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Did Huge Volcanic Eruptions Help Kill Off The Dinosaurs?

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A large series of volcanic eruptions created India’s Deccan Plateau right around the same time dinosaurs were going extinct. (Planet Labs, Inc/Wikimedia Commons)

Nearly 66 million years ago, most living things on Earth died. Most researchers agree that the prime culprit was an asteroid that struck Mexico’s Yucatan Peninsula, leading to the mass extinction that took out most of the dinosaurs. But in a new research published Thursday, two independent research groups are making the case that enormous volcanic eruptions in India likely contributed to the demise of life, too.

The findings shed light on not only one of the most famous events in Earth’s history, but also the potential consequences of current environmental change, the researchers say.

“Understanding past extinction events — their causes, and eventual climatic and biotic recoveries — is crucial … when trying to wrap our heads around the many possible outcomes of our current trajectory towards disastrous climate change, ecosystem destruction and potential mass extinction,” Blair Schoene, a geologist at Princeton University in New Jersey, who led one of two new studies, said in a statement.

Death Debate

Geologic evidence uncovered in the ’80s and ’90s led researchers to conclude that a giant asteroid’s collision with Earth caused the extinction event. That setoff a worldwide hunt for the impact site. Amd geologists announced they’d finally discovered the Chicxulub crater in 1991.

“Despite this evidence, the impactor hypothesis has met with some skepticism because many extinction events roughly coincide with the [explosion] of enormous volumes of volcanic rock onto and into Earth’s crust,” explains Seth Burgess, a volcanologist with the U.S. Geological Survey in Menlo Park, California, who was not involved in the research, in a related perspective piece.

That lingering debate has led other scientists to study India’s Deccan plateau, an enormous landmass extending east and south of Mumbai, to create a precise timeline of the volcanic eruptions. For the latest analysis, Schoene and a research team studied uranium and lead isotopes — commonly used to date rocks — that they found in zircon mineral crystals buried beneath the lava flows. It revealed four high-volume eruptions that happened between 66.4 and 65.6 million years ago. The data show that the second of these eruptions likely began tens of thousands of years before the mass extinction event, the researchers report in the journal Science.

Unending Eruption

In a second study also out Thursday in Science, another team used a different technique to corroborate the finding. Here, the researchers assessed argon isotopes to date the eruption of lavas in the area. Their analysis also showed the eruptions began thousands of years before the mass extinction. However, the investigation revealed a more or less continuous eruption that lasted for about a million years. Although the finding contrasts with the punctuated eruptions Schoene and team discovered, both studies agree the Deccan eruptions likely played a role in the mass extinction event.

Given the timing of the eruption events and the meteor impact, it’s possible the two triggers delivered a double-whammy deathblow.

“Both of our datasets suggest a coincidence between the onset of Deccan eruptions and Late Cretaceous climate change, which has been attributed to the weakening of Late Cretaceous ecosystems, possibly making them more susceptible to the effects from the meteor impact,” Courtney Sprain, a geoscientist who led the second study while at the University of California Berkeley, said in a statement.

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Ecology

Today’s letters: ‘Visionary’ plans don’t always work in Ottawa

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The opinion piece written by Tobi Nussbaum, CEO of the NCC, declares that a “bold, visionary transit plan” would showcase the capital.

As a long-term resident of Ottawa, I’ve had it with visionary plans. In the 1950s, the streetcars serving Ottawa so well were sent to the scrapyards. In the early ’60s, Queensway construction bulldozed established neighbourhoods and ripped the city apart. Later in the decade, the downtown railway station, which could have formed the hub of a commuter network, was relocated to the suburbs. These actions, in the name of “progress,” were undertaken with the “vision” to make Ottawa a car-reliant city.

Now we have an LRT, built just in time for most people to realize that they do not have to go downtown as they can work from home.

Current thinking is pushing a new “link” between Ottawa and Gatineau, with yet more expensive and disruptive infrastructure projects being touted, including a tramway or another tunnel under the downtown core.

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That was then: Biggest earthquake since 1653 rocked Ottawa in 1925

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A regular weekly look-back at some offbeat or interesting stories that have appeared in the Ottawa Citizen over its 175-year history. Today: The big one hits.

The Ottawa Senators were playing a Saturday night game against the Montreal Canadiens at the Auditorium, the score tied 0-0 halfway through the second period. Sens’ rookie Ed Gorman and the Habs’ Billy Boucher had just served penalties for a dustup when the building began to make “ominous creaking sounds.” A window crashed to the ground.

Nearby, at Lisgar Collegiate, all eyes were on teenager Roxie Carrier, in the role of Donna Cyrilla in the musical comedy El Bandido. She had the stage to herself and was singing “Sometime” when the building rocked, the spotlight went out, and someone in the audience yelled “Fire!”

At a home on Carey Avenue, one woman’s normally relaxed cat suddenly arched its back, rushed around the room two or three times, spitting angrily, and climbed up the front-window curtains.

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Ottawa delays small nuclear reactor plan as critics decry push for new reactors

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TORONTO — Canadians will have to wait a little while longer to see the federal government’s plan for the development of small nuclear reactors, seen by proponents as critical to the country’s fight against global warming.

Speaking at the opening of a two-day virtual international conference on Wednesday, the parliamentary secretary to the minister of natural resources said the plan will lay out key actions regarding the reactors. Its launch, Paul Lefebvre said, would come in the next few weeks.

“We’re still putting the finishing touches on it,” Lefebvre said. “The action plan is too important to be rushed.”

Small modular reactors — SMRs — are smaller in size and energy output than traditional nuclear power units, and more flexible in their deployment. While conventional reactors produce around 800 megawatts of power, SMRs can deliver up to 300 megawatts.

Proponents consider them ideal as both part of the regular electricity grid as well as for use in remote locations, including industrial sites and isolated northern communities. They could also play a role in the production of hydrogen and local heating.

“SMRs will allow us to take a bold step of meeting our goal of net-zero (emissions) by 2050 while creating good, middle class jobs and strengthening our competitive advantage,” said Lefebvre.

Natural Resources Minister Seamus O’Regan had been scheduled to speak at the conference but did not due to a family emergency.

Industry critics were quick to pounce on the government’s expected SMR announcement. They called on Ottawa to halt its plans to fund the experimental technology.

While nuclear power generation produces no greenhouse gas emissions, a major problem facing the industry is its growing mound of radioactive waste. This week, the government embarked on a round of consultations about what do with the dangerous material.

Dozens of groups, including the NDP, Bloc Quebecois, Green Party and some Indigenous organizations, oppose the plan for developing small modular reactors. They want the government to fight climate change by investing more in renewable energy and energy efficiency.

“We have options that are cheaper and safer and will be available quicker,” Richard Cannings, the NDP natural resources critic, said in a statement.

Lefebvre, however, said the global market for SMRs is expected to be worth between $150 billion and $300 billion a year by 2040. As one of the world’s largest producers of uranium, Canada has to be part of the wave both for economic and environmental reasons, he said.

“There’s a growing demand for smaller, simpler and affordable nuclear technology energy,” Lefebvre said.

Joe McBrearty, head of Canadian Nuclear Laboratories, told the conference the company had signed a host agreement this week with Ottawa-based Global First Power for a demonstration SMR at its Chalk River campus in eastern Ontario. A demonstration reactor will allow for the assessment of the technology’s overall viability, he said.

“When talking about deploying a new technology like an SMR, building a demonstration unit is vital to the success of that process,” McBrearty said. “Most importantly, it allows the public to see the reactor, to kick the tires so to speak, and to have confidence in the safety of its operation.”

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