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95% of existing ocean climates could disappear by 2100 if CO2 emissions continue to climb – Yahoo News Canada

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A new study suggests that, unless CO2 is drastically cut, Earth’s oceans could lose 95 per cent of their existing climates. (Shutterstock/stockphoto-graf – image credit)

Canada is home to three oceans, all of which harbour thousands of fish and animals, on which many Canadians rely. But, with a warming planet, these bodies of water are rapidly changing.

A new study published in the journal Scientific Reports suggests that our oceans’ climates — existing environments with delicately balanced ecosystems — face extreme change under climate-change scenarios.

When trying to predict how our climate will change as a result of increased greenhouse gas emissions, scientists use something called the representative concentration pathway, or RCP. They represent different climate futures under varying levels of greenhouse gas emissions.

In this study, the authors looked at two: RCP 4.5 and RCP 8.5.

Under RCP 4.5 — considered a moderate scenario — emissions peak in 2050, and are then followed by a slowed increase. Under RCP 8.5 — often considered as a “business-as-usual” scenario, and the worst one — emissions peak in 2100 and are then followed by a slowed increase.

Under these scenarios, the authors suggest that 10 to 85 per cent of the surface ocean would see conditions never before seen, or a change in their “climate.”

But under the RCP 4.5 scenario, 35.6 per cent of surface ocean climates may disappear altogether by 2100. Under RCP 8.5, that rises to 95 per cent.

“Previous studies have looked at specific locations and said, ‘Okay, this location’s getting warmer, or this location is getting acidic.’ What we did was, we looked at the whole climate of the global ocean,” said lead author Katie Lotterhos, associate professor of marine and environmental sciences at Northeastern University’s Marine Science Center in Nahant, Maine.

William West/AFP/Getty ImagesWilliam West/AFP/Getty Images

William West/AFP/Getty Images

When they looked at the ocean climates of today compared to 1800, they didn’t see any emergence of “novel” climates or climates that had never been seen before. There were certainly changes, but nothing that was brand new.

But the same couldn’t be said about looking toward the future.

“When you look from today through 2100, depending on the climate-change scenario, and under more extreme climate change scenarios, a higher proportion of the ocean surface is going to experience these novel climates,” Lotterhos said.

And this has dire consequences for the organisms that reside in our vast oceans.

Double whammy

As we produce more CO2, a lot of it is trapped in the atmosphere. However, our oceans actually absorb the majority of it.

A report released by the National Oceanic and Atmospheric Administration (NOAA) this week found that in 2020, the ocean absorbed roughly three billion tonnes more CO2 than what was released, the highest amount since the start of records began in 1982 and roughly 30 per cent higher than the average over the past two decades.

And that changes the ocean’s structure. Not only do our oceans warm, but the greater CO2 absorption also changes pH levels. This change is what is referred to as ocean acidification.

The Nature study examined the level of pH, or acidity, and something that is called a saturation state, which relates to how difficult it is for organisms to make their shells.

They found that under the RCP 4.5 and RCP 8.5 scenarios, the ocean surface will become more acidic with a lower saturation of aragonite, which is a mineral used by corals and other marine organisms to form shells.

Just as we require calcium to make our bones, so do shelled organisms. They get this from seawater, but with ocean acidification, calcium becomes less available and hydrogen becomes more common.

And that presents a double whammy for organisms: it becomes harder to form their shells, and it also becomes more difficult to keep what shells they have from dissolving back into the seawater.

CBCCBC

CBC

Denis Gilbert, a research scientist on climate and ocean physics at the Department of Fisheries and Oceans, and part of the Intergovernmental Panel on Climate Change’s (IPCC) Working Group I, who was not involved in the new study, said that the findings are concerning, though he wouldn’t refer to it as a changing ocean climate, but rather a changing ocean chemistry.

“I was surprised to see that by 2100, there was that much of the ocean that had an entirely different climate, either entirely novel or an entirely extreme [climate],” he said. “But I find the usage of the word climate a bit unfortunate … If the authors had chosen the word chemistry or chemistries, it would better reflect what the paper is actually saying.”

He noted that while they do discuss ocean temperature, the main thing they address is the pH and saturation levels, which is the changing chemistry.

“The bottom line is that they’re concerned with what’s going to happen to the shells of certain animals that calcify with aragonite,” he said.

Winners and losers

However, Lotterhos noted that it doesn’t mean that all shelled organisms — or those that depend on them — are doomed.

“We often talk about winners and losers … in terms of species, but there are a lot of emerging studies that show there are also winners and losers within species,” Lotterhos said. “And that indicates that there’s some genetic variation for which evolution can act on. So there is a lot of hope in the sense that there is genetic variation and a lot of marine species for which evolution can act on and that gives me hope that species will be able to persist in the future.”

And while ocean acidification is rising around the globe, the study suggests that three regions will see the greatest change in novel climates first: the Indo-Pacific, Arctic and Antarctic.

But that’s not to say that Canadians who depend on the oceans for their livelihoods won’t see changes.

Canada’s Changing Climate Report, released by the federal government in 2019, found that the Pacific Northwest, for example, will experience more CO2 and lower pH in the coming decades.

And the Arctic, which is often considered as the pulse of climate change as it warms at twice the rate of the rest of the world — in some places almost four times as much — is experiencing rapid increases in freshwater from melting ice. This, in turn, has reduced the aragonite saturation rate making shelled organisms particularly vulnerable.

But Lotterhos noted that the two different scenarios illustrate that if we make changes and reduce CO2 emissions, it can have a huge impact.

“Humans are slow learners and climate is changing faster than our systems for regulation in management can keep up,” she said. “And so as long as we’re in this pile of bureaucracy, where we can’t adapt our social systems and our management systems to the speed at which climate is changing, it’s going to exacerbate climate change even more so.”

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World's most dangerous bird raised by humans 18000 years ago, study suggests – CTV News

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The earliest bird reared by humans may have been a cassowary — often called the world’s most dangerous bird because of its long, dagger-like toe.

Territorial, aggressive and often compared to a dinosaur in looks, the bird is a surprising candidate for domestication.

However, a new study of more than 1,000 fossilized eggshell fragments, excavated from two rock shelters used by hunter-gatherers in New Guinea, has suggested early humans may have collected the eggs of the large flightless bird before they hatched and then raised the chicks to adulthood. New Guinea is a large island north of Australia. The eastern half of the island is Papua New Guinea, while the western half forms part of Indonesia.

“This behavior that we are seeing is coming thousands of years before domestication of the chicken,” said lead study author Kristina Douglass, an assistant professor of anthropology and African studies at Penn State University.

“And this is not some small fowl, it is a huge, ornery, flightless bird that can eviscerate you,” she said in a news statement.

The researchers said that while a cassowary can be aggressive (a man in Florida was killed by one in 2019), it “imprints” easily — it becomes attached to the first thing it sees after hatching. This means it’s easy to maintain and raise up to adult size.

Today, the cassowary is New Guinea’s largest vertebrate, and its feathers and bones are prized materials for making bodily adornments and ceremonial wear. The bird’s meat is considered a delicacy in New Guinea.

There are three species of cassowary, and they are native to parts of northern Queensland, Australia, and New Guinea. Douglass thought our ancient ancestors most likely reared the smallest species, the dwarf cassowary, that weighs around 20 kilograms (44 pounds).

The fossilized eggshells were carbon-dated as part of the study, and their ages ranged from 18,000 to 6,000 years old.

Humans are believed to have first domesticated chickens no earlier than 9,500 years ago.

NOT FOR SNACKING

To reach their conclusions, the researchers first studied the eggshells of living birds, including turkeys, emus and ostriches.

The insides of the eggshells change as the developing chicks get calcium from the eggshell. Using high-resolution 3D images and inspecting the inside of the eggs, the researchers were able to build a model of what the eggs looked like during different stages of incubation.

The scientists tested their model on modern emu and ostrich eggs before applying it to the fossilized eggshell fragments found in New Guinea. The team found that most of the eggshells found at the sites were all near maturity.

“What we found was that a large majority of the eggshells were harvested during late stages,” Douglass said. “The eggshells look very late; the pattern is not random.”

These late-stage eggshells indicate people living at these two rock shelter sites were harvesting eggs when the cassowary embryos had fully formed limbs, beaks, claws and feathers, the study said.

But were humans purposefully collecting these eggs to allow them to hatch or collecting the eggs to eat? It’s possible they were doing both, Douglass said.

Consuming eggs with fully formed embryos is considered a delicacy in some parts of the world, but Douglass said the research team’s analysis suggested people were hatching the chicks.

“We also looked at burning on the eggshells,” Douglass said in the news release. “There are enough samples of late stage eggshells that do not show burning that we can say they were hatching and not eating them.”

BIG BIRD AS VALUABLE RESEARCH

Less mature eggshells showed more signs of burning — suggesting that when cassowary eggs were consumed they were cooked and eaten when their contents were primarily liquid.

“In the highlands today people raise cassowary chicks to adulthood, in order to collect feathers, and consume or trade the birds. It is possible cassowaries were also highly valued in the past, since they are among the largest vertebrate animals on New Guinea. Raising cassowaries from chicks would provide a readily available source of feathers and meat for an animal that is otherwise challenging to hunt in the wild as an adult,” she explained via email.

However, there is still much the researchers don’t know.

To successfully hatch and raise cassowary chicks, people would need to know where the nests were, know when the eggs were laid and remove them from the nest just before hatching. This is no easy feat as birds don’t nest at the same sites each year. Once a female lays the eggs, male birds take over nest duty and don’t leave for 50 days while incubating the eggs.

“People may have hunted the male and then collected the eggs. Because males don’t leave the nest unattended they also don’t feed much during the incubation period making them more vulnerable to predators,” she said.

The research was published in the peer-reviewed scientific journal PNAS on Monday.

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Atlas V: Rocket launch creates strange lights in UK sky – BBC News

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Simon Woodley

Amateur stargazers in the UK were sent rushing for their cameras by strange cone-shaped lights in the sky created by a US rocket.

Nasa launched the Atlas V, carrying the Landsat 9 satellite, at about 20:00 BST on Monday.

About two hours later it performed a reversing manoeuvre, releasing two glowing clouds of vapour.

Clear skies made for an out-of-this-world view of the stellar spectacle, visible above large parts of UK.

Photographer Simon Woodley “couldn’t believe his eyes” when he snapped the launch from South Shields.

Mr Woodley was out taking photos of the moonrise when he saw the unknown bright light for “three or four minutes”.

“I went through the possibilities of comet or aircraft or even a laser beam. It was only when I got home I found out what it was,” he said.

Education charity UK Astronomy said the light was the rocket’s deorbit burn, created as it fires its engines to commence its re-entry into Earth’s atmosphere before burning up.

Astronomer and science writer Will Gater said the glowing, tear drop-shaped clouds were a result of sunlight scattering off material released into space.

The light seen in the sky from Keighley

Elliott Stone

Elliott Stone, who snapped the rocket from his garden in Keighley, West Yorkshire, thought he was seeing a comet at first.

“I noticed it was travelling the wrong way, so I thought it must have been a plane with its light on,” Mr Stone said.

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What is the Landsat 9 satellite?

The rocket and satellite being launched

Bill Ingalls/NASA/EPA

  • Landsat 9 is part of a satellite array photographing and measuring the Earth’s surface
  • The first Landsat satellite launched in 1972
  • Designed to measure changes on Earth such as deforestation
  • Launched into orbit using an Atlas V rocket from Vandenberg Space Force Base in California

Source: Nasa

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In Whitley Bay, Tyne and Wear, Ian Sproat was left “scrambling” to set up his camera when he saw the light above him.

“I was gobsmacked, I honestly thought it was a meteor or a comet, never did I expect to see the Landsat 9,” he said.

The light next to a lighthouse

Ian Sproat

Mr Sproat only went to the spot near St Mary’s Lighthouse because he thought he might be able to see the northern lights.

“When I got there and was setting up, a ball of light appeared above me,” he said.

He felt “truly blessed to have witnessed this spectacular sight”, he added.

Fellow astronomy enthusiast Freddy Lees snapped a photo of the rocket from Nottingham as it climbed above the tree line shortly after 22:00.

Nottingham

Freddy Lees

The light in Norwich

The NASA Atlas V rocket was launched from California’s Vandenberg Space Force base 20:11 BST.

Visible rocket burns are rare in European skies and more often seen above Florida or California.

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Follow BBC Yorkshire on Facebook, Twitter and Instagram. Send your story ideas to yorkslincs.news@bbc.co.uk.

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This Canadian 'Dark Sky Highway' is a stargazer dream – The Weather Network

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E.C. Manning Provincial Park is one of the most popular provincial parks in British Columbia.

Located in the heart of the Cascade Mountains, its climate and geography have combined to make this park a go-to destination for stargazers across the country.

The park is within a three-hour drive from either the Lower Mainland or the Okanagan, with the closest city being about 45 minutes away. Road trippers can get there using BC Highway 3, also known as the Crowsnest Highway, located along what has become known as the Dark Sky Highway, due to the limited light pollution.


Photo of the night sky captured along B.C.’s Dark Sky Highway. The five bright stars stretched out through the right-hand side of the image are part of the constellation Ursa Major, aka the Big Dipper. (Mia Gordon)

Every year, photographers from around the country come out here to get a good glimpse of the Milky Way and other incredible constellations, and now the Manning Resort and the park are working towards becoming a dark sky designation.

“That means it is a continued commitment to preserve and protect the night and the environment but more specifically the organisms that live in the park that rely on the night to hunt and navigate,” explained Manning Park Communications Manager Emma Schram.

Every year, the resort partners with the Royal Astronomical Society of Canada for an Astronomy Weekend, where visitors can speak with experts, learn how to use a telescope, and even participate in yoga under the stars. This year’s event is taking place October 15-17, and while it is sold out, any time of year is the perfect time to go stargazing in the park.

Learn more about this stargazer’s dream destination in the video above.


Thumbnail image courtesy: Getty Images

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