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Updated: 1 hour 14 min ago

Climate change could lengthen North American winters

1 November 2016

Washington Post: One of the most notable effects of rising global temperatures has been the loss of Arctic ice. A new study suggests that ice loss is causing the polar vortex to shift, which could lead to longer winters in North America. Over the past three decades of warming, the vortex has weakened and moved toward Europe and Asia during February. A weakening vortex is more likely to fracture and allow extremely cold air to flow south from the Arctic, as happened several times over the past two winters. The vortex's shift in position during mid to late winter means that the fractures are more likely to continue into early spring, the researchers say, and pour cold Arctic air across North America.

Oil drilling may have induced earthquakes in California a century ago

1 November 2016
NPR: Although Southern California has long been known as a natural earthquake hazard, some of the biggest quakes that occurred in the early 20th century may actually have been caused by oil and gas production, according to a new study published in the Bulletin of the Seismological Society of America. To study quakes that occurred during the California oil boom of the 1920s and 1930s, before the advent of modern seismological data collection methods, Susan Hough and Morgan Page of the US Geological Survey used old scientific surveys, instrument data, and newspaper articles. The researchers were able to link several damaging earthquakes during the period 1915–32 with drilling operations around Los Angeles. However, the researchers say their findings are of historical importance only, because the industry practices in use at the time are no longer employed.

Finding the magma source for Mount St Helens

1 November 2016
Seismic imaging reveals a cold mantle beneath the volcano and suggests that magma migrates from the east.

NSF may close Green Bank Observatory

1 November 2016

Charleston Gazette–Mail: The Green Bank Observatory in West Virginia is home to the world's largest fully steerable radio telescope as well as three smaller radio telescopes and a radio burst spectrometer. However, Green Bank was recently dropped from the National Radio Astronomy system, and NSF has cut its funding. On 19 October, NSF filed notice that it is evaluating what to do with the facility. The possibilities include continuing operation of the observatory with mixed NSF and secondary funding, continuing operation with NSF funding only, converting the site into a technology and education park, mothballing the facility for potential future use, or dismantling it.

Manfred A. Biondi

1 November 2016

The persistence of ash in the stratosphere

31 October 2016
A new study refutes the assumption that sulfate aerosols are the only volcanic material that shades Earth’s surface.

NASA finds near-Earth object during test of new detection system

31 October 2016

NPR: For several years NASA has been operating an asteroid tracking system called Sentry, which is identifying and tracking all near-Earth objects (NEOs) in the solar system that pass through Earth's orbit and are large enough to wipe out a major city. Now the agency is testing a similar system called Scout, which is designed to identify and track NEOs smaller than the 140 m diameter that is Sentry's threshold. NASA has contracts with multiple telescopes around the globe to scan the skies for such objects. When one is detected, Scout makes a rough calculation of the object's apparent path. If there is a chance of impact with Earth, the system calls for other telescopes to make follow-up observations. On 25 October the Panoramic Survey Telescope & Rapid Response System in Hawaii spotted an NEO, which Scout determined would pass Earth at a distance of around 500 000 km. Subsequent observations confirmed the calculation and allowed for an estimate of the diameter. On 30 October the small asteroid passed Earth without incident.

Postdoc numbers rebound at national centers

28 October 2016
More than a quarter of the nearly 2700 postdoctoral researchers focus on physics and astronomy.

Satellites: Invaluable eyes in the sky

28 October 2016
Space-based sensors, which acquire measurements of the atmosphere above even the most remote places on Earth, are used to improve weather and climate models.

Neutron holography makes its debut

27 October 2016
The technique could be useful for imaging the interiors of bulk objects.

Multiple earthquakes strike central Italy

27 October 2016

BBC: On 26 October two earthquakes, one magnitude 5.5 and the other magnitude 6.1, struck two hours apart near the town of Visso, Italy. In August a magnitude 6.2 earthquake killed nearly 300 people in Amatrice, just 70 km away. Damage and injury reports from yesterday's quakes suggest that the damage was not as severe. The first quake occurred at a relatively shallow depth of 9 km, with an epicenter 7 km southwest of Visso. The second quake struck 2 km north of the town at a depth of 10 km. Mario Tozzi of Italy's National Institute of Geophysics says it's likely the two earthquakes were aftershocks of the August quake.

Imagining humans on Mars

27 October 2016
Billionaire Elon Musk hopes to build self-sustaining human colonies on Mars. How have science fiction writers imagined the possible role of Mars in humanity’s future?

US fourth and eighth graders show improvement in science

27 October 2016
Washington Post: The 2015 US National Assessment of Educational Progress indicates that fourth- and eighth-grade students scored four points higher in science than did their counterparts in 2009. High school seniors, however, performed about the same as those in 2009. The Nation’s Report Card, as the assessment is sometimes called, has been administered for decades, with exams given every two years in math and reading and less often in science and other subjects. Because the science test was substantially revised in 2009, however, current test results can’t be compared with those from pre-2009 years. Although the data show positive improvements in student performance, there are no data to show why the students did better.

New, fast computer uses fiber optics and light pulses

26 October 2016
Ars Technica: Two teams of researchers have developed Ising machines that use light pulses that travel through a fiber-optic racetrack to make computations. Traditional Ising models solve algorithms by using tiny magnets that can be individually tuned to align a particular way relative to every other magnet. The new system relies instead on artificially coupling light pulses via their phases and amplitudes. A light-based computer can be much more easily scaled up in size. The researchers have already demonstrated that their systems can handle some 2048 bits. An Ising machine works differently from a classical computer in that it provides a good, but not necessarily the best, solution to a given problem. However, an Ising machine is much speedier—in this case, 10 times as fast as a classical computer given the same problem.

Metamaterial shrinks rather than expands when heated

26 October 2016
New Scientist: Most materials expand when exposed to heat. That expansion can cause structures such as bridges, microchips, and satellites to deform. Now Qiming Wang of the University of Southern California and his colleagues have developed a metamaterial that shrinks when heated. In the loose 3D-printed matrix, the material that expands slower encases the faster-expanding one. When heated, the trapped inner material can only expand inward, and as it does it pulls the outer material with it. Depending on which materials are used, the entire structure can be designed to expand or shrink at a desired rate. Such a metamaterial could have many uses, such as in dental fillings. Current fillings can lead to sensitivity because they react differently from the surrounding tooth when exposed to hot and cold substances.

Iridescence in shade-dwelling plant species linked with photosynthesis

25 October 2016
Popular Mechanics: Certain plant species, such as the Malaysian tropical Begonia pavonina, are unusual because of the iridescent blue of their leaves. Heather Whitney of the UK’s University of Bristol and her colleagues recently investigated why the leaves are blue. Using an electron microscope, the researchers were able to study the cellular structure of the plant’s leaves; they found that unlike most plants, the Begonia’s chloroplasts have a very rigid, precise arrangement. The ordered structure not only acts like a dense crystal that favors red–green light and reflects blue light, but it also causes light to slow down as it passes through. As a result the Begonia plant, which dwells in shadowy conditions on the rainforest floor, is 10% more efficient at photosynthesis than it otherwise would be, the researchers say. Furthermore, the plant also contains some normal chloroplasts. The mix of the normal and highly ordered chloroplasts may allow the plants to adjust between normal light levels and extremely low levels.

Climate change prompts US government to protect potentially endangered seal species

25 October 2016
Los Angeles Times: A recent decision by the US 9th Circuit Court of Appeals to list a Pacific bearded seal subspecies as threatened has been challenged by the state of Alaska and the oil and gas industry. The decision was based on climate modeling projections that show that the ice floes where the seals breed and raise their young could disappear by the end of the century because of global warming. The challengers counter that the seal population is currently healthy, climate projections are speculative, and the ruling could interfere with offshore drilling efforts. Judge Richard Paez wrote for the court, however, that the government “need not wait until a species’ habitat is destroyed to determine that habitat loss may facilitate extinction.” The court’s decision could have major implications for other climate-threatened species.

Obama science legacy draws media attention

25 October 2016
One recurring theme is the president’s optimistic belief that humans “can science the heck out of just about any problem.”

Climate scientist dies in snowmobile accident in Antarctica

24 October 2016
New York Times: Climate scientist Gordon Hamilton died on 22 October in Antarctica when his snowmobile fell into a crevasse. Hamilton, who was 50 years old, was an associate research professor in the glaciology group of the Climate Change Institute at the University of Maine. His work centered on how ice sheets behave and affect the climate system. Hamilton and his research team were camped on White Island in the Ross Archipelago in a heavily crevassed area known as the Shear Zone. The cause of the accident is currently under investigation.