Dinosaurs survived when CO2 was extremely high. Why can’t humans?

Posted: September 22, 2022 by oldbrew in atmosphere, climate, IPCC, paleo, research, Temperature, volcanos
Tags: ,


Current rates of temperature increase, if accurate, don’t look all that startling despite the odd few hot days. For example, Roy Spencer reports a linear warming trend of +0.13C per decade since 1979. We know previous cooling trends must have occurred over the centuries from the regular advance and retreat of glaciers, to cite one obvious line of evidence. Focussing on CO2 all the time is a bit like looking through the wrong end of the telescope.
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How did plants and animals survive around 200 million years ago when the carbon dioxide concentration went up to 6,000 parts per million?

Paul Olsen, a geologist and paleontologist at Columbia Climate School’s Lamont-Doherty Earth Observatory, walked us through what scientists know about carbon dioxide levels over time, says Phys.org.

Although no one was around to measure the atmosphere’s CO2 concentration millions of years ago, paleoclimatologists can reconstruct past temperature and carbon dioxide levels using ice cores, tree rings, corals, ancient pollen, and sedimentary rocks.

These natural recorders of climate fluctuations can also reveal how various animals and plants thrived or perished during different geological periods.

While studying the Age of Dinosaurs, for example, some researchers dissect leaves that got trapped in sediment layers. “The little holes in the skin of leaves are more common when there are lower carbon dioxide levels,” explained Paul Olsen, a geologist and paleontologist at Columbia Climate School’s Lamont-Doherty Earth Observatory.

Scientists like Olsen have repeatedly found that during several periods of Earth’s history, organisms have experienced radically higher concentrations of carbon dioxide and hotter average temperatures than today. However, that doesn’t mean everything will be fine if we keep heating the planet by burning fossil fuels.

“The problem today is not higher global temperature or carbon dioxide levels alone. The problem is the rate of change,” explained Olsen. “Throughout most of the Earth’s history, carbon dioxide levels have generally changed very slowly. That gave organisms and their ecosystems sufficient time to adapt to climate change through both evolution and migration.”

Climate scientists warn that over the next century, the rate of change will be 10 times faster than any climate pattern that unfolded in the last 65 million years.

Because of today’s rapid rate of warming, up to 14 percent of all plants and animals on land may face extinction in the coming decades, according to a report from the Intergovernmental Panel on Climate Change.

Earth’s climatic ups and downs

During the Cambrian Period, which lasted from 542 million to 485.4 million years ago, some sources estimate that CO2 levels may have been about 20 times higher than today, and temperatures were hotter by 10 degrees Celsius.

Living things didn’t seem to mind the scorching conditions. During this time, the oxygenation of the oceans led to a burst of life known as the “Cambrian explosion.” There was a diverse range of marine creatures like trilobites, including larger ancient predators called Anomalocaris, and slug-shaped animals with shells.

Meanwhile, on land, the earliest plants started taking root around 500 million years ago, possibly enjoying high levels of atmospheric carbon dioxide, said Olsen.

“But the proxies from 500 to 400 million years ago are not that well worked out at this time,” he cautioned. “Most of the data and graphs of carbon dioxide levels in the Earth’s history start at around 350 million years ago.”

During the Ordovician Period (around 488.3 to 443.8 million years ago), the sea level was as much as 220 meters higher than today; the regions north of the tropical belt were under the ocean. Primitive fish, red algae, corals, and a few other marine animals like cephalopods and gastropods were a part of thriving ecosystems—until they were struck by an unprecedented tragedy, which may have been triggered by sudden changes in CO2 levels.

It was Earth’s first major mass extinction. Beginning about 443 million years ago, it wiped out approximately 85 percent of all marine species for up to two million years. The cause remains unknown, but some scientists speculate that it might have been associated with the formation of massive glaciers and a drastic drop in sea levels after the super-continent Gondwana drifted towards the South Pole.

A 2012 study suggested that the first land plants might have caused global temperatures to plummet by absorbing CO2, triggering an ice age.

Conversely, in a 2020 study, Canada-based scientists hypothesized that widespread volcanic eruptions released huge amounts of carbon dioxide that abruptly heated the planet and set off two pulses of mass extinctions within two million years.

Full article here.

Comments
  1. […] Dinosaurs survived when CO2 was extremely high. Why can’t humans? | Tallbloke’s Talkshop (wo… […]

  2. They wrote, Paul Olsen said:
    Climate scientists warn that over the next century, the rate of change will be 10 times faster than any climate pattern that unfolded in the last 65 million years.

    Because of today’s rapid rate of warming, up to 14 percent of all plants and animals on land may face extinction in the coming decades, according to a report from the Intergovernmental Panel on Climate Change.

    We take plants from outside at 400 parts per million CO2 and immediately with a step increase, tripling CO2 in seconds, by placing them in Greenhouses at 1200 parts per million. The cat and the dog go into the higher CO2 environment with the human. The plants thrive and the human and the cat and the dog do just fine.

  3. Paul Olsen, a geologist and paleontologist at Columbia Climate School’s Lamont-Doherty Earth Observatory, walked us through what scientists know about carbon dioxide levels over time,

    Very Clearly, in spite of actual data, they apparently know very little.
    CO2 makes green things grow, more CO2 causes even better growing and production of any product, wood, food, whatever. The dangerous warming from 300 to 400 parts per million, the dangerous warming from adding One Molecule of CO2 to TEN THOUSAND MOLECULES OF ATMOSPHERE HAS NEVER BEEN PROVEN OR EVEN PROPERLY EXPLAINED. When they have no actual reasonable explanation for anything, they pay billions to people with PHDs to sign a “peer reviewed consensus document”. Before CO2 became their champion weapon, millions was spent on climate science, in government and universities. After CO2 became their champion weapon, the spending rapidly increased to Billions a year. The “consensus” had been formed and Billions were made available to support any and all studies and research that confirmed the alarm-ism, and billions were made available to destroy any who disagreed. The bought the Weather Chanel and fired John Coleman, the founder.

  4. Phoenix44 says:

    So many of these Alarmists don’t understand the alarm they are claiming. There’s no “rapid change” that will make species extinct. The global average may be rising but nobody and nothing could notice that. That it’s a bit hot in Europe one year and a bit hot in Australia the next year isn’t going to make any species extinct. Nor will having some days less cold than the long term average and some days a bit warmer than the long term average – nobody and nothing will notice, even if it happened everywhere, every year – which it doesn’t.

    The annual averages in most places vary considerably and vary by more than 1-2 degrees.

  5. Chaswarnertoo says:

    US Navy submarines try to keep CO2 below 10,000 ppm. Of course people can survive these levels. Even if we burnt all available fossil fuels we still would not reach 1000 ppm.

  6. oldbrew says:

    ‘Dinosaurs survived when CO2 was extremely high’

    Compared to what? To now on Earth, maybe. But CO2 on Venus is around 960,000 ppm. That’s where *extremely high* really is.

  7. Gamecock says:

    ‘Although no one was around to measure the atmosphere’s CO2 concentration millions of years ago, paleoclimatologists can reconstruct past temperature and carbon dioxide levels using ice cores, tree rings, corals, ancient pollen, and sedimentary rocks.’

    Gross approximations, masquerading as data. Even today, our measuring capability is quite limited. Yet, they know for millions of years ago.

  8. Graeme No.3 says:

    Gamecock:
    I understood that the original levels were listed by an obsessive German professor who (with his students) spent over 25 years analysing mineral deposits with (known) geological time of origin. Thus the aragonite form of calcium carbonate wasn’t deposited until the CO2 level was greater than 1100 p.p.m. and by 1300 p.p.m. the calcite form was rare.
    I can’t comment on the other crystal forms of mineral compositions involved, but I would point out that sea life proliferated in the Cambrian with CO2 levels thought to be between 4,000 and 7,000 p.p.m. and at the end of the Jurassic when the CO2 was thought to have exceeded 2,500 p.p.m. the Diplodocus, Apatosaurus and the Giraffatitan weren’t extinct from heat stroke.

  9. oldbrew says:

    Global temperature hiatus may not have ended after all, new study suggests
    Friday 23rd September 2022 | Dr David Whitehouse, Science editor (NZW)

    When taken together with a couple of super-strong El Nino events which temporarily drove up global temperature (see graph below), the new findings suggest that the global warming hiatus — clearly evident prior to 2014 — may not have ended yet. If NASA’s satellite data are confirmed, it would suggest that much of the very moderate changes in global temperature this century may have been driven primarily by cleaner air and naturally-occurring El Ninos.

    https://www.netzerowatch.com/global-temperature-hiatus-may-not-have-ended-after-all-new-study-suggests/
    . . .
    Climate obsessives will look the other way as usual. Here’s another one….

    Improved air quality accelerates global warming in recent decades
    Researchers call for greater efforts to fight global warming
    Date: September 21, 2022

    Reduction in aerosol-induced cooling increases warming due to CO2 since 2000 by up to 50 per cent

    This has also reduced the cooling effect of aerosols. Compared to the year 2000, it has led to an increase in the warming effect that is up to 50 per cent of the one by CO2 increases in the same period.

    https://www.sciencedaily.com/releases/2022/09/220921113140.htm
    . . .
    What they think their ‘fight’ should consist of is not clear. Have they even heard of natural cloud albedo variation?

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