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New study predicts Arctic Ocean will be 'ice free' in summer by middle of this century – Whitecourt Star

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The forecast may not alter even if the world cuts current CO2 emissions as best it can

The new study on Artic Ocean ice predicts that a stunning change will have happened even before the middle of the current century.

Dirk Notz

A startling new analysis of climate models, made by scientists at Montreal’s McGill University and elsewhere, has made a grim prediction — within decades, the Arctic Ocean will hold practically no summer ice at all.

Science Alert reports that the new study predicts the stunning change will have happened even before the middle of the current century, and the forecast may not alter even if the world cuts current CO2 emissions as best it can.

The study was published in the journal Geophysical Research Letters. In it, scientists looked at 40 different climate models that mimic how sea ice patterns will evolve in the Arctic in the coming decades. The researchers used various mocked-up situations, including some where emissions continued as they are (offering little or no protection to the climate) and some where the emissions were sharply reduced.

The state-of-the-art models used were from the World Climate Research Program’s Coupled Model Intercomparison Project, known as CMIP6.

In the majority of simulations, the Arctic Ocean loses practically all of its summertime ice, whatever the measures taken, by 2050. The paper predicts:

“The CMIP6 models simulate a large spread for when Arctic sea-ice area is predicted to drop below 1 million km2, such that the Arctic Ocean becomes practically sea-ice free.

“However, the clear majority of all models, and of those models that best capture the observed evolution, project that the Arctic will become practically sea-ice free in September before the year 2050 at future anthropogenic CO2 emissions of less than 1,000 [gigatonnes of] CO2 above that of 2019 in all scenarios.”

Scientists have sounded the alarm on a devastating depletion of ice in the Arctic for decades. But the speed of the deterioration under the new models has been an eye-opener.

Dirk Notz, a polar geophysicist from the University of Hamburg in Germany, told Science Alert:

“If we reduce global emissions rapidly and substantially, and thus keep global warming below 2 °C relative to pre-industrial levels, Arctic sea ice will nevertheless likely disappear occasionally in summer even before 2050. This really surprised us.”

In a release on the study, the McGill University team pointed out that although the ice did deplete under low emissions scenarios, “How often the Arctic will lose its sea-ice cover in the future critically depends on future CO2 emissions, the study shows.”

Ice was expected, under high-emissions modelling, to vanish rapidly. But that was not expected to always be the case under low-emissions scenarios. And humans must play their part.

“If emissions are reduced rapidly, ice-free years only occur occasionally,” the McGill release reads. “With higher emissions, the Arctic Ocean will become ice-free in most years. This tells us that humans still determine how often the Arctic Ocean will be ice-free in the summer, depending on our future level of emissions.”

“While the Arctic sea-ice extent is decreasing during this transition to an ice-free Arctic, the year-to-year variability in extent greatly increases, making life more difficult for local populations and ice-dependent species,” says Bruno Tremblay, associate professor in the Department of Atmospheric and Oceanic Sciences at McGill.

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An Asteroid Bigger Than The Empire State Building Poses ‘No Danger’ On Saturday Night, Says NASA – Forbes

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A huge near-Earth asteroid will pass our planet tonight at a safe distance of 3.2 million miles, according to NASA.

After a spate of doom-laden headlines the space agency felt the need yesterday to update a previous post about near-Earth asteroids with the following note:

“Asteroid 2002 NN4 will safely pass by the Earth on June 6 at a distance of approximately 3.2 million miles (5.1 million kilometers), about 13 times further away from the Earth than the Moon is. There is no danger the asteroid will hit the Earth.”

Asteroid 2002 NN4’s closest approach to Earth will be at 11:20 p.m. EDT. on Saturday, June 6, 2020.

NASA also tweeted the same advice:

NASA Asteroid Watch then tweeted this image of the asteroid’s trajectory:

How big is Asteroid 2002 NN4?

Asteroid 2002 NN4 is huge. Measuring between 820 feet and 1,870 feet (250 meters to 570 meters) according to Space.com. New York City’s Empire State Building is 443.2 meters tall, including its antenna.

That’s over a dozen times bigger than the asteroid that exploded over Chelyabinsk, Russia, in 2013. That was the biggest meteor for over a century.

Would asteroid 2002 NN4 be dangerous if it hit Earth?

Yes—asteroid 2002 NN4 is city-killer size, but it’s not going to cause any harm to anyone.

Wishing you clear skies and wide eyes.

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Crew Dragon with two NASA astronauts docks to ISS – TASS

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NEW YORK, May 31. /TASS/. The Crew Dragon spacecraft with Doug Hurley and Bob Behnken on board has successfully docked to the International Space Station (ISS), as follows from a NASA broadcast on Sunday.

The spacecraft began approaching the ISS about two hours before docking than was carried out 10:16 ahead of the schedule. The Crew Dragon spacecraft was launched using the SpaceX Falcon 9 rocket at 22.22 pm Moscow time on May 30 from the Cape Canaveral, Florida.

Crew Dragon is a configuration of the cargo spacecraft Dragon, which had already delivered cargoes to the ISS. A Falcon-9 rocket put the cargo vehicle in space on March 2. Its docking with the ISS was carried out automatically the next day.

NASA stopped crewed flights in 2011 after the Space Shuttle program came to an end. From that moment on all astronauts were delivered to the ISS and back by Russia’s Soyuz spacecraft. Originally the Untied States was to start using commercial spacecraft for crewed missions in 2017.

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Toddler could be battling rare syndrome in response to COVID-19 – Winnipeg Free Press

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More than a month after testing positive for COVID-19, a Winnipeg toddler is fighting another illness – a possible rare inflammatory syndrome that could be part of the body’s reaction to new viruses.

The girl’s mother told CBC News doctors are trying to find out whether the one-year-old has developed Kawasaki disease, or multi-system inflammatory syndrome in children, now that she is negative for COVID-19 but is still seriously ill.

To read more of this story first reported by CBC News, click here.

The Winnipeg Free Press and CBC Manitoba recognize each other as trusted news sources. This content is made available to our readers as part of an agreement to collaborate to better serve our community. Any questions about CBC content should be directed to: talkback@cbc.ca

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