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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

Globe Climate: Canada’s resource reckoning is coming

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Good afternoon, and welcome to Globe Climate, a newsletter about climate change, environment and resources in Canada.

This afternoon, the Alberta government announced that it is restoring a coal mining policy it revoked last spring. At the time, the move provoked a widespread public backlash detailed by The Globe. The original decision, which opened up more than 1.4 million hectares to exploration, was made without public consultation. Premier Jason Kenney previously defended the changes.

Lots more on coal and Canada’s resources industry in this week’s newsletter edition.

Now, let’s catch you up on other news.

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Ecology

‘Incredibly destructive’: Canada’s Prairies to see devastating impact of climate change

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As the climate continues to warm at an alarming rate, experts warn if dramatic steps to mitigate global warming are not taken, the effects in Canada’s Prairie region will be devastating to the country’s agriculture sector.

According to Environment and Climate Change Canada, the country is warming, on average, about double the global rate.

Scientists with the National Oceanic and Atmospheric Administration in the U.S. recently found 2020 was earth’s second-hottest year on record, with the average land and ocean surface temperature across the globe at 0.98 of a degree C above the 20th-century average.

However, the agency found the northern hemisphere saw its hottest year on record, at 1.28 degrees C above the average.

“(In Canada) we are looking at about 6.4C degrees of warming this century, which isn’t much less than one degree per decade, which is just a terrifying rate of warming,” Darrin Qualman, the director of climate crisis policy and action at the National Farmer’s Union said.

Qualman said there is “massive change coming” to Canada’s Prairies, which will be “incredibly destructive.”

“It’s not going too far to say that if we made that happen, parts of the Prairies wouldn’t be farmable anymore,” he said.

According to the federal government, in 2018 Canada’s agriculture and agri-food system generated $143 billion, accounting for 7.4 per cent of the country’s GDP.

The sector employed 2.3 million people in 2018. The majority of the 64.2 million hectares of farmland in Canada is concentrated in the Prairies and in southern Ontario.

The effects of climate change are already being felt on the ground in the Prairies, Qualman said, adding that the NFU has already heard from farmers complaining of “challenging weather.”

“People are sharing pictures of flattened crops and buildings, et cetera, that have been damaged,” he said. “And we’re still at the beginning of this.”

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Ecology

Insect-based dog food aims to cut your pet’s carbon pawprint

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Meat has an enormous carbon footprint, with livestock liable for about 15 per cent of worldwide emissions, as we have beforehand mentioned on this e-newsletter. That is prompted specialists to suggest consuming much less meat for sustainability (and well being) causes.

However what about your pet? One research discovered that the methane and nitrous oxide emissions generated by canine and cat meals within the U.S. alone had been equal to about 64 million tonnes of CO2, or roughly the quantity produced by 13.6 million automobiles. And it might be getting worse, with a development towards feeding pets “human-grade” meat.

That is prompted some pet meals makers to look to lower-carbon protein sources — together with bugs.

Research present that producing insect-based meals requires far much less feed, land and water and generates far fewer greenhouse fuel emissions per kilogram than meats comparable to beef, pork or rooster.

That is one of many causes increasingly more pet meals containing insect protein are hitting the market. Purina, a model owned by multinational Nestlé, launched a line of canine and cat meals containing black soldier fly larvae in Switzerland in November.

In Canada, Montreal-based Wilder Harrier began promoting canine treats made with cricket protein in 2015 and pet food made with black soldier fly larvae in 2019. It plans to broaden to launch a line of insect-based cat treats later this yr and cat meals in 2022 due to “a ton of demand,” mentioned firm co-founder Philippe Poirier.

Wilder Harrier initially labored with animal nutritionists on insect-based merchandise to unravel a unique downside — specifically, the founders’ canines had allergy symptoms to frequent meats utilized in canine meals. Poirier mentioned now about half its prospects hunt down the product due to their pets’ allergy symptoms and about half for environmental causes.

Dr. Cailin Heinze, a U.S.-based veterinary nutritionist licensed by the American School of Veterinary Vitamin, has written concerning the environmental influence of pet meals. She mentioned we’re typically “not as involved as we probably ought to [be]” concerning the environmental footprint of pets.

Alternatively, she famous that the longer-term influence of newer diets, comparable to vegan meals and people containing bugs, hasn’t been nicely examined in comparison with conventional pet meals.

Maria Cattai de Godoy, an assistant professor of animal sciences on the College of Illinois who research novel proteins for pet meals (together with bugs, yeast and plant-based substances), mentioned such substances are rigorously examined to find out their security and diet earlier than being added to pet meals. 

“This can be a very extremely regulated trade,” she mentioned, however admitted it is also evolving.

Relating to bugs, she mentioned constructive information “reveals promise in direction of utilizing them increasingly more in pet meals.” Insect-based proteins have additionally earned the endorsement of the British Veterinary Affiliation, which says some insect-based meals could also be higher for pets than prime steak.

However Godoy famous that there isn’t any one-size-fits-all resolution, and pet homeowners ought to take into consideration the wants of their very own particular person pet and analysis whether or not a specific weight loss plan can be appropriate.

She mentioned that other than the kind of protein, issues like packaging and manufacturing strategies may also make a distinction. For instance, utilizing meat byproducts that may in any other case turn into waste would not drive elevated meat manufacturing the identical approach as utilizing human-grade meat.

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