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Seen from space: the volcanic eruption that likely triggered Indonesia’s devastating tsunami

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Krakatau volcanic eruption

A volcanic cloud from the eruption of Anak Krakatau in Indonesia on December 22, 2018 is seen in this animation of satellite images acquired by the Himawari-8 satellite. Two distinct volcanic pulses are evident. (After clicking on the screenshot above, click “play” in the upper left corner of the page that launches. If the animation does not run, refresh the page. Source: RAMMB/CIRA SLIDER)

In Indonesia, they call it “Anak Krakatoa, meaning “child of Krakatoa.”

It’s a volcano that rose from the sea in the 1920s decades after one of the most deadly volcanic cataclysms in recorded history killed tens of thousands of people and all but obliterated the island of Krakatoa, east of Java.

Now, Anak Krakatau has itself brought great misery to Indonesia, with an eruption that apparently triggered an underwater landslide, which in turn sent a tsunami racing toward the western tip of the island of Java. A wall of water roared ashore, catching residents and vacationers completely unawares. As I’m writing this on Christmas Eve, more than 370 people have perished, and more than a hundred still are missing.

When Anak Krakatau erupted on December 22, Japan’s Himawari-8 weather satellite was watching from geostationary orbit, 22,239 miles overhead. Click on the screenshot above to watch what the satellite saw.

The animation consists of “GeoColor” imagery acquired in different parts of the electromagnetic spectrum at 10-minute intervals starting at 11:00 UTC. A first pulse of ash is visible at about 13:40, and then a second one at 15:20. As the animation continues, dawn breaks and a plume of ash and steam can still be seen amidst a cloudy atmosphere.

Here’s what the eruption looked like in the infrared part of the electromagnetic spectrum:

Volcanic eruption of Anak Krakatau as seen in the infrared by Himawari-8

An infrared view acquired by the Himawari-8 satellite shows the volcanic eruption of Anak Krakatau. (Source: Cooperative Institute for Meteorological Satellite Studies)

The infrared data in this animation reveal cloud-top temperatures of  -80º Celsius or colder. This suggests the plume billowed up to nearly 10 miles high in the atmosphere, according to the Cooperative Institute for Meteorological Satellite Studies.

As the ash soared high, the volcano’s south flank collapsed. For a visual explanation of how that probably led to the tsunami, check out this video from Geoscience Australia:

It wasn’t as if Anak Krakatau had been dormant prior to the eruption. For months, the volcano had been spewing superheated ash into the sky and lava into the Sunda Strait between Java and Sumatra, Indonesia’s two largest islands. In July, the volcano even threw truck-sized lava bombs skyward.

But the tsunami crashed ashore without warning. News reports say Indonesia’s tsunami warning system had not been operating properly.

But even if the system had been operable, it might not have made a difference. Speaking of the tsunami in an interview on National Public Radio, University of Alberta geoscientist Stephen Johnston noted that were “no sensors in the way that would have detected it.” And even if sensors had been present, the tsunami was triggered so close to shore that “there would have been no chance for any significant warning to have got to these people.”

27th May 1883: Clouds pouring from the volcano on Krakatoa (aka Krakatau or Rakata) in south western Indonesia during the early stages of the eruption which eventually destroyed most of the island. Royal Society Report on Krakatoa Eruption - pub. 1888 Lithograph - Parker & Coward (Photo by Hulton Archive/Getty Images)

Clouds pour from the Krakatoa volcano during May of 1883, as depicted in a lithograph originally published in 1888 by a Royal Society Report on the eruption. This was an early stage in an event that led to one of the most devastating volcanic cataclysms on record. (Source: Wikimedia Commons)

Death and destruction from volcanic eruptions are nothing new in this part of the world. In fact, Krakatoa — Anak Krakatau’s ‘parent’ — exploded far more massively in August of 1883. The explosion, following more than a month of activity, rocketed billions of tons of pumice up to 50 miles into the sky; ten days later, dust fell 3,000 miles away.

The explosion also caused the entire 2,600-foot-high volcanic cone to collapse, obliterating most of the island and triggering tsunami waves that towered up to 130 feet high. An estimated 36,000 people perished, swallowed up by the mountains of onrushing water.

A photograph taken in 1928 shows Anak Krakatau, or "Child of Krakatoa," which rose up after Krakatoa island was destroyed following the massive eruption in 1883. (Source: Tropenmuseum, via Wikimedia Commons)

Anak Krakatau, or “Child of Krakatoa,” spews ash during the 1920s. The volcano rose up after Krakatoa island was destroyed following the massive eruption in 1883. (Source: Tropenmuseum, via Wikimedia Commons)

It took more than 40 years for Anak Krakatau to rise up from the undersea remains of Krakatoa. You can see it erupting in 1928 in the photograph above.

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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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Ecology

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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Ecology

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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