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In the Blink of an Eye, We’re Turning Back the Climatic Clock by 50 Million Years

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This animation based on computer modeling shows what climatic conditions will look like out to the year 2280 if we emissions of greenhouse gases are not restrained. The color coding shows how future conditions would compare to climates of the past. (Source: "Pliocene and Eocene provide best analogs for near-future climates," K. D. Burke et al, Proceedings of the National Academy of Sciences Dec 2018, 201809600; DOI: 10.1073/pnas.1809600115)

This animation depicts climatic conditions out to 2280 assuming emissions of greenhouse gases are not restrained. The color coding shows how future conditions would compare to past climates, with lighter orange corresponding to the Pliocene Epoch about 3 million years ago, and darker orange to the Eocene about 50 million years ago. Dark red indicates future climatic conditions with no past analog. (Source: “Pliocene and Eocene provide best analogs for near-future climates,” K. D. Burke et al, Proceedings of the National Academy of Sciences Dec 2018, 2018)

Absent serious action on climate change, we’ll continue careening toward a climatic cliff. And modern civilization will be hard-pressed to survive the plunge.

This is the essential take-away from new research probing Earth’s climatic past to yield insights into our future. The research finds that if our emissions of carbon dioxide and other greenhouse gases continue unabated, Earth’s climate will warm by the year 2150 to levels not seen since the largely ice-free Eocene Epoch about 50 million years ago.

That may seem like a long time on a human timescale. But consider that the research shows we’re currently on course to reversing 50 million years of cooling in just a couple of centuries. That may be so rapid that it will outpace our ability to adapt our agricultural and other modern life support systems.

Thanks to our emissions of greenhouse gases, “the Earth system is well along on a trajectory to a climate state different from any experienced in our history of agricultural civilizations,” write Kevin Burke and his co-authors in a paper published in the Proceedings of the National Academy of Sciences.

Here’s why that’s troubling: Modern human civilizations, made possible by agriculture, have thrived in what scientists term “a safe operating space,” meaning a stable, relatively benign climate. But now, staying within that safe space seems to be “increasingly unlikely,” the researchers write.

“If we think about the future in terms of the past, where we are going is uncharted territory for human society,” says the study’s lead author, Kevin Burke, in a press release. Burke led the research while he was a graduate student in the lab of paleoecologist John “Jack” Williams of the University of Wisconsin-Madison.

“We are moving toward very dramatic changes over an extremely rapid time frame, reversing a planetary cooling trend in a matter of centuries,” Burke says.

Temperature trends for the past 65 million years and potential geohistorical analogs for future climates. Red arrows show six geohistorical states of the climate system: Paleocene, Miocene, Oligocene, TK, TK and TK. A time series showing global mean annual temperatures is also shown. Major patterns include a long-term cooling trend, periodic fluctuations driven by changes in the Earth’s orbit, and recent and projected warming trends. Temperature anomalies are relative to 1961–1990 global means. (Source: TKTK

Temperature trends for the past 65 million years and potential past analogs for future climates. Red arrows show  “geohistorical” states of the climate system. From the left, these are the early Eocene Epoch; the mid-Pliocene; the last interglacial, or LIG; the mid-Holocene; the pre-industrial period; the historical period; and projections for the future (at extreme right). The time series shows how global mean annual temperatures departed from the 1961 to 1990 mean. Major patterns include a 50-million-year cooling trend beginning in the Eocene, periodic fluctuations driven by changes in the Earth’s orbit, the recent warming caused by human activities, and projected warming. (Source: “Pliocene and Eocene provide best analogs for near-future climates,” K. D. Burke et al, Proceedings of the National Academy of Sciences Dec 2018, 2018)

To conduct the research, Burke and his colleagues compared climatic conditions of several periods in geologic history with computer model projections of the future. These projections assumed different greenhouse gas emission scenarios.

One sobering finding was that we are already headed toward a climatic state like that of the mid-Pliocene Epoch about 3 million years ago even if we do manage to reduce our emissions of greenhouse gases. In fact, thanks to burning of fossil fuels and other human activities, carbon dioxide concentrations in the atmosphere are already at Pliocene levels: more than 400 parts per million. We just don’t have a Pliocene-like climate yet because most of the planet’s surface is covered in oceans — and all that water takes time to warm up.

The research shows that if we undertake moderate emissions reductions, we’ll stabilize at Pliocene-like temperatures by 2040. During the Pliocene, temperatures were between 3.2 and 6.5 degrees Fahrenheit (1.8 to 3.6 degrees Celsius) warmer than they are today.

At their peak, sea level during the Pliocene stood 72 feet (22 meters) higher than today. Luckily, inertia in the climate system means that it would take a few centuries before sea level would come up to that level again. (Looking at past climates, scientists have documented maximum rates of sea level rise of three to five meters per century.)

Even so, Pliocene-like temperatures should bring a host of climate impacts that will prove challenging for modern societies to adapt to. And over time, we’ll have to deal with that Pliocene-like sea level rise.

“There is a very good relationship between sea level and temperature on the planet,” says James White, a paleoclimatologist at the University of Colorado who was not involved in the current research. “If you warm up air, and you warm up water, you melt ice. And when land ice melts and goes into the ocean, you raise sea level.”

The 20 meters of sea level rise that correspond to a Pliocene-like climate “is enormous,” White says. It would submerge coastal cities around the globe which are currently home to many tens of millions of human beings.

The silver lining is that by reducing carbon emissions, we’d at least stabilize climatically without things getting even more challenging. But if we don’t reduce our emissions, the planet will continue to warm — quite dramatically.

By the year 2150, Earth’s average temperature would rise by a staggering 23 degrees Fahrenheit (13 degrees Celsius) above current conditions, taking them to Eocene-like levels. During that geologic epoch, there was no permanent ice on the planet, and sea level is estimated to have been at least 100 meters higher than today.

If we follow this path, the rapid change we’d trigger would be without precedent during the entire Cenozoic Era, the age of mammals, which began about 65 million years ago when the dinosaurs went extinct.

“What the planet’s going to do is very predictable,” White observes. Basic physics plus research on past climatic states provides confidence that “temperatures will rise, sea level will go up, and storms will get worse. It’s all very predictable. What’s not is how we will respond.”

I don’t know about you, but I’d prefer to respond in a way that would leave us in the Pliocene, not the Eocene.

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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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