Saturday, 19 December 2009

Johnald's Fantastical Daily Link Splurge

Johnald's Fantastical Daily Link Splurge

Dark Liquor Makes For Worse Hangovers

Posted: 18 Dec 2009 03:21 PM PST


A new study may help drinkers pick their poison. In a head-to-head comparison, bourbon gave drinkers a more severe hangover than vodka, report Damaris Rohsenow of Brown University and colleagues in an upcoming issue of Alcoholism: Clinical and Experimental Research.

sciencenewsBut vodka drinkers aren't off the hook: Drinkers' sleep suffered equally with both drinks, as did their performance on tasks requiring attention and quick responses. Understanding the lingering effects of alcohol after a night of heavy drinking is important for people who engage in safety-sensitive tasks, such as driving, while hung over Rohsenow says.

The researchers recruited 95 healthy young adults, ages 21 to 33, and gave them caffeine-free cola mixed with bourbon, vodka or tonic water. The drinking ended when participants' breath-alcohol concentrations hit an average of 0.11, well over the legal intoxication limit. Participants were then hooked up to sleep monitors, which record brain activity, and allowed to sleep it off. At 7 a.m. the next day, the researchers roused the subjects from bed (a wake-up that did not include coffee or aspirin) and asked them to rate the severity of their hangovers.

Overall, bourbon drinkers reported feeling worse than vodka drinkers, rating higher on scales that measure the severity of hangover malaise, including headache, nausea, loss of appetite and thirst. It should come as no surprise that alcohol drinkers said they felt much worse than those who had drunk only tonic water.

One reason for the different effects of vodka and bourbon, Rohsenow says, could be that bourbon contains 37 times more toxic compounds than vodka does, including nasty organic molecules such as acetone, acetaldehyde, tannins and furfural. A good rule of thumb for liquors, she says, is that the clearer they are, the less of these substances they contain.

Both the bourbon drinkers and vodka drinkers slept poorly compared to the nondrinkers, the team found. The next morning, when the participants performed cognitive tests that required attention and quick reaction times, the drinkers performed worse than the nondrinkers, but the type of alcohol had no effect on performance. Both groups of drinkers were impaired equally.

Image: Experiment_33/Flickr

Video: The Asteroid That Will Almost Hit Earth

Posted: 18 Dec 2009 11:51 AM PST

agu2009_bugSAN FRANCISCO — Any number of undiscovered near-Earth objects could one day careen into the Earth, and there is a lot of talk here at the American Geophysical Union meeting about tracking them. So far, though, only one discovered object has seemed even mildly likely to hit our planet.

That asteroid is Apophis, a 900-foot asteroid. Calculations released on Christmas Eve 2004 appeared to show that there was a greater than 2 percent chance the asteroid would hit the Earth in 2029. The asteroid appeared ready to give the Earth its closest shave since astronomers began looking for such things. It was judged a 4 on the Torino Impact Hazard Scale for a short time, the highest rating any near-Earth object has received.

As it turned out, more precise observations brought the risk of collision down to just 1 in 250,000, but the scare sparked greater interest and study in the fields of asteroid detection and defense.

Even though the asteroid doesn't look like it's going to hit Earth, on April 13, 2029, it will come closer to Earth than any other near-Earth object that we know of. It will pass just 18,300 miles above the planet's surface.

Here, we see an exclusive animation created by the Jet Propulsion Laboratory of what that approach will look like from the perspective of the asteroid. And whoo boy, does it seem close.

Video: NASA/JPL.

See Also:

WiSci 2.0: Alexis Madrigal's Twitter, Google Reader feed, and green tech history research site; Wired Science on Twitter and Facebook.

Increase in Shining Clouds Highlights Climate ‘Weirding’

Posted: 18 Dec 2009 11:17 AM PST

agu2009_bug SAN FRANCISCO — Shining clouds at the edge of space are growing in number and brightness. For years, scientists have puzzled over the observed increase in these noctilucent clouds.

Now two groups modeling the behavior of the atmosphere have found new support for the idea that human-induced climate change is the cause.

Their models, presented here at the American Geophysical Union meeting, accurately reproduced both the variability induced by the solar cycle and the intensification trend. The intensification is driven by changes in the atmosphere below the clouds, triggered by increasing amounts of greenhouse gases.

"They are showing that it's largely due to change farther down in the atmosphere," said John Plane, an atmospheric chemist at University of Leeds who was not involved with the work. "That's a really good thing because a lot of the rationale for studying these clouds is that you can use them as an early warning of climate change elsewhere in the atmosphere."

Noctilucent clouds are one of the atmosphere's strangest visible phenomena. As the sun goes down, these wispy clouds in the northern latitudes appear to glow as the ice particles in the clouds reflect the sun's rays. They aren't as dramatic as aurorae, but they are a distinct and mysterious phenomenon that's much more common now than it was when our great grandparents bought their first cars and switched on the lights for the first time.


The new work comes from two separate groups of scientists using different models of the atmosphere. One group, led by Daniel Marsh of the National Center for Atmospheric Research used the Whole Atmosphere Community Climate Model, which simulates how the various layers of the Earth's atmosphere respond to changes in chemistry and solar radiation. They were able to model the increasing amounts of ice mass at the level in the atmosphere where noctilucent clouds and a close cousin, polar mesospheric clouds, form.

"My model does reproduce the trend, and its drivers are the increasing methane and increasing CO2," Marsh said.

Marsh's work broadly agrees with that of Franz-Josef Lübken, an atmospheric physicist at the Leibniz Institute for Atmospheric Physics in Kühlungsborn, Germany. Lübken used the Leibniz Institute Middle Atmosphere Model, which looks just at the specific layer of the atmosphere where the glowing clouds appear. Lübken's also reproduced the variability and long-term increase in noctilucent clouds. His model implicitly takes increasing carbon dioxide into account because it's "nudged" by activity in lower layers where carbon dioxide is causing changes in atmospheric chemistry.

In 2003, a scientist at Lübken's own institution questioned whether noctilucent clouds [pdf] were a good indicator of global change. Physicist Gary Thomas, who had been one of the first to float the idea, concluded in a review of noctilucent cloud data that "longer time series and more comprehensive models are needed before the link with global change can be established."

And that's exactly what Marsh and Lübken presented here this week.

"The new thing is that we have this consistency between the models and observations as far as the [upward] trend is concerned, which had not been the case," Lübken said. "The past models hadn't been able to reproduce the trends because the microphysics that goes into them was not good enough."

The increase in noctilucent clouds appears to result from a decrease in temperature at the altitude where the clouds form along with an increase in water vapor. Warming in the in the layers of the atmosphere below the clouds actually causes the cloud layer to cool. The clouds only form under very specific circumstances, so small changes in the atmosphere can lead to large changes in the observed occurrence of the phenomenon.

"A very small temperature decrease, just 0.08 Kelvin per year, together with an increase in water vapor, causes a substantial increase in occurrence rates and brightness," Lübken told scientists here Wednesday.

There are still differences between the two models and details to be worked out. In Lübken's model, the temperature decrease is driven by the cooling of the stratosphere, which has long been a predicted impact of climate change induced by increasing carbon dioxide emissions. The increase in water vapor is a dynamic process caused by increased freeze drying of water particles a couple of miles up from where noctilucent clouds form. The atmospheric dynamics push more humidity to exactly the altitude at which the clouds form.

Marsh's model includes the dynamics of methane, which, as it breaks down in the upper atmosphere, creates more water vapor at higher altitudes. Lübken's does not, but the trend is still apparent, so it's unclear how important methane's role in the increase in noctilucent clouds is.

The clarity and similarity of the pattern coming from these two different models gives the greenhouse-gas hypothesis an edge over other explanations for the increase in noctilucent clouds, like an increase in water vapor driven by Space Shuttle launches.

Up next, Marsh will try to explain one of the most persistent and strange mysteries associated with noctilucent clouds. While historical astronomers and sky watchers reported seeing many of the phenomena we now know and understand, there are isn't a single account of a noctilucent cloud before 1885. It's unclear whether they just weren't there or people just weren't looking hard enough. The first descriptions of the clouds come two years after the eruption of Krakatoa, which caused spectacular sunsets and may have encouraged people to look up more often.

Marsh plans to run his model back in time to see if it can reproduce the appearance of the clouds in the 1880s solely in response to the increase of greenhouse gases in the atmosphere caused by coal-powered industrialization.

Images: 1) The sky over Omaha on July 14th./ Mike Hollingshead, Extreme Instability. 2) NASA.

See Also:

WiSci 2.0: Alexis Madrigal's Twitter, Google Reader feed, and green tech history research site; Wired Science on Twitter and Facebook.

Why Geologists Love Beer

Posted: 18 Dec 2009 03:00 AM PST

agu2009_bugSAN FRANCISCO — Fact: Geologists love beer.

There is abundant proof of this here at the American Geophysical Union meeting, the largest collection of earth scientists in the world.

The talks, workshopsand poster sessions go from 8:00 a.m. to 6:00 p.m., but at 3:30 p.m. every day, for five days, kegs of beer are rolled out into the meeting. The beer flows nonstop for an hour and a half at around 10 different stations, and AGU organizers tell me they go through about 175 kegs during the week.

"Every other convention assumes that if you have a beer, your brain goes soft," said Kathy Sullivan, who has been serving beer at the AGU meeting for 26 years."But not the geophysicists. They think if you have a beer, you can still learn things. So they do."

At the Thirsty Bear, the closest brewpub to the Moscone Convention Center where the annual meeting is held every December, the waitstaff claims this is the busiest week of the year for them.I heard from the Borehole Research Group at the Lamont Doherty Earth Observatory thatone server at the Thirsty Bear said the staffcan't take vacation days during the AGU meeting"because the geologists are coming."

So the real question is why the bond between geologists and beer is so strong. I decided to do some research this week to get to the bottom of the phenomenon.So, beer in hand,I asked a sampling of the16,000 or sogeologists, geophysicists, hydrologists and atmospheric scientists at the meeting and got some very interesting responses. (Full disclosure: I am also a geologist, and I like beer.)

The most popular theory was that itmust havesomething to do with the amount of time spent outside doing fieldwork.

"When it's hot, and you've been hiking all day carrying 50 pounds of rocks, do you want a Merlot?" asked thermochronologist Jim Metcalf of Syracuse University. "No."

"It goes down a lot easier than water because a lot of the places we go, we can't drink the water," said structural geologist Jonathan Gourley of Trinity College.

Geologists have been known to go to great lengths to chill their beer in the field, as well. A cold stream, a glacier or a patch of snow is handy, but many field areas are hot, dry and dusty. While doing field work in Mongolia, geologist Cari Johnson of the University of Utahand her colleaguescooled their beer with evaporationby wrapping the cans in toilet paper,pouring water on the paper and setting them out in the persistent wind to dry over and over until the beer was cold.

Another theory is that beer makes for better science. I think this hypothesis has some merit, but requires further investigation (as long as I'm not in the control group).

"Science doesn't work when people keep secrets and don't share their data," said Daniel Jaffe of the University of Washington."And what could be better to help with the free flow of information?"

Rick Saltus of the U.S. Geological Surveyexplained that because geologists often don't have enough data to say definitively what went on millions of years ago, creativity is needed to fill in the gaps.

"You have to think outside the box, you've got to release your inhibitions, and beer is one way to do that," Saltus said."Anything that helps you get to that epiphany, that realization of what's there in the rocks and not easy to see but there to spin a story from."

A third theory offered up in various forms is that beer is simply part of the culture, something that has been handed down from advisor to student for generations.

"It's accepted and encouraged to drink beer," said geologist Cindy Martinez of the American Geological Institute. "Other scientists like beer, but it's not necessarily socially acceptable to have your scientific meetings revolve around beer."

"I started getting on to wine and other stuff for a while, but I became an outcast among my geology friends," said geologist Laura Webb of the University of Vermont."So I had to retrain myself to drink brew."

Supporting the culturetheory is the observation that earth science departments at academic institutions across the world almost invariably have a weekly get-together of some sort that revolves around beer.

At Stanford University, it's called Friday Beer, and I hear that at UCLA it's known as Liquidus. On Twitter, Iconfirmed that earth scientists at CalTech, The Borehole Research Group and the University of Sao Paulo in Brazil also have a weekly beer congregation.

"I've been to a few geo departments around the world, and most of them have Friday Beer," said Stanford biogeochemist Sharmini Pitter.

"We have three weekly beer gatherings," saidChristopher Harrisonof the University of Miami.

None of the theories can be ruled out by this preliminary study, and neither can the possibility that all three are correct.Certainly, more research is needed. But one thing is clear: The love affair between geoscientists and beer is one for the eons.

Video: Michael Lennon/

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