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Arctic Could Be Ice-Free in 2008
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On average each year in the Arctic about half of the first year ice, formed between September and March, melts during the following summer.
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You know when climate change is biting hard when instead of a vast expanse of snow the North Pole is a vast expanse of water. This year, for the first time, Arctic scientists are preparing for that possibility.
“The set-up for this summer is disturbing,“ says Mark Serreze, of the US National Snow and Ice Data Center (NSIDC). A number of factors have this year led to most of the Arctic ice being thin and vulnerable as it enters its summer melting season, NewScientist reported.
In September 2007, Arctic sea ice reached a record low, opening up the fabled North-West passage that runs from Greenland to Alaska. The ice expanded again over the winter and in March 2008 covered a greater area than it had in March 2007. Although this was billed as good news in many media sources, the trend since 1978 is on the decline.
Arctic ice at its maximum in March, but that maximum is declining by 44,000 km2 per year on average, the NSIDC has calculated. That corresponds to an area roughly twice the size of New Jersey. What is more, the extent of the ice is only half the picture. Satellite images show that most of the Arctic ice at the moment is thin, young ice that has only been around since last autumn. Thin ice is far more vulnerable than thick ice that has piled up over several years.
“There is this thin first-year ice even at the North Pole at the moment,“ says Serreze. “This raises the specter--the possibility that you could become ice free at the North Pole this year.“ Despite its news value in the media, the North Pole being ice free is not in itself significant. To scientists, Serreze points out, “this is just another point on the globe“. What is worrying, though, is the fact that multi-year ice--the stuff that doesn’t melt in the summer--is not piling up as fast as Arctic ice generally is melting.
On average each year about half of the first year ice, formed between September and March, melts during the following summer. In 2007, nearly all of it disappeared. Moreover, an atmospheric phenomenon known as the Arctic oscillation kicked into its strong, ’positive’, phase this winter. This is known to generate winds which push multi-year ice out of the Arctic along the east coast of Greenland.
Together, these are the factors that have led to most of the Arctic ice now being so young and thin. “Even if you lost only half of the first-year ice this year--which would be average--you are still in for a very low ice extent this summer,“ says Serreze.
Some factors could still save the day, though. In summer 2007, warm winds favored melting. “If we have an atmospheric pattern like we had last year, we are going to lose a whole bunch of ice this summer, but if we have a cooler, more cyclonic pattern, that might preserve some of that ice,“ says Serreze.
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Brains Hard-Wired to Hate Losing
Competitive types who get a buzz from climbing the social ladder also feel more pain when they plummet to a lesser rung. That’s according to new research suggesting our brains are hard-wired for hierarchy.
Researchers from the National Institute of Mental Health (NIMH) set up an artificial social hierarchy, or ranking, in which 72 participants were assigned a status representing their supposed skills at a computer game.
Then, participants saw pictures and scores of an inferior and a superior player, LiveScience reported.
Brain scans showed that when a superior player’s image popped up, participants’ brains were activated in areas thought to guide interpersonal judgments and social status--basically, sizing up others.
When a participant outperformed a superior “other player,“ brain regions responsible for action planning were activated. Brain regions linked to emotional pain and frustration showed activity in participants when they performed worse than a supposed inferior player.
Participants also answered questionnaires throughout the game.
Turns out, the ’high’ that a person feels at the top of the hierarchy can turn into a major downer at the bottom.
Individuals who reported more elation while at the top also showed increased activity in the brains emotional-pain circuitry when they performed worse than another player, threatening their status.
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Food Dyes May Protect Against Cancer
Synthetic food dyes--long blamed for causing hyperactivity in children--may have a good side: some of them may protect against cancer.
Gayle Orner at Oregon State University in Corvallis added the carcinogens dibenzopyrene (DBP) or aflatoxin to the feed of trout for one month, with or without the food dyes Red 40--one of six recently linked to hyperactivity in children--or Blue 2, NewScientist reported.
Nine months later, trout that had been fed either of the dyes in combination with aflatoxin had 50 percent fewer liver tumors, compared with those that had been exposed to aflatoxin alone. Trout that had been fed DBP in combination with Red 40 had a 50 per cent lower incidence of stomach cancer and a 40 percent lower incidence of liver cancer.
“The public perception is that food dyes are bad, but some of them may have good points as well,“ says Orner, who presented her results at the American Association for Cancer Research in San Diego, California, last week.
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Thinking & Appetite
Perhaps it really is possible to think yourself slimmer. Concentrating on a recent meal turns out to significantly reduce the desire to snack,
suggesting that certain ways of thinking can curb your appetite.
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Papaya Genome Bares Evolution’s Secrets
Papayas have extra copies of genes that make them sweet and nutritious, researchers said in a study that can help shed light on how flowering plants evolved. They published the complete genetic sequence of the “SunUp“ papaya, a tree genetically engineered to be virus resistant, Reuters said.
Writing in the journal Nature, they said the plant has fewer genes than the more thoroughly studied weed Arabdopsis, yet has a longer DNA sequence.
They believe they have pinpointed genes responsible for helping tree-like plants evolve, and genes that helped make it smell and taste so good, attracting animals and people to spread its seeds. Papayas have extra genes that appear to code for these aromas and for storing starch, presumably in the fruit.
“This also foreshadows what we might expect to discover in the genomes of other fragrant-fruited trees, as well as plants with striking fragrance of leaves (herbs), flowers or other organs,“ Maqsudul Alam of the University of Hawaii and colleagues wrote.
Lazy Lizards Run, Don’t Walk
Like humans, some lizards are always on the go, grabbing food en route, while others wait like couch potatoes expecting pizza delivery.
New video research finds the lazy lizards that wait for food to pass by on a seeming silver platter actually have evolved into skilled sprinters, while the constantly active foragers are built for long walks, LiveScience said.
Monitor lizards and some skinks are considered wide foragers. They spend 80 percent of their lives on the move, slowly slinking about using their specialized tongues to chemically sniff out prey.
The sit-and-wait lizards, well, sit and wait. Then when a meal passes by, the iguana, for instance, lunges like a hungry delivery customer hearing the doorbell, to sprint after the unsuspecting morsel and snatch it up with a tongue flick.
To figure this out, using high-speed video and force measurements, researchers tracked 18 lizard species as they trekked along a racetrack at a range of speeds. The wide foragers used a walking gait, which the scientists say allows them to sniff every little nook in search of food. The “pizza predators“ always ran, even when moving at relatively slow speeds.
Bugs Use Plants as Telephones
“Hello? Yes, this is my plant. Thanks. Bye-bye.“
That’s the underground half of a conversation between bugs on a mustard plant. Scientists have discovered the insects below and above use the plant like a chemical telephone, LiveScience wrote.
A team of researchers led by Roxina Soler, an ecologist at the Netherlands Institute for Ecology, are not sure how widespread the phenomenon is.
The organic chat is a friendly one: Leaf-munching insects above ground prefer plants unoccupied by root-eaters.
When a subterranean insect takes up residence below a plant, it settles in to feast on the plants; roots. In order to alert leaf-eating insects of the “no vacancy,“ the underground insect sends a chemical warning signal through the plant leaves, so the leaf eaters are alerted that the plant is occupied.
Balding Penguin Given Wetsuit
A penguin in a wetsuit, naturally. Sounds like a joke, but it’s quite serious for biologists at the California Academy of Sciences, who had a wetsuit created for an African penguin to help him get back in the swim of things.
Pierre, a venerable 25 years old, was going bald, which left him with an embarrassingly exposed, pale pink behind, AP said. Unlike marine mammals, which have a layer of blubber to keep them warm, penguins rely on their waterproof feathers. Without them, Pierre was unwilling to plunge into the academy’s penguin tank and ended up shivering on the sidelines while his 19 peers played in the water.
“He was cold; he would shake,“ said Pam Schaller, a senior aquatic biologist at the academy. Schaller first tried a heat lamp to keep Pierre warm. Then she got another idea: If wetsuits help humans frolic in the chilly Pacific, why not whip up one in a slightly smaller size?
Staff at Oceanic Worldwide, a supplier of dive gear based in San Leandro, were enthusiastic about making a real penguin suit.
Schaller conducted fittings to design the suit, which fastens with Velcro at the back, covers Pierre’s torso and has small openings for his flippers.
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