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El Portal, CA, United States

News Article
Site: http://phys.org/biology-news/

The range for the mountain-dwelling herbivore is decreasing in southern Utah, northeastern California and in the Great Basin that covers most of Nevada and parts of Utah, Oregon, Idaho and California, the federal agency concluded after studying the cuddly looking critter from 2012-2015. This study's conclusion marks a more authoritative statement about the role of global warming on the animal compared to research released in 2003 that found climate change was at least partly contributing to the animal's decline. "The longer we go along, the evidence continues to suggest that climate is the single strongest factor," said Erik Beever, a research ecologist with the U.S. Geological Survey and lead author. The pika's habitat on mountain slopes, known as talus, are hotter and drier in the summer and more harsh in the winter with less snowpack to serve as an insulator, Beever said. The study bolsters the case for wildlife advocacy groups pushing for years to have the animal added to the endangered species list amid concerns about global warming. The U.S. Fish and Wildlife Service rejected a request in 2010, saying not all populations were declining. A new request was made this April by a high school student in New York state. A preliminary decision on that request is due out in early September, but the agency's staff won't take into account the new study because they are bound to only take into account information submitted with the petition, said Fish and Wildlife Service spokeswoman Serena Baker. Noah Greenwald, the Center for Biological Diversity's endangered species director, said the new research confirms that climate change is putting the animal at real risk. He said it should help with future petitions to have the animal declared endangered—something he says is necessary to ensure future generations are treated to seeing the critters during mountain hikes. "It's gotta be one of the cutest animals in North America. It's like a cross between a bunny rabbit and prairie dog," Greenwald said. "Part of what makes our world interesting is the diversity of animals and plants that you can see when you go to different species." President Barack Obama mentioned the plight of the pika this summer when he spoke at Yosemite National Park about the damage climate change is inflicting on the nation's national parks. He said the pika was being forced further upslope at Yosemite to escape the heat. The study didn't quantify how many total American pika still exist, but honed in on several areas where the small animal has historically roamed eating grass, weeds and wildflowers. The animal is thriving in a few places, such as the Columbia River Gorge in Oregon and Grand Teton National Park in Wyoming, but overall is suffering, Beever said. At Utah's Zion National Park, they're gone all together despite being seen as recently as 2011. In nearby Cedar Breaks National Monument, they're no longer in three-fourths of their historical habitat, Beever said. Pikas were only found in 11 of 29 sites where they once lived in northeastern California. In the Great Basin, which stretches from Utah's Wasatch Mountains in the east to the Sierra Nevada and Cascade Mountains in the west, the population is down about 44 percent compared to historical records. "It's not that they've just moved, they are gone all together," Beever said. Explore further: Pikas in peril in the Rockies


News Article
Site: http://www.sej.org/headlines/list

"After a year of hype and hope, El Niño's punch is finally arriving in California, bringing a series of storms to soak the Bay Area and most of the rest of the drought-stricken state through this week and probably into next. The National Weather Service is forecasting the wettest week of this winter so far -- rain in six of the next seven days, with the heaviest downpours expected Tuesday and Wednesday in the Bay Area, bringing potential rain totals of up to 5 inches in higher elevations. Forecasters expect 1 to 3 inches in most Bay Area cities. A flash flood watch is in effect through Tuesday morning for the Big Sur coast, and a winter storm warning is underway through Tuesday night for the southern Sierra Nevada, from Yosemite National Park to Kern County, where 2 feet or more of snow is expected in the next few days." "El Niño effect: California Preps For Two Weeks Of Rain And Snow " (AP)


News Article
Site: http://www.nature.com/nature/current_issue/

Rockfalls in steep terrain could be triggered by warm weather. Precipitation, earthquakes and freeze–thaw cycles are known to increase the risk of rockfalls, but some falls have no known cause. Brian Collins of the US Geological Survey in Menlo Park, California, and Greg Stock of the US National Park Service in El Portal, California, attached 'crackmeters' to a 500-metre cliff in California's Yosemite National Park. They found that a crack behind a slab in the cliff widened every day as the rock expanded in the heat, and closed up at night. It was also wider during the summer than in the winter. Over 3.5 years, the crack steadily opened up, and the authors say that such rock slabs could eventually fall, even without stresses such as an earthquake or heavy rain. The study suggests that warm summer afternoons are most likely to see such rockfalls, which matches records at Yosemite and other places around the world.


News Article | March 29, 2016
Site: http://www.techtimes.com/rss/sections/environment.xml

Scientists believe that climate change may be the culprit behind the mysterious rockfalls in Yosemite. The occurrence of spontaneous rockfalls often does not have a specific cause. From time to time, slabs of rocks can suddenly fall down. However, scientists did a close monitoring of a granitic cliff and noted that cyclical changes in temperature causes the hard rocks to accumulate damage until the rocks crack. In the Yosemite National Park in California, rockfalls seems to be ordinary with about hundreds occurring periodically. About 15 percent of these rockfalls do not have any trigger, such as earthquakes or freeze-thaw cycles that can trap water in a fissure that can in turn cause a crack. The Brian Collins, a geological engineer from the U.S. Geological Survey (USGS) and a mountain climber, worked with Yosemite National geologist Greg Stock to identify the cause of the frequent rockfalls. The experts installed strain gauges and crackmeters to measure the overall length changes at three spots present in a 19-meter (62-feet) long and 4-meter (13-feet) long slab. The slab has its top and bottom edges barely attached to a south facing cliff. From May 2010 to October 2013, the scientists identified and measured, every 5 minutes, the deformations present in the near vertical 20 metric ton (293.49 cubic feet) layer of granite slab, which is about 10 centimeters (0.3 inch) thick. The scientists also monitored the slab movements along the directions it was splitting. Weather conditions including sunlight intensity and air conditions on site were also taken into consideration, even getting the air temperature and humidity from the slab surface and slab gaps that are only about 4.7 inches wide. To gain an independent measurement of the rock motions in an 18-hour period, the experts scanned the slabs from 30 meters away (98 feet) using a laser device. The study found that in an average day, the slab would have periodic bulging and shrinking of about 8 millimeters (0.31 inch), which is largely due to the temperature variations. During the highest temperature of the day, between 1 p.m. and 4 p.m., the maximum bulges were noted. On the other hand, minimum bulges occurred in the morning (7 a.m. to 9 a.m.) where temperature is at its lowest. The range of deformations was also noted to be greatly affected by temperature changes as biggest deformations would occur during spring and fall. Collins said the material expands as the material heats up but because it has edges that are still attached to a rock, the slab would only bulge and shrink. The periodic bulging causes cracks and fissure at the top and bottom of the slab to open. These open cracks generate stresses, grow and eventually cause rockfalls. "Over time, the cracks are going to become bigger and bigger and bigger and ultimately result in a rockfall," Collins said. He added that intensifying changes in temperature brought about by climate change may aggravate the process. Collins and Stock reported that about 15 percent of the national park's rockfalls, which may be linked to thermal stresses, happen during the warmest time of the day (from noon time to 6 p.m.) and during the hottest months (July to September) of the year. The scientists surmised that if the event happened at random, the number of rockfalls at those times would only amount to about 6 percent. Geologists believe the study is an eye opener that offers new information about rocky landscapes. Jeffrey Moore, a University of Utah geologist, said daily temperature variation can also cause similar stress in layered sandstones that could also lead to cracking and trigger rockfalls. Stephen Martel, a geologist from the University of Hawaii, also said thermal stresses, previously ignored, gave them a different perspective. He noted that studies about these phenomena are important as they could help in disaster management. The scientists of the new study said their research cannot help in rockfall predication, but it does give an understanding of how such events can occur. The study does not only offer hazard assessment for Yosemite alone, but also in other rock formations around the world, as climate change persists. Due to Yosemite's steep, glacier-carved cliffs, rockfalls are quite common. In the past 150 years, the park had about 1,000 rockfalls. In 2015 alone, the park had 66 documented rockfalls that had about 8,700 cubic meters of rocks. Yosemite National Park is a favorite among rock climbers. In 2014, two rock climbers braved the Dawn Wall of the El Capitan mountain, which is 3,000 feet above the park using only their bare hands and feet. The El Capitan mountain was previously tagged as the greatest cliff for rock climbing.


News Article | April 28, 2016
Site: http://motherboard.vice.com/

As someone with the metabolism of a racehorse on methamphetamine, I’m blessed with the need to pee all the damn time. Luckily, I’ve never been too late, but I do generally plan my outdoor activities around the nearest public restroom. One time, I was at Yosemite National Park, admiring a beautiful waterfall, when the rhythmic downpour of rushing water made me dash off in search of the nearest outhouse. The urge to pee in the presence of running water isn’t weird. Most people are probably familiar with this sensation, so there must be some scientific basis for the phenomenon. Thankfully, the folks over at SciShow have trickled a little bit of light on the connection in their latest video. The hypothetical answer, according to psychologists and urologists, has everything to do with a principle you learned about in high-school biology: classical conditioning, or the experiment demonstrated by Russian psychologist Ivan Pavlov and his dogs. Classical conditioning is a learning theory that relies on automatic response mechanisms to explain why animals (including us) react to certain things seemingly subconsciously. So, as the most famous example goes, Pavlov’s dogs naturally salivated around food. Knowing this, the psychologist rang a bell every time he gave his dogs their daily meals. Over time, the dogs learned to associate the sound of a bell ringing with meal-time. And, eventually, the clang of the bell without the presentation of food was enough to make them drool. All of this is controlled by a neural network called the autonomic nervous system. Likewise, when it comes to running water and peeing, the theory is that we’ve simply been conditioned to play out a specific response to a particular stimulus. Peeing sounds like tinkling water, ergo a leaky faucet reminds us that we need to go. Some reflexes can be hard-wired, such as catching yourself when you fall, but others can be learned through repetition. Surprisingly, there’s relatively little scientific research on the role that classical conditioning plays in this peepee phenomenon. But parents trying to potty train their toddlers and patients suffering from “shy bladder syndrome” are often encouraged to let the sink run to get things going. According to SciShow, even a photograph of falling water can be enough to elicit a steady stream. If the Pavlovian argument is true, you could theoretically also desensitize your mind the sound of water. Using cognitive behavioral therapy, a person could counter-condition themselves to replace an unwanted response (peeing) with an acceptable one. This training technique is often used to curb bad behavior in dogs, although it’s never worked on my own hound. So if you’re really worried about a babbling brook setting you off, you might have some options. Otherwise, maybe just go before leaving your house?

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