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Ice loss to add 0.4C to global temperatures: Study

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The loss of billions of tons of ice from Earth’s frozen spaces is likely to increase global temperatures by an additional 0.4 degrees Celsius, according to research Tuesday highlighting the danger of a “vicious circle” of warming.

Arctic summer sea ice levels have declined by more than 10 percent each decade since the late 1970s and mountain glaciers have shed roughly 250 billion tons of ice annually over the last century.

Ice loss from the West Antarctic and Greenland ice sheets is accelerating and already outstripping what scientists until recently believed to be the worst-case melt scenarios.

Decades of studies have sought to quantify how Earth’s melting ice will contribute to sea level rise — Antarctica and Greenland alone contain enough frozen water to boost oceans’ height by around 60 meters.

But little research has tried to predict how ice loss will add to the already 1.0 degree C of global warming emissions from fossil fuels since the start of the Industrial Era.

Scientists at Germany’s Potsdam Institute for Climate Impact Research (PIK) used a climate model that includes components on atmosphere, ocean, sea- and land-ice data to predict temperature change from ice loss under a variety of emissions scenarios.

They found that under current levels of atmospheric CO2 — roughly 400 parts per million — the melting of Arctic sea ice, mountain glaciers and the polar ice caps would raise temperatures by 0.4C.

That’s on top of the 1.5C of warming our current emissions levels have rendered all but inevitable, and the safer cap on global warming aimed for in the Paris climate accord.

The main driver of temperature gain from ice loss would be due to a process known as albedo feedback, in which heat reflective bright ice is replaced by absorbent darker sea water and/or soil.

“If global ice masses shrink, this changes how much of the sunlight that hits the Earth’s surface is reflected back into space,” said lead author Nico Wunderling.

He likened the albedo effect to wearing either white or black clothes in summer.

“If you wear dark, you heat up more easily,”  Wunderling noted.

This is one of Earth’s so-called climate “feedback loops”, in which increased temperatures lead to further ice loss, which in turn further increases temperatures.

Tipping point

Other ways that temperatures would rise further as ice receded include increased water vapor in the atmosphere, increasing the greenhouse effects, said authors of the study published in Nature Communications.

Looking solely at Arctic sea ice — which unlike polar ice caps might be totally absent during summer months within decades — they found its melt would contribute 0.2C to global temperatures alone.

The largest ice masses in Greenland and West Antarctica, by comparison, are huge and will likely take centuries to melt fully even if emissions continue their unabated growth.

But the authors highlighted the risk that those enormous bodies of frozen water could soon reach a point of no return as temperatures creep ever higher.

Given the unknowns surrounding ice cap tipping points, Wunderling told AFP it would be best to act in “a risk-averse” way and try to drag down emissions as soon as possible.

“With continued global warming, it becomes more and more likely that we cross tipping points -– not just in the ice-sheets, but also in other parts of the climate system,” he said.

“If the Paris Agreement is fulfilled we can avoid many of the strongest and potentially irreversible impacts on Earth’s ice masses, the global climate and humanity.”

 

 

 

Source:- The Jakarta Post – Jakarta Post

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Scientists find neutrinos from star fusion for the first time – Engadget

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Neutrino detection in INFN Gran Sasso Laboratories' facility


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Researchers have effectively confirmed one of the most important theories in star physics. NBC News reports that a team at the Italian National Institute for Nuclear Physics has detected neutrinos traced back to star fusion for the first time. The scientists determined that the elusive particles passing through its Borexino detector stemmed from a carbon-nitrogen-oxygen (CNO) fusion process at the heart of the Sun.

This kind of behavior had been predicted in 1938, but hadn’t been verified until now despite scientists detecting neutrinos in 1956. Borexino’s design was crucial to overcoming that hurdle — its “onion-like” construction and ongoing refinements make it both ultra-sensitive and resistant to unwanted cosmic radiation.

It’s a somewhat surprising discovery, too. CNO fusion is much more common in larger, hotter stars. A smaller celestial body like the Sun only produces 1 percent of its energy through that process. This not only confirms that CNO is a driving force behind bigger stars, but the universe at large.

That, in turn, might help explain some dark matter, where neutrinos could play a significant role. Scientist Orebi Gann, who wasn’t involved in these findings, also told NBC that an asymmetry between neutrinos and their relevant antiparticles might explain why there isn’t much known antimatter in the universe. To put it another way, the findings could help answer some of the most basic questions about the cosmos.

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Johnny Fresco closed after employee tests positive – KitchenerToday.com

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A staff member at Johnny Fresco’s has tested positive for COVID-19, leading the restaurant to temporarily close its doors.

According to their Facebook post, the Waterloo restaurant was closed as of Tuesday for the safety of their customers and staff.

The affected employee was last in the restaurant during the lunch shift on Friday.

They say they will be following the guidance of Public Health, and thank the community for their support throughout the years and during this difficult time under the pandemic.

They will post an update to Facebook and Instagram once they feel its safe to reopen.

Johnny Fresco To our Friends and Customers, We are sad to announce that Johnny Fresco will be temporarily closed…

Posted by Johnny Fresco’s on Wednesday, 25 November 2020

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Calgary man captures photo of SpaceX Dragon docked at the International Space Station – Calgary Herald

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When Shafqat Zaman takes photos of the International Space Station (ISS) from Calgary, it may help that he’s about 1 kilometre closer than photographers shooting from sea level.

However, the ISS is still about 399 kilometres away, and moving at a speed of about 7.66 kilometres per second relative to the ground. However you measure it, snapping a shot of the orbiting laboratory is an incredible feat.

Zaman captured this shot on Wednesday evening. It features a clear view of the SpaceX Dragon capsule, which lifted off on Nov. 15 and docked with the station about 27 hours later. It’s the white cone-shaped object on the left side, near the middle.

The SpaceX Dragon capsule is the bright white cone on the left of the ISS. Photo by Shafqat Zaman /Submitted

This wasn’t his first snapshot of the most expensive object ever constructed. Zaman captured several images of the ISS showing different angles as it passed overhead in late September.

A series of 3 images of the ISS taken as it passed over Calgary in September 2020. Photo by Shafqat Zaman /Submitted

He also captured this stunning transit of the ISS in front of the sun.

A series of shots of the ISS passing in front of the sun. Photo by Shafqat Zaman /Submitted

Zaman said he uses an 8″ Meade SCT telescope with a Canon M5 camera.

Zaman’s telescope. Photo by Shafqat Zaman

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