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Record-size ozone hole over Arctic now healed and closed – DW (English)

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An “unprecedented” ozone depletion in the northern hemisphere has healed, but unlikely due to the impacts of worldwide coronavirus lockdowns, scientists say. The hole had been about three times the size of Greenland.

A “record-level” ozone hole over the Arctic – the biggest since 2011 –  has now closed, the UN World Meteorological Organization (WMO) said on Friday.

The phenomenon was driven by ozone-depleting substances still in the atmosphere and a very cold winter in the stratosphere — the layer of the earth’s atmosphere that lies between 10 and 50 kilometers (six to 31 miles)  above the earth — Reuters cited WMO spokeswoman Clare Nullis saying at a UN briefing in Geneva.

The image shows the Arctic ozone hole at its peak in March

“These two factors combined to give a very high level of depletion which was worse than the one we saw in 2011. It’s now back to normal again … the ozone hole has closed,” she said.

Scientists monitoring the hole at the Copernicus Atmospheric Monitoring Service (CAMS), a European Union earth observation program, announced the closure last week.

‘Unrelated to COVID’

Despite coronavirus lockdowns resulting in a significant reduction in air pollution, Nullies said the occurrence of the hole healing “was completely unrelated to COVID.”

CAMS also announced that the phenomenon probably had nothing to do with the pandemic.

“Actually, COVID19 and the associated lockdowns probably had nothing to do with this,” CAMS tweeted. “It’s been driven by an unusually strong and long-lived polar vortex, and isn’t related to air quality changes.”

Ten times the size of Greenland

A German scientist had detected the depletion only a month ago in what he said was the biggest hole in the ozone layer above the North Pole.

“In the areas where the thickness of the ozone layer is at its maximum, the loss is around 90%,” the German press agency dpa quoted Markus Rex — head of the department for atmospheric physics at the German Alfred-Wegener Institute — in March. It’s equivalent to an area three times the size of Greenland.

Read more: What happened to the ozone layer?

In total, an area of 20 million square kilometres, or 10 times the size of Greenland, is affected, even though the loss of ozone is sometimes lower.

Scientists from the European Space Agency (ESA) said that they had predicted the hole to heal as temperatures increased, breaking down the Arctic polar vortex and allowing ozone-depleted air to combine with ozone-rich air from lower altitudes.

According to recent data from the National Aeronautics and Space Administration (NASA), ozone levels above the Arctic reached a record low in March.

Separate from Antarctica ozone hole

The discovery of an ozone hole above Antarctica in 1985 led to the approval of the Montreal Protocol two years later,in which 197 countries agreed to phase out chemicals like chlorofluorocarbons to protect the ozone from further damage and decrease the size of the hole.

In 2019, it reached its smallest extent in about 30 years.
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Scientists produce diamonds in minutes at room temperature – MINING.com

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“Natural diamonds are usually formed over billions of years, about 150 kilometres deep in the Earth where there are high pressures and temperatures above 1,000 degrees Celsius,”  Jodie Bradby, professor at The Australian National University and one of the authors of the study, said in a media statement.

“The twist in this story is how we apply the pressure. As well as very high pressures, we allow the carbon to also experience something called ‘shear’ – which is like a twisting or sliding force. We think this allows the carbon atoms to move into place and form Lonsdaleite and regular diamond.” 

The RMIT team’s pictures showed that the regular diamonds only form in the middle of these Lonsdaleite veins under this new method. (Image courtesy of the Royal Melbourne Institute of Technology).

To observe and understand how this process works, the researchers used advanced electron microscopy techniques to capture solid and intact slices from the experimental samples to create snapshots of how the two types of diamonds formed.

The pictures showed that the regular diamonds only form in the middle of Lonsdaleite veins under this new method.

“Seeing these little ‘rivers’ of Lonsdaleite and regular diamond for the first time was just amazing and really helps us understand how they might form,” Dougal McCulloch, the study’s lead author and a professor at the Royal Melbourne Institute of Technology, said. 

According to the scientists, Lonsdaleite has the potential to be used for cutting through ultra-solid materials on mining sites. As such, they said that creating more of this rare diamond is the long-term aim of their work.

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Siemens, Deutsche Bahn launch local hydrogen trains trial – The Guardian

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MUNICH (Reuters) – Siemens Mobility and Deutsche Bahn have started developing hydrogen-powered fuel cell trains and a filling station which will be trialled in 2024 with view to replace diesel engines on German local rail networks.

The prototype, to be built by Siemens, is based on electric railcar Mireo Plus which will be equipped with fuel cells to turn hydrogen and oxygen into electricity on board, and with a battery, both companies said.

Siemens mobility chief executive Michael Peter told Reuters the train combined the possibility to be fed by three sources in a modular system – either by the battery, the fuel cell or even existing overhead lines, depending on where it would run.

German railway operator Deutsche Bahn has not electrified 40% of its 33,000 kilometre (km) long network, on which it runs 1,300 fossil-fuel emitting diesel locomotives.

Rail transport must be decarbonised over the long-term under European Union and national climate targets.

“Our hydrogen trains are able to replace diesel-fuelled trains in the long term,” Peter said.

The new prototype will be fuelled within 15 minutes, have a range of 600 km and a top speed of 160 km/hour.

It will be tested between Tuebingen, Horb and Pforzheim in Baden Wuerttemberg state.

The main target market are operators of regional networks that typically re-order lots of 10 to 50 trains, Peter said.

“We see a market potential of 10,000-15,000 trains in Europe that will need to be replaced over the next 10-15 years, with 3,000 alone in Germany,” he said.

Each train will cost between five and 10 million euros ($5.9-$11.9 million), creating a market potential of 50-150 billion euros overall.

The Berlin government expects green hydrogen to become competitive with fossil fuels over the long term and to play a key role in decarbonising industry, heating and transport.

(Reporting by Joern Poltz in Munich and Vera Eckert in Frankfurt, editing by David Evans)

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The impossible choice Canada’s seniors face this winter – 95.7 News

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In today’s Big Story podcast, we want elderly Canadians, who are heightened risk from COVID-19, to be safe. For much of the past eight months, that has meant hundreds of thousands of grandparents haven’t seen their grandkids, parents haven’t seen their children, or their siblings — and for many of them, this has harmed them as much as a bout with the virus might.

We all want our elderly loved ones to be around forever, but even forgetting about COVID-19, they won’t be. And as they face another four to six months without much contact or support, many of them are wondering if they might not choose to take the risk with the time they have left.

GUEST: Christina Frangou, science and health writer

You can subscribe to The Big Story podcast on Apple Podcasts, Google and Spotify

You can also find it at thebigstorypodcast.ca.

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