In case there aren't any legal folk with me in their circles, please ask around for me and let me know. Just curious.
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Thursday, the ESA's Rosetta probe returned images from the comet it orbits during its closest approach to the Sun, or perihelion. At perihelion, Comet 67P/Churyumov–Gerasimenko is about 186 million kilometers from the Sun, or a bit outside of Earth's orbit (150 million kilometers).
With the added warming from the Sun, the comet has been experiencing higher levels of activity, with gasses escaping from its interior at higher levels, pushing dust and other material out into space. Rosetta's instruments indicate about 300 liters of water are being ejected every second, meaning the comet is losing 26 million kilograms per day during this period. Another 86 million kilograms of dust are also being lost. The activity should remain high for several weeks after perihelion.
Because of the large volumes of material jetting out of the comet, the ESA's operators have backed Rosetta off to an orbit that's over 325km from the comet's surface. But that's still close enough for some pretty spectacular images.
Since 2010, the best estimate of the age of Earth’s magnetic field has been 3.45 billion years. But now
The post Researchers find that Earth’s magnetic shield is 500 million years older than previously thought has been published on Technology Org.
Ten years after launch, NASA’s Mars Reconnaissance Orbiter (MRO) has revealed the Red Planet’s diversity and activity, returning
The post One Decade after Launch, Mars Orbiter Still Going Strong has been published on Technology Org.
EARLIER THIS WINTER, Monica Zappa packed up her crew of Alaskan sled dogs and headed south, in search of snow. "We haven't been able to train where we live for two months," she told me.
Alaska's Kenai Peninsula, which Zappa calls home, was practically tropical this winter. Rick Thoman, a meteorologist with the National Weather Service in Alaska, has been dumbfounded. "Homer, Alaska, keeps setting record after record, and I keep looking at the data like, Has the temperature sensor gone out or something?"
Something does seem to be going on in Alaska. Last fall, a skipjack tuna, which is more likely to be found in the Galápagos than near a glacier, was caught about 150 miles southeast of Anchorage, not far from the Kenai. A few weeks ago, race organizers had to truck in snow to the ceremonial Iditarod start line in Anchorage.
Alaska is heating up at twice the rate of the rest of the country — a canary in our climate coal mine. A new report shows that warming in Alaska, along with the rest of the Arctic, is accelerating as the loss of snow and ice cover begins to set off a feedback loop of further warming. Warming in wintertime has been the most dramatic — more than 6 degrees in the past 50 years. And this is just a fraction of the warming that's expected to come over just the next few decades.
Of course, it's not just Alaska. This February was the most extreme on record in the Lower 48, and it marked the first time that two large sections of territory (each more than 30 percent of the country) experienced both exceptional cold and exceptional warmth in the same month, according to data from the National Oceanic and Atmospheric Administration. All-time records were set for the coldest month in dozens of Eastern cities, with Boston racking up more snow than the peaks of California's Sierra Nevada. A single January storm in Boston produced more snow than Anchorage saw all winter.
ALASKA IS ON the front lines of climate change. This year's Iditarod was rerouted — twice — because of the warm weather. The race traditionally starts in Anchorage, which had near-record-low snowfall this winter. The city was without a single significant snowstorm between October and late January, so race organizers decided to move the start from the Anchorage area 360 miles north to Fairbanks. But when the Chena River, which was supposed to be part of the new route's first few miles, failed to sufficiently freeze, the starting point had to move again, to another location in Fairbanks.
On March 9, Zappa set out with her dogs on the 1,000-mile race across Alaska as one of 78 mushers in this year's Iditarod. For most of the winter, the weather across the interior of the state had been abnormally warm. To train, many teams of dogs and their owners had to travel, often "outside" — away from Alaska. Zappa ended up going to the mountains of Wyoming.
A recent study said that Alaska's rivers and melting glaciers are now outputting more water than the Mississippi River. Last year was Alaska's warmest on record, and the warm weather has continued right on into 2015. This winter, Anchorage essentially transformed into a less sunny version of Seattle. As of March 9, the city had received less than one-third of its normal amount of snow. In its place? Rain. Lots of rain. In fact, schools in the Anchorage area are now more likely to cancel school because of rain and street flooding than because of cold and snow.
Of course, it wasn't always this way. Alaska's recent surge of back-to-back warm winters comes after a record-snowy 2012, when the National Guard was employed to help dig out buried towns. Then, about two years ago, something in the climate system switched. The state's recent brush with extreme weather is more than just year-to-year weather variability. Alaska is at the point where the long-term trend of warming has begun to trump seasonal weather fluctuations. A recent shift toward warmer offshore ocean temperatures is essentially adding more fuel to the fire, moving the state toward profound tipping points like the irreversible loss of permafrost and increasingly violent weather. If the current warm ocean phase (which began in 2014) holds for a decade or so, as is typical, Alaska will quickly become a different place.
The Pacific Ocean near Alaska has been record-warm for months now. This year is off to a record-wet start in Juneau. Kodiak experienced its warmest winter on record. A sudden burst of ocean warmth has affected statewide weather before, but this time feels different, residents say. In late February, National Weather Service employees spotted thundersnow in Nome — a city just 100 miles south of the Arctic Circle. "As far as I know, that's unprecedented," Thoman told me. Thunderstorms of any kind require a level of atmospheric energy that's rarely present in cold climates. To get that outside of the summer is incredibly rare everywhere, let alone in Alaska.
Climate scientists are starting to link the combination of melting sea ice and warm ocean temperatures to shifts in the jet stream. For the past few winters, those shifts have brought surges of tropical moisture toward southern Alaska via potent atmospheric rivers. This weather pattern has endured so long, it's even earned its own name: the Ridiculously Resilient Ridge. The persistent area of high pressure stretching from Alaska to California has shunted wintertime warmth and moisture northward into the Arctic while the eastern half of the continent is plunged into a deep freeze, polar-vortex style.
The warm water is making its way north into the Arctic Ocean, too, where as of early March, sea ice levels were at their record lowest for the date. The resurgent heating of the Pacific (we're officially in an El Niño year now) is also expected to give a boost to global warming over the next few years by releasing years of pent-up oceanic energy into the atmosphere, pushing even more warm water toward the north, melting Alaska from all sides.
That means Alaska's weather, according to one Alaska meteorologist, is "broken." Dave Snider, who reports statewide weather daily for the National Weather Service's Alaska office in Anchorage, tweeted the sentiment back in mid-January. Snider emphasized that this isn't the official view of the National Weather Service, "of course." Snider told me he made the comment "sort of in jest" but pointed to the nearly snow-free Iditarod start as evidence.
Here's another example he could have used: In early November, Super Typhoon Nuri morphed into a huge post-tropical cyclone, passing through the Aleutians very near Shemya Island on its way to becoming Alaska's strongest storm on record. Despite winds near 100 mph, Shemya emerged relatively unscathed. A few days later, the remnants of that storm actually altered the jet stream over much of the continent, ushering in a highly amplified "omega block" pattern that dramatically boosted temperatures across the state and sent wave after wave of Arctic cold toward the East Coast. Barrow was briefly warmer than Dallas or Atlanta.
THE WARM WEATHER isn't all bad news. The city of Anchorage has saved an estimated \$1 million on snow removal this year and is instead pouring the money into fixing potholes and other backlogged maintenance issues. But getting around the rest of the state hasn't been so easy.
There are few roads in rural Alaska, so winter travel is often done by snowmobiles over frozen rivers. Not this year. Warm temperatures in February led to thin ice and open water in the southwest part of the state near Galena and Bethel. David Hulen, managing editor for the Alaska Dispatch News in Anchorage, has spent nearly 30 years in the state. He says the freeze-thaw cycle is out of whack, "changing the nature of the place." Usually, things freeze in the fall and unfreeze in the spring; this winter, they've seen a nearly constant back and forth between freezing and thawing.
That's made it difficult for skiers and those enjoying other outdoor activities, like riding fat-tire bikes attuned to the snow. Julie Saddoris, of the Bike Me Anchorage Meetup, says attendance in her group was down this winter. Hulen agrees that it's been frustrating. "I mean, what's living in Alaska if it's not cold and snowy?"
Those are city problems. Along the state's west coast, some native coastal villages are facing an existential threat, as sea levels rise in response to the warm water. Earlier this winter, Washington Post climate reporter Chris Mooney visited Kivalina, one of the six villages considering plans to relocate because of climate change. "Here, climate change is less a future threat and more a daily force, felt in drastic changes to weather, loss of traditional means of sustenance like whale hunting, and the literal vanishing of land," Mooney wrote. Another village, Newtok, is a bit further along in the relocation process, with construction on their new village — Mertarvik — already underway.
For now, the most visible change is still in the shifting habitats of the fish, birds, trees, and animals. Permafrost still covers 85 percent of the state, but "almost everywhere, the depth of the active layer is increasing over the last few decades," said Thoman. Since the active layer — the zone of soil above the permafrost that thaws out each summer — now penetrates deeper down, that means landforms are shifting, lakes are draining, and new forests are springing up.
Patricia Owen is a biologist at Denali National Park and Preserve who studies grizzly bears. Last winter, warm weather brought blueberry blossoms earlier than normal. The blossoms then froze, making foraging for food more challenging for bears. Mother bears need to have good health in the fall to support their cubs during the long winter months of hibernation. Owen is seeing evidence of other changes within Denali: More episodes of freezing rain are having a big impact on sheep, which have to scrape through ice to eat. In low-snow years like this one, wolves seem to suffer, since caribou and moose can escape more quickly.
Recent warming also appears to have pushed Denali's poplar forests across a threshold toward rapid expansion. Carl Roland, a Denali plant ecologist who has compiled a trove of repeat photographs around the park spanning decades of environmental change, says that what he's seeing is "dramatic."
Once the permafrost goes, Roland says, we can expect a "regime shift" in the park and across the state. The northward spread of tree-killing insects is also a "really big unknown" in interior Alaska. Last spring, a huge forest fire in a beetle kill area of the Kenai Peninsula sent smoke plumes hundreds of miles northward toward Fairbanks.
For southern Alaska, fire season has been coming earlier in recent years, and 2015 looks to be no exception. A few years ago, the Alaska Division of Forestry statutorily moved the start of the fire season up from May 1 to April 1 "as a result of climate change," Tim Mowry, a division spokesman, told me. The change, Mowry says, was intended to elicit "a sense of urgency."
Excerpted from an article that originally appeared on Slate.com. Reprinted with permission.
The octopus is one of Earth's most striking creatures, able to exert fine control over a complex and flexible body all while constantly adjusting its coloration through specialized organs on its skin. The creatures also appear to be rather smart; researchers have found evidence of complex problem solving and observational learning. All of this from an animal that is part of the mollusks, a group we often associate with things like clams.
Of course, mollusks started diversifying back when the only vertebrates were fishes, so that's plenty of time for them to evolve some distinctive features. To get a better glimpse of what, exactly, evolved, researchers have now sequenced the genome of the California two-spot octopus. The answer to the octopus' surprising smarts seems to be the expansion of two types of genes, along with the generation of hundreds of new ones.
Sequencing the genome wasn't an easy task. Unlike some invertebrates like Drosophila, the octopus' genome is roughly the same size as many mammals (2.7 billion bases long, about 90 percent the size of the human genome). But a team of researchers has managed to get 83 percent of those bases, covering almost all of the organism's 33,700 genes. According to author Daniel Rokhsar, the California two-spot octopus (Octopus bimaculoides) was chosen simply because it's easy to work with in a lab.
Today's CometWatch entry is an image of Comet 67P/Churyumov-Gerasimenko taken on 6 August 2015, exactly a year to
In the last two decades, prosthetic limb technology has grown by leaps and bounds. Today, the most advanced
The earliest example of multicolor printing is now available for the public eye, digitally available through Cambridge University Library’s Digital Library site. The 17th century book, Manual of Calligraphy and Painting (Shi zhu zhai shu hua pu), is so fragile that it was previously forbidden to be opened, its contents a total mystery before its recent digitization.
The book was created in 1633 by Ten Bamboo Studio and is the earliest known example of polychrome xylography, invented by Hu Zhengyan. The technique, also referred to as douban, uses several printing blocks applied in succession with different inks to achieve the appearance of a hand-painted watercolor. The Cambridge site explains that the although the skill required to achieve such douban prints is admirable, the gradations of color within the book are what led to its reputation as “perhaps the most beautiful set of prints ever made.”
The manual contains eight categories showcasing birds, plumbs, orchids, bamboos, fruit, stones, ink drawings and miscellany. All of these sections of the manual are contained in the original “butterfly binding,” and has been identified to be the finest copy in the original binding by a leading scholar.
In addition to Shi zhu zhai shu hua pu, the library has also digitized other selections from its Chinese collections including the oracle bones (the earliest surviving examples of Chinese writing anywhere in the world), a Buddhist text dated between 1127 and 1175, and a 14th century banknote that threatens forgers with decapitation. (via Hyperallergic)