Fewer trees, less undergrowth: Study says wildfires changing boreal forest - EverythingGP - Canada News Media
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Fewer trees, less undergrowth: Study says wildfires changing boreal forest – EverythingGP

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The differences were striking.

The short-interval stands were far more open with fewer trees. Aspens dominated instead of conifers. Growth beneath the trees — shrubs and grasses that cover a normal forest floor — was far less luxuriant with many fewer species. Areas of exposed mineral soil, where all organic material had been burned off, were larger and more common.

They felt completely different.

“You have a landscape where you’re surrounded by short, stunted trees,” Whitman said. “You have a crust of lichen or some sparse grasses. It’s almost like walking through the edge of a prairie where you’re shifting from a grassland into a forest edge.

“At a lot of the long-interval sites, you’ve got quite dense conifers, closer together. You’ve got moss on the ground and flowers and shrubs. It’s more what looks like a young forest.”

The boreal forest has evolved for fire. Many of its tree species need it to germinate.

Normally, fires don’t come around more often than every 30 years and often much longer. The lack of fuel in recently burned stands helps regulate that frequency.

Climate change is breaking those rules, Whitman said.

“We’re experiencing more hot, dry windy days — the main trigger for large fire years. As more years experience more extreme fire weather, (the blazes) are able to overwhelm that resistance that recently burned sites have.”

Nor are the parkland-like areas likely to evolve into a conventional boreal forest. Previous studies have found that the look of a forest is set early after a fire.

“Immediate post-fire condition is an extremely strong predictor of what the stand will look like further down the road,” said Whitman.

Whitman emphasizes that short-interval stands in her research are still small and most stretches of boreal forest burned in recent wildfires are regrowing normally. Wetlands are also less affected by short-interval fires than drier regions.

She said the forestry industry is unlikely to be affected any time soon — although forest-dependent animals such as caribou and songbirds will feel impacts.

And those impacts are growing.

“With a longer fire season, larger fires, more of the landscape burning each year, the likelihood of encountering a recently burned area increases. We’re undergoing a shortening of the fire frequency in the boreal forest.”

This report by The Canadian Press was first published Jan. 12, 2010.

— Follow Bob Weber @row1960 on Twitter

Bob Weber, The Canadian Press

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Asteroid twice the size of Big Ben to skim past Earth today – Khaleej Times

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Published on January 20, 2020 at 10.36

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NASA is closely monitoring an asteroid with an estimated diameter of about 755 feet – larger than the Golden Gate Bridge tower or more than twice the height of London’s Big Ben – that is currently heading towards Earth and is expected to skim past the planet on Monday. Flying towards the planet at a speed of over 61,500 miles per hour, the Near-Earth Object (NEO) is big enough to destroy an entire city if collides with the Earth. The approaching asteroid has been identified as 2020 AQ1.

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Earlier in 2019, three huge asteroids flew dangerously close to the Earth on November 10, NASA had revealed.

The biggest of the three space rocks, dubbed 2018 VR1, was predicted to measure up to 30 metres wide – as big as a blue whale.

The first asteroid, dubbed 2018 VS1, passed our planet at around 14:03 GMT (6:03pm Dubai time) and was 861,700 miles away from Earth during its closest approach. Scientists estimated it to be between 13-28 metres wide, five times as tall as a giraffe.

In March of last year, extremely bright fireballs were spotted in UAE skies.

Eng Mohammed Shawkat, Director of the International Astronomy Centre in Abu Dhabi, told Khaleej Times that the appearance of the fireball has been filmed by a special network of astronomical cameras.

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Another bright fireball, the second in March, was spotted in UAE skies late night on March 12 at around 11:50pm, local time.

This was actually the second fireball to be spotted in the UAE skies in one week, after the first one appeared on March 5, at exactly 7:40:11, according to a senior official.

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According to Express.co.uk, the asteroid will make its closest Earth approach on January 20 at around 2.54 am EST (11.54am UAE time, 1.24 pm India time). The European Space Agency (ESA) has identified 21,655 NEO asteroids and 109 NEO comets. The asteroid will hurtle past the planet on what astronomers have described as a close approach trajectory.

Last September, a pair of asteroids flew past the Earth.

Both of these asteroids are passing at about 14 lunar distances from the Earth, or about 3.5 million miles away, but small asteroids pass by Earth this close all the time, said NASA’s Planetary Defence Officer Lindley Johnson.

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Photos: SpaceX purposely fails rocket to test crew capsule safety system – Spaceflight Now

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Credit: Katie Darby

SpaceX simulated an in-flight emergency Sunday to verify the company’s Crew Dragon spacecraft has the capability to catapult itself away from a failing Falcon 9 rocket.

The in-flight abort test demonstrated the human-rated capsule can safely and rapidly fly away from a Falcon 9 rocket experiencing a failure.

As intended, the Falcon 9’s engines prematurely shut down around 84 seconds after liftoff Sunday from the Kennedy Space Center. The automated Crew Dragon capsule fired its own thrusters to escape the rocket before it disintegrated in an orange fireball high over Florida’s Space Coast.

After a one-day delay due to rough seas in the splashdown zone — and a two-and-a-half-hour hold Sunday to wait for improved winds — the Crew Dragon spacecraft lifted off on top of a SpaceX Falcon 9 rocket at 10:30 a.m. EST (1530 GMT) Sunday from pad 39A at Kennedy, the same launch pad once used by NASA’s Saturn 5 moon rockets and space shuttles.

The 215-foot-tall (65-meter) rocket flew off the launch pad powered by nine kerosene-fueled Merlin 1D engines and pitched on an easterly trajectory from the Florida spaceport.

The Falcon 9 surpassed the speed of sound in less than a minute, and the Crew Dragon’s pre-programmed escape sequence initiated around 84 seconds after liftoff, when the rocket was at an altitude of roughly 62,000 feet (19 kilometers).

SpaceX’s Falcon 9 booster disintegrated in a fireball — as expected — seconds after the Crew Dragon capsule fired away from the top of the rocket in an in-flight escape demonstration Sunday. Credit: Spaceflight Now

The abort was triggered soon after the point in the launch sequence where the booster and capsule experience the most extreme aerodynamic pressures.

While the nine Merlin engines on the Falcon 9 rocket cut off in response to the escape command, nearly 130,000 pounds of thrust from eight SuperDraco engines pushed the Crew Dragon rapidly away from the top of the launcher.

The rocket disintegrated in a fireball high over the Atlantic Ocean — as officials expected — as the crew capsule sped away from the top of the launcher with a powerful boost from the eight escape engines.

SpaceX said the capsule, and two mannequins seated inside, accelerated at about 3.5Gs during the abort, a relatively gentle ride for astronauts in good physical condition.

The capsule later deployed parachutes and splashed down in the Atlantic for recovery by SpaceX vessels.

Read our full story for details on the abort test.

Additional photos of the Falcon 9’s liftoff and the Crew Dragon abort are posted below.

The Falcon 9 rocket and Crew Dragon spacecraft lifted off from pad 39A at the Kennedy Space Center at 10:30 a.m. EST (1530 GMT) Sunday. Credit: Stephen Clark / Spaceflight Now
Credit: Katie Darby
Credit: Katie Darby
Credit: Katie Darby
Credit: Katie Darby
Credit: Spaceflight Now
Debris from the Falcon 9 booster plunges toward the Atlantic Ocean. Credit: Spaceflight Now

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Follow Stephen Clark on Twitter: @StephenClark1.

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Physicists Finally Observe a Link Between Quantum Criticality And Entanglement – ScienceAlert

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We know that the realm of quantum physics is science operating at a mind-bogglingly small scale, thus watching quantum interactions happen is always exciting. Now, physicists have managed to observe billions upon billions of entangled electrons passing through a metal film.

The film is a mix of ytterbium, rhodium and silicon, and is what’s known as a ‘strange metal’, one that doesn’t act as expected at very low temperatures.

“With strange metals, there is an unusual connection between electrical resistance and temperature,” explained physicist Silke Bühler-Paschen from Vienna University of Technology in Austria.

“In contrast to simple metals such as copper or gold, this does not seem to be due to the thermal movement of the atoms, but to quantum fluctuations at the absolute zero temperature.”

These fluctuations represent a quantum criticality – that point between quantum states which are the equivalent of transition between liquids, solids and gases in classical physics; the team says this cascade of electrons is the best evidence yet of a link between quantum criticality and entanglement.

The terahertz spectrometer used to measure entanglement. (Jeff Fitlow/Rice University)

“When we think about quantum entanglement, we think about small things,” says physicist Qimiao Si, from Rice University. “We don’t associate it with macroscopic objects.”

“But at a quantum critical point, things are so collective that we have this chance to see the effects of entanglement, even in a metallic film that contains billions of billions of quantum mechanical objects.”

The experiments Bühler-Paschen, Si and colleagues ran were incredibly challenging from many levels – from the highly complex materials synthesis required to create the strange metal, to the delicate terahertz spectroscopy required to observe the electrons.

Ultimately, after a painstaking process, the team found what they were looking for: the tell-tale sign of quantum criticality known as frequency over temperature scaling.

“Conceptually, it was really a dream experiment,” says Si. “Probe the charge sector at the magnetic quantum critical point to see whether it’s critical, whether it has dynamical scaling.”

“If you don’t see anything that’s collective, that’s scaling, the critical point has to belong to some textbook type of description. But, if you see something singular, which in fact we did, then it is very direct and new evidence for the quantum entanglement nature of quantum criticality.”

What all of this high-level physics means is a lot of potential: potential quantum advancements in computing, communications and more. Scientists have hypothesised about a link between quantum entanglement and quantum criticality before, but now it’s been observed.

The study of quantum states is still in its very early stages, but it could hold the key to all kinds of weird science, like high-temperature superconductivity – which is also believed to be underpinned by quantum criticality.

Understanding how these quantum phases switch gives us a better chance of being able to control them in the future – and although that’s still a long way off, it just got a little closer.

“Our findings suggest that the same underlying physics – quantum criticality – can lead to a platform for both quantum information and high-temperature superconductivity,” says Si. “When one contemplates that possibility, one cannot help but marvel at the wonder of nature.”

The research has been published in Science.

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