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Earth has a 27.5-million-year 'pulse' of major geological events, says study – CBC.ca

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Hello, Earthlings! This is our weekly newsletter on all things environmental, where we highlight trends and solutions that are moving us to a more sustainable world. (Sign up here to get it in your inbox every Thursday.)

This week:

  • Earth has a 27.5-million-year ‘pulse’ of major geological events, says study
  • The worldwide demand for sand
  • Maritime startup invents Lego-style bricks made from recycled plastic

Earth has a 27.5-million-year ‘pulse’ of major geological events, says study

(Earth Sciences and Image Analysis Laboratory, NASA Johnson Space Center/Associated Press)

The Earth behaves cyclically, and major geologic events like earthquakes and volcanic eruptions that could lead to extinctions cluster in cycles, a new study has found.

The research team, led by Michael Rampino, a professor in New York University’s department of biology, even has a special name for it.

“All of these things, when you add them all together, seem to occur in pulses,” said Rampino. “Not at random, but in pulses.”

Rampino and his colleagues looked at recently published data about a period of 89 geological events in the past 260 million years in order to identify peaks in which they occurred.

These so-called pulses have a cycle of happening roughly every 27.5 million years. 

“It means that there’s an ongoing cycle running through all of these various and seemingly unrelated geological events,” said Rampino.

The research team analyzed mass geological episodes, such as fluctuations in the global sea level caused by changes in sea-floor spreading rates, that affected sea and land organisms. The extinction of dinosaurs dating back 66 million years — or three cycles ago — was one of the events the researchers looked at to find a pattern.

The research notes how many of these catastrophic events seem to happen during the same period. Giant earthquakes and volcanic eruptions still happen outside these peaks, and scientists are still unsure what is causing them. 

According to the study, the most recent cluster of disastrous geological episodes was about seven to 10 million years ago, so it is safe to say that Earth is at least 15 million years away from experiencing this series of catastrophic events that will likely wipe out most, if not all, humankind. 

If you were wondering, human-induced climate change is separate from these cycles, but anything we do to damage the environment will continue to affect our living conditions. 

“I don’t know what we could do 20 million years from now,” said Rampino. “But for now, these cycles don’t seem to be in the control of human beings.”

Even if humans survive and develop the technology to deal with these events millions of years from now, Rampino said the Earth’s pulse will keep on beating. 

The geologist said that for a long time, scientists lacked accurate enough age data to make co-ordinated, statistics-based calculations about these geological events.

“Back in the early 20th century, no one had very good evidence to show whether they were cycles or not,” said Rampino. “And many or most geologists thought that these cycles were random.”

Other research studies have proposed cycles for various geological occurrences on a global scale, like volcanic activity, leading to climate changes.

Rampino himself published studies in the past that looked at the cycle of some of these events separately. In September 2020, his team found the same interval of 27.5 million years in a study about the mass extinction cycle of four-legged land animals.

It was difficult for scientists to perform any quantitative investigations until a couple of years ago. With the improvement of radio-isotope dating techniques and updates in the geologic timescale, new data has been compiled that makes it possible to search for correlations in these events accurately.

Geologists want to know how the Earth behaves, and this evidence shows that the Earth has behaved in a cyclical way for a long time, according to Rampino.

The researcher said this is an important finding because the question isn’t why, but how these things happen.

“You need to know the age of these events very precisely,” said Rampino. “Now [we] can see there’s a periodicity.”

Thaïs Grandisoli

Reader feedback

In response to Emily Chung’s story on Canadian swimsuit designers using recycled plastic, Mark Hambridge wrote:

“Of course, the whole swimsuit problem goes away if you use the swimwear we are born with: fits perfectly, lightweight, colour matched so no tan lines, drip, sun or air dry, can be washed with household soap (dry cleaning especially forbidden). Unfortunately, social issues make it difficult to use in urban areas.”

Daniel Zung, meanwhile, addressed Colin Butler’s story on helium balloons ending up in the Great Lakes. “It is probably best not to be inflating balloons with helium to be released. While apparently the shortage of helium has decreased over the past year, potentially due to fewer parties, once more balloons are demanded, helium prices might rise as demand for the gas returns. Best to keep helium for … science and manufacturing where as a society we might have better use of the gas rather than polluting the environment by using balloons (in general).”

Old issues of What on Earth? are right here.

There’s also a radio show and podcast! Protests against old-growth logging in British Columbia have drawn international attention to the importance of ancient forests. This week, What on Earth guest host Lisa Johnson hears about the role these trees play in fighting climate change. What on Earth airs Sunday at 12:30 p.m., 1 p.m. in Newfoundland. Subscribe on your favourite podcast app or hear it on demand at CBC Listen.


The Big Picture: Sand mining

In response to a recent story we did on the push to make more environmentally friendly concrete, several readers pointed out the ecological impact of one of concrete’s biggest ingredients: sand. Fact: no commodity is mined more than sand. No mineral or metal comes close. Its greatest use is in concrete, but sand can also be found in everything from glass to toothpaste. As countries continue to urbanize, sand use is only expected to go up. While we have deserts that would seem to contain more than enough of the grainy stuff, the sand found in places like the Sahara is so weathered and dry that it is unusable for applications like concrete. Prime sand is found along shorelines (such as the Congo River near Brazzaville, Republic of Congo, as in the photo below). But in meeting the global demand for sand, mining operations are eroding coastlines and destroying ecosystems.

(Marco Longari/AFP via Getty Images)

Hot and bothered: Provocative ideas from around the web


Maritime startup invents Lego-style bricks made from recycled plastic

(Submitted by Dustin Bowers)

In a social media video shot in a shipping container in his backyard, Dustin Bowers can be seen wearing protective goggles and throwing plastic garbage into a funnel that grinds it up into shreds.

From these shreds, the Hampstead, N.B.-based founder and product developer of PLAEX Building Systems Inc. has created a no-cut, mortarless and reusable system of interconnecting bricks and finish panels — basically Lego for real-life structures. 

Bowers is a carpenter from a family of tradespeople. But after a few years managing multimillion-dollar construction projects out west, he said he could no longer ignore the “insane” amount of waste it generates. 

“If we keep doing this, there ain’t going to be a planet for our kids.” 

Producing PLAEX uses less energy than current recycling methods and very little water, all of which helps lessen its ecological impact, said Bowers.

He first came up with the idea in 2017 and has developed a prototype that is being tested for Canadian Standards Association (CSA) approval and should be ready for purchase orders by August.

Although the product will initially only be certified for use in non-occupied structures — such as retaining walls, flood walls, garages and sheds — eventually he hopes to have it approved for building houses.

When it came to securing a reliable source of plastic waste, Bowers saw another problem he could tackle. He has experience in market gardening and knows how integral plastic is in even the most eco-conscious farm and garden practices.

“A lot of farmers have to bribe their garbage man to get rid of it,” he said. “It’s a problem.”

He reached out to David Wolpin, who runs a farm supply company in Bloomfield, N.B. 

Wolpin supplies farms with plastic for row cover, ground cover, insect netting, greenhouses and irrigation, among other things.

“I said, ‘Well, actually, I can help you set up your whole supply chain,'” said Wolpin. “‘Basically, if you take all the stuff that I sell a few years after I sell it, you’re in business.'”

Raised by “recovering hippies,” Wolpin said the fact that he sells tonnes of plastic every year weighs on his conscience. Most of that plastic is used for between three and 10 years. 

Ultimately, he said, he feels great about supporting local producers — they help reduce carbon emissions from importing food and keep food dollars in the local economy. The plastic he sells helps them extend the local growing season and reduces the use of toxic pesticides by discouraging weed growth and pest damage.

Wolpin is working with Bowers on a Maritime-wide plastic waste collection service for farmers.

Green building expert Keith Robertson of Solterre Design in Halifax thinks PLAEX is innovative in a Canadian context, and likes that it tackles waste in two ways.

First, he said, it diverts plastic from the landfill, where it has been a big problem for municipal waste management. 

Secondly, if the Lego-like, no-cut system can eliminate or even greatly reduce construction waste, “it’s a big plus.”

Rose Murphy

Stay in touch!

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Editor: Andre Mayer | Logo design: Sködt McNalty

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Scientists capture most-detailed radio image of Andromeda galaxy to date – UBC News

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‘Disk of galaxy’ identified as region where new stars are born

Scientists have published a new, detailed radio image of the Andromeda galaxy – the Milky Way’s sister galaxy – which will allow them to identify and study the regions of Andromeda where new stars are born.

Sofia Fatigoni

The study – which is the first to create a radio image of Andromeda at the microwave frequency of 6.6 GHz – was led by University of British Columbia physicist Sofia Fatigoni, with colleagues at Sapienza University of Rome and the Italian National Institute of Astrophysics. It was published online in Astronomy and Astrophysics.

“This image will allow us to study the structure of Andromeda and its content in more detail than has ever been possible,” said Fatigoni, a PhD student in the department of physics and astronomy at UBC. “Understanding the nature of physical processes that take place inside Andromeda allows us to understand what happens in our own galaxy more clearly – as if we were looking at ourselves from the outside.”

Prior to this study, no maps capturing such a large region of the sky around the Andromeda Galaxy had ever been made in the microwave band frequencies between one GHz to 22 GHz. In this range, the galaxy’s emission is very faint, making it hard to see its structure. However, it is only in this frequency range that particular features are visible, so having a map at this particular frequency is crucial to understanding which physical processes are happening inside Andromeda.

In order to observe Andromeda at this frequency, the researchers required a single-dish radio telescope with a large effective area. For the study, the scientists turned to the Sardinia Radio Telescope, a 64-metre fully steerable telescope capable of operating at high radio frequencies, located in Italy.

The Sardinia Radio Telescope, located in Sardinia, Italy. Credit: S. Fatigoni et al (2021)

The Sardinia Radio Telescope, located in Sardinia, Italy. Credit: S. Fatigoni et al (2021)

It took 66 hours of observation and consistent data analysis for the researchers to map the galaxy with high sensitivity.

They were then able to estimate the rate of star formation within Andromeda, and produce a detailed map that highlighted the ‘disk of the galaxy,’ as the region where new stars are born.

“By combining this new image with those previously acquired, we have made significant steps forward in clarifying the nature of Andromeda’s microwave emissions and allowing us to distinguish physical processes that occur in different regions of the galaxy,” said Dr. Elia Battistelli, a professor in the department of physics at Sapienza and coordinator of the study.

“In particular, we were able to determine the fraction of emissions due to thermal processes related to the early stations of new star formation, and the fraction of radio signals attributable to non-thermal mechanisms due to cosmic rays that spiral in the magnetic field present in the interstellar medium,” Fatigoni said.

Final image of the Andromeda galaxy after averaging over the whole bandwidth at 6.6 GHz. Credit: S. Fatigoni et al (2021)

Final image of the Andromeda galaxy after averaging over the whole bandwidth at 6.6 GHz. Credit: S. Fatigoni et al (2021)

For the study, the team also developed and implemented software that allowed them to test new algorithms to identify never-before-examined lower emission sources in the field of view around Andromeda at a frequency of 6.6 GHz.

From the resulting map, researchers were able to identify a catalog of about 100 ‘point sources’ including stars, galaxies and other objects in the background of Andromeda.

Interview language(s): English, Italian

Note for reporters: Sofia Fatigoni is based in Rome, Italy and is available for interviews until 3 p.m. PST.

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To help chart the cosmos, Western space researchers turn to crowd sourcing – CBC.ca

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Western University researchers have tapped the help of hundreds of amateur and professional astronomers in an effort to make sure no meteor is unable to slip by the Earth undetected.

To do that, they’re relying on the observations taken from 450 cameras in 30 different countries manned by “enthusiastic amateur astronomers” made up of professional and citizen scientists.

That data is then sent to Western University as part of what’s called the Global Meteor Network (GMN), headed by Denis Vida.

“So we have a lot of enthusiastic amateur astronomers, citizen scientists and also professionals that build, operate and maintain these cameras,” Vida told CBC’s Chris dela Torre during Afternoon Drive. “And every night they inspect the data set and send their data to a central server here at the University of Western Ontario.”

It’s not just about observing meteors – it’s about tracking what’s left of the ones that make it to the earth’s surface too.

“So we also observe a meteorite dropping fireballs,” said Vida. “They’re quite rare over an area of let’s say the country the size of France or Spain. Could only expect two to three of those fireballs a year that drop more than, let’s say, 300 grams of meteorites on the ground.”

“So because these events are very rare, it is important to observe 24/7.”

Vida explained that when one of their cameras spot one of them, they collect the data and find its location so they can retrieve what’s left for analysis – and analysis needs to happen quickly.  

“There are certain things in them, like some radionuclide to decay very quickly, but those can tell us how old the meteorite is, how long it was after it was ejected from the parent asteroid that it fell on the ground,” he said.

Vida explained that what ends up on the ground are just “several kilograms of materials” by the time they reach the earth’s surface. They aren’t hot either. They cool down on their descent.

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Global push to monitor meteor showers led by Western University – CTV News London

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MIDDLESEX CENTRE, ONT. —
London, Ont.’s Western University is leading a worldwide effort to monitor meteor showers and meteorite falls.

The Global Meteor Network (GMN) includes more than 450 cameras in 23 countries – hosted by amateur and professional astronomers.

The goal of the project, led by Denis Vida, a postdoctoral associate at Western, is to ensure unique or rare space events are not missed.

Vida explained in a statement, “Other astronomers can pool their resources to build a big telescope on top of a mountain where the skies are dark and clear year-round, but meteor astronomers need spatial coverage most of all.”

Meteors can occur anywhere in the world, happen close to earth and often burn up at around 100 km above the surface — so they can only be well observed from within about 300 km and need to be seen by cameras in at least two places to get the exact location.

That’s where the Global Meteor Network comes in.

In March, the network helped locate a rare portion of a meteorite that landed in Winchcombe, England on Feb. 28 and figure out where in space it originated.

“Its role in the recovery and analysis of the Winchcombe meteorite fall is proof positive that GMN works,” said Vida.

The first system to observe meteorites was installed at Western in 2017, and it continues to grow as the cost of meteor cameras has declined.

GMN also publishes the orbits of all observed meteors around the world within 24 hours of observation. The location of cameras and meteor data can be seen here.

The network also hopes to better understand flight patterns and flux capacities of meteorites, and even predict future events.

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