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3 reasons the Arctic freeze is unseasonably late and why it matters

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With the setting of the sun and the onset of polar darkness, the Arctic Ocean would normally be crusted with sea ice along the Siberian coast by now. But this year, the water is still open.

I’ve watched the region’s transformations since the 1980s as an Arctic climate scientist and, since 2008, as director of the National Snow and Ice Data Center. I can tell you, this is not normal. There’s so much more heat in the ocean now than there used to be that the pattern of autumn ice growth has been completely disrupted.

To understand what’s happening to the sea ice this year and why it’s a problem, let’s look back at the summer and into the Arctic Ocean itself.

Siberia’s 100-degree summer

The summer melt season in the Arctic started early. A Siberian heat wave in June pushed air temperatures over 100 degrees Fahrenheit at Verkhoyansk, Russia, for the first time on record, and unusual heat extended over much of the Arctic for weeks.

The Arctic as a whole this past summer was at its warmest since at least 1979, when satellite measurements started providing data allowing for full coverage of the Arctic.

With that heat, large areas of sea ice melted out early, and that melting launched a feedback process: The loss of reflective sea ice exposed dark open ocean, which readily absorbs the sun’s heat, promoting even more ice melt.

The Northern Sea Route, along the Russian coast, was essentially free of ice by the middle of July. That may be a dream for shipping interests, but it’s bad news for the rest of the planet.

Warmth sneaks in underwater

The warm summer is only part of the explanation for this year’s unusual sea ice levels.

Streams of warmer water from the Atlantic Ocean flow into the Arctic at the Barents Sea. This warmer, saltier Atlantic water is usually fairly deep under the more buoyant Arctic water at the surface. Lately, however, the Atlantic water has been creeping up. That heat in the Atlantic water is helping to keep ice from forming and melting existing sea ice from below.

It’s a process called “Atlantification”. The ice is now getting hit both from the top by a warming atmosphere and at the bottom by a warming ocean. It’s a real double whammy.

While we’re still trying to catch up with all of the processes leading to Atlantification, it’s here and it’s likely to get stronger.

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Climate change’s assault on sea ice

In the background of all of this is global climate change.

The Arctic sea ice extent and thickness have been dropping for decades as global temperatures rise. This year, when the ice reached its minimum extent in September, it was the second lowest on record, just behind that of 2012.

As the Arctic loses ice and the ocean absorbs more solar radiation, global warming is amplified. That can affect ocean circulation, weather patterns and Arctic ecosystems spanning the food chain, from phytoplankton all the way to top predators.

On the Atlantic side of the Arctic, open water this year extended to within 5 degrees of the North Pole. The new Russian Icebreaker Arktika, on its maiden voyage, found easy sailing all the way to the North Pole. A goal of its voyage was to test how the nuclear-powered ship handled thick ice, but instead of the hoped-for 3-meter-thick ice, most of the ice was in a loose pack. It was little more than 1 meter thick, offering little resistance.

For sea ice to build up again this year, the upper layer of the Arctic Ocean needs to lose the excess heat it picked up during summer.

The pattern of regional anomalies in ice extent is different each year, reflecting influences like regional patterns of temperature and winds. But today, it’s superimposed on the overall thinning of the ice as global temperatures rise. Had the same atmospheric patterns driving this year’s big ice loss off Siberia happened 30 years ago, the impact would have been much less, as the ice was more resilient then and could have taken a punch. Now it can’t.

Is sea ice headed for a tipping point?

The decay of the Arctic sea ice cover shows no sign of stopping. There probably won’t be a clear tipping point for the sea ice, though.

Research so far suggests we’ll stay on the current path, with the amount of ice declining and weather systems more easily disrupting the ice because it’s thinner and weaker than it used to be.

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The bigger picture

This year’s events in the Arctic are just part of the climate change story of 2020.

Global average temperatures have been at or near record highs since January. The West has been both hot and dry – the perfect recipe for massive wildfires – and warm water in the Gulf of Mexico has helped fuel more tropical storms in the Atlantic than there are letters in the alphabet. If you’ve been ignoring climate change and hoping that it will just go away, now would be an appropriate time to pay attention.

Source: – The Conversation US

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Japan capsule with asteroid samples retrieved in Australia – The Chronicle Journal

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TOKYO – Japan’s space agency said its helicopter search team has retrieved a capsule, which is carrying asteroid samples that could explain the origin of life, that landed on a remote area in southern Australia as planned Sunday.

“The capsule collection work at the landing site was completed . . .,” the space agency said in a tweet about four hours after the capsule landed. ”We practiced a lot for today … it ended safe.”

Hayabusa2 had successfully released the small capsule on Saturday and sent it toward Earth to deliver samples from a distant asteroid that could provide clues to the origin of the solar system and life on our planet, the Japan Aerospace Exploration Agency said.

Early Sunday the capsule briefly turned into a fireball as it reentered the atmosphere 120 kilometres (75 miles) above Earth. At about 10 kilometres (6 miles) above ground, a parachute was opened to slow its fall and beacon signals were transmitted to indicate its location.

“It was great … It was a beautiful fireball, and I was so impressed,” said JAXA’s Hayabusa2 project manager Yuichi Tsuda as he celebrated the successful capsule return and safe landing from a command centre in Sagamihara, near Tokyo. “I’ve waited for this day for six years.”

Beacon signals were detected, suggesting the parachute successfully opened and the capsule landed safely in a remote, sparsely populated area of Woomera, Australia, said JAXA official Akitaka Kishi.

About two hours after the capsule’s reentry, JAXA said its helicopter search team found the capsule in the planned landing area. The retrieval of the pan-shaped capsule, about 40 centimetres (15 inches) in diameter, was completed about two hours later.

The fireball could be seen even from the International Space Station. A Japanese astronaut, Soichi Noguchi, who is now on a six-month mission there, tweeted: “Just spotted #hayabusa2 from #ISS! Unfortunately not bright enough for handheld camera, but enjoyed watching capsule!”

Hayabusa2 left the asteroid Ryugu, about 300 million kilometres (180 million miles) away, a year ago. After it released the capsule, it moved away from Earth to capture images of the capsule descending toward the planet as it set off on a new expedition to another distant asteroid.

The capsule descended from 220,000 kilometres (136,700 miles) away in space after it was separated from Hayabusa2 in a challenging operation that required precision control.

JAXA officials said they hoped to conduct a preliminary safety inspection at an Australian lab and bring the capsule back to Japan early next week.

Dozens of JAXA staff have been working in Woomera to prepare for the sample return. They set up satellite dishes at several locations in the target area inside the Australian Air Force test field to receive the signals.

Australian National University space rock expert Trevor Ireland, who was in Woomera for the arrival of the capsule, said he expected the Ryugu samples to be similar to the meteorite that fell in Australia near Murchison in Victoria state more than 50 years ago.

“The Murchison meteorite opened a window on the origin of organics on Earth because these rocks were found to contain simple amino acids as well as abundant water,” Ireland said. “We will examine whether Ryugu is a potential source of organic matter and water on Earth when the solar system was forming, and whether these still remain intact on the asteroid.”

Scientists say they believe the samples, especially ones taken from under the asteroid’s surface, contain valuable data unaffected by space radiation and other environmental factors. They are particularly interested in analyzing organic materials in the samples.

JAXA hopes to find clues to how the materials are distributed in the solar system and are related to life on Earth. Yoshikawa, the mission manager, said 0.1 gram of the dust would be enough to carry out all planned researches.

For Hayabusa2, it’s not the end of the mission it started in 2014. It is now heading to a small asteroid called 1998KY26 on a journey slated to take 10 years one way, for possible research including finding ways to prevent meteorites from hitting Earth.

So far, its mission has been fully successful. It touched down twice on Ryugu despite the asteroid’s extremely rocky surface, and successfully collected data and samples during the 1 1/2 years it spent near Ryugu after arriving there in June 2018.

In its first touchdown in February 2019, it collected surface dust samples. In a more challenging mission in July that year, it collected underground samples from the asteroid for the first time in space history after landing in a crater that it created earlier by blasting the asteroid’s surface.

Asteroids, which orbit the sun but are much smaller than planets, are among the oldest objects in the solar system and therefore may help explain how Earth evolved.

Ryugu in Japanese means “Dragon Palace,” the name of a sea-bottom castle in a Japanese folk tale.

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Follow Mari Yamaguchi on Twitter at https://www.twitter.com/mariyamaguchi

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Hotel Dieu Grace Healthcare to report all positive COVID-19 cases following outbreak – CTV News Windsor

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WINDSOR, ONT. —
Hotel Dieu Grace Healthcare will report all positive cases of COVID-19 as it continues to test patients and staff members following an outbreak at the hospital.

A news release from HDGH says there have now been 11 confirmed patients and 22 healthcare workers who tested positive for the virus.

“The investigation into the outbreak continues, and in some cases it is difficult to categorically assign these positive results to the outbreak at this time,’ the release stated. “In the interests of transparency, we will be reporting ALL positive results, although they may or may not be related to the outbreak.”

HDGH officials said once the investigation is complete they will make any needed adjustments to results allocated to the outbreak and those associated with community spread.

“We recognize the impact that this situation has on our hospital system. We continue to work very closely with the Windsor Essex-County Health Unit and are keeping our acute care partners updated daily,” the release said. “We remain committed to resolving the outbreak as quickly as is safe to do so.”

 HDGH is also pausing all admissions to its inpatient Restorative Care Program. The decision is assessed every 24 hours. All other restrictions continue to be in place.

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Japan spacecraft carrying asteroid samples lands in Australia, agency says – Global News

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Japan’s Hayabusa2 spacecraft successfully released a small capsule on Saturday and sent it toward Earth to deliver samples from a distant asteroid that could provide clues to the origin of the solar system and life on our planet, the country’s space agency said.

The capsule successfully detached from 220,000 kilometres away in a challenging operation that required precision control, the Japan Aerospace Exploration Agency said. The capsule — just 40 centimetres in diameter — has landed Sunday in a remote, sparsely populated area of Woomera, Australia.

“The capsule has been separated. Congratulations,” JAXA project manager Yuichi Tsuda said.

Read more:
Japan declares climate emergency, citing ‘unprecedented damage’ from weather events

Hayabusa2 left the asteroid Ryugu, about 300 million kilometres away, a year ago. After it released the capsule, it moved away from Earth to capture images of the capsule descending toward the planet as it set off on a new expedition to another distant asteroid.

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About two hours later, JAXA said it had successfully rerouted Hayabusa2 for its new mission, as beaming staff exchanged fist and elbow touches at the agency’s command centre in Sagamihara, near Tokyo.

“We’ve successfully come this far, and when we fulfil our final mission to recover the capsule, it will be perfect,” mission manager Makoto Yoshikawa said from the command centre during a livestreaming event.

People who gathered to watch the capsule’s separation at public viewing events across Japan cheered the success. ”I’m really glad that the capsule has been successfully released. My heart was beating fast when I was watching,“ said Ichiro Ryoko, a 60-year-old computer engineer who watched at Tokyo Dome.






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Japanese spacecraft successfully lands on aestroid Ryugu


Japanese spacecraft successfully lands on aestroid Ryugu – Feb 22, 2019

Hayabusa2’s return with the world’s first asteroid subsurface samples comes weeks after NASA’s OSIRIS-REx spacecraft made a successful touch-and-go grab of surface samples from asteroid Bennu. China, meanwhile, announced this week that its lunar lander collected underground samples and sealed them within the spacecraft for their return to Earth, as space developing nations compete in their missions.

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In the early hours of Sunday, the capsule, protected by a heat shield, briefly turned into a fireball as it reentered the atmosphere 120 kilometres above Earth. At about 10 kilometres aboveground, a parachute opened to slow its fall and beacon signals were expected to be transmitted to indicate its location.

JAXA staff have set up satellite dishes at several locations in the target area to receive the signals. They also will use a marine radar, drones and helicopters to assist in the search and retrieval of the pan-shaped capsule.

Australian National University space rock expert Trevor Ireland, who is in Woomera for the arrival of the capsule, said he expected the Ryugu samples to be similar to the meteorite that fell in Australia near Murchison in Victoria state more than 50 years ago.

Read more:
Whatever happened to… the Great East Japan earthquake and Fukushima Daiichi nuclear crisis

“The Murchison meteorite opened a window on the origin of organics on Earth because these rocks were found to contain simple amino acids as well as abundant water,” Ireland said. “We will examine whether Ryugu is a potential source of organic matter and water on Earth when the solar system was forming, and whether these still remain intact on the asteroid.”

Scientists say they believe the samples, especially ones taken from under the asteroid’s surface, contain valuable data unaffected by space radiation and other environmental factors. They are particularly interested in analyzing organic materials in the samples.

Story continues below advertisement

JAXA hopes to find clues to how the materials are distributed in the solar system and are related to life on Earth. Yoshikawa, the mission manager, said 0.1 gram of the dust would be enough to carry out all planned researches.

For Hayabusa2, it’s not the end of the mission it started in 2014. It is now heading to a small asteroid called 1998KY26 on a journey slated to take 10 years one way, for possible research including finding ways to prevent meteorites from hitting Earth.


Click to play video 'Europe, Japan send spacecraft on 7-year journey to Mercury'



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Europe, Japan send spacecraft on 7-year journey to Mercury


Europe, Japan send spacecraft on 7-year journey to Mercury – Oct 20, 2018

So far, its mission has been fully successful. It touched down twice on Ryugu despite the asteroid’s extremely rocky surface, and successfully collected data and samples during the 1 1/2 years it spent near Ryugu after arriving there in June 2018.

In its first touchdown in February 2019, it collected surface dust samples. In a more challenging mission in July that year, it collected underground samples from the asteroid for the first time in space history after landing in a crater that it created earlier by blasting the asteroid’s surface.

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Asteroids, which orbit the sun but are much smaller than planets, are among the oldest objects in the solar system and therefore may help explain how Earth evolved.

Ryugu in Japanese means “Dragon Palace,” the name of a sea-bottom castle in a Japanese folk tale.

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Associated Press writers Dennis Passa in Brisbane, Australia, and Chisato Tanaka in Tokyo contributed to this report.

© 2020 The Canadian Press

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