfinder," a small rover that landed on Mars in 1997." The cold climate was also expected to be hard on the rovers' batteries, and changes in temperature from night to day would probably pop a circuit or two.


Instead, the temperatures weren't quite as tough as engineers had expected, and the rovers proved tougher. They did become filthy as the red Martian dust settled on them, reducing the sunlight on the solar panels -- but every now and then a healthy gust came along, surprising everyone on Earth by cleaning the ships off.


Click Here for Pictures: Postcards From Mars


Spirit, in hilly territory on the other side of the planet, finally got stuck in crusty soil in 2009, and its radio went silent the next year. But Opportunity, though it's had some close calls, is -- well, you remember those commercials about the Energizer bunny.


So what do you do with an aging rover on a faraway planet? You keep using it. In its first weeks, NASA said Opportunity found chemical proof that there had once been standing water on the surface of Mars -- good news if you're looking for signs that the planet could once have been friendly to life. Since then, it's been sent to other places, with rocks and soil that are probably older, and with clay that may have been left by ancient rivers.


About 20 NASA staff members still work full-time on Opportunity at the Jet Propulsion Laboratory in Pasadena, Calif. Another 60 split their time between Opportunity and other projects, such as the Curiosity rover that landed last August. About 100 scientists, doing research on Mars, pop in and out.


In a few months, Callas said, Opportunity will head to an area nicknamed Cape Tribulation. The clay there could be rich in the minerals suggestive of past life.


They haven't done much to mark the ninth anniversary or the 3,200th Martian day, just a get-together earlier this week during a previously scheduled science conference. After that, Callas said, it was back to work.


"It's like keeping your car going," he said, "without ever having a chance to change the oil."



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