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Earth Science

Ocean Acidification Can Cause Mass Extinctions, Fossils Reveal (theguardian.com) 90

After analyzing fossil records from 66 million years ago, researchers determined that ocean acidification can cause the mass extinction of marine life. The Guardian reports: The researchers analysed small seashells in sediment laid down shortly after a giant meteorite hit the Earth, wiping out the dinosaurs and three-quarters of marine species. Chemical analysis of the shells showed a sharp drop in the pH of the ocean in the century to the millennium after the strike. This spike demonstrated it was the meteorite impact that made the ocean more acidic, effectively dissolving the chalky shells of many species. Large-scale volcanic activity was also considered a possible culprit, but this occurred over a much longer period.

The oceans acidified because the meteorite impact vaporized rocks containing sulphates and carbonates, causing sulphuric acid and carbonic acid to rain down. The mass die-off of plants on land after the strike also increased CO2 in the atmosphere. The researchers found that the pH dropped by 0.25 pH units in the 100-1,000 years after the strike. It is possible that there was an even bigger drop in pH in the decade or two after the strike and the scientists are examining other sediments in even finer detail. [Michael Henehan at the GFZ German research center for geosciences in Potsdam said]: âoeIf 0.25 was enough to precipitate a mass extinction, we should be worried.â Researchers estimate that the pH of the ocean will drop by 0.4 pH units by the end of this century if carbon emissions are not stopped, or by 0.15 units if global temperature rise is limited to 2C. Henehan said: âoeWe may think of [acidification] as something to worry about for our grandchildren. But if it truly does get to the same acidification as at the [meteorite strike] boundary, then you are talking about effects that will last for the lifetime of our species. It was hundreds of thousands of years before carbon cycling returned to normal.â
The research has been published in the journal Proceedings of the National Academy of Sciences.
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Ocean Acidification Can Cause Mass Extinctions, Fossils Reveal

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  • I mean is that a surprise? Next study: pumping carbon monoxide in a room will cause mass extinction of the inhabitants of the room.

    • Life, uh, finds a way.

      cor, a Novel Carbon Monoxide Resistance Gene, Is Essential for Mycobacterium tuberculosis Pathogenesis [asm.org]

      Tuberculosis, caused by Mycobacterium tuberculosis, remains a devastating human infectious disease, causing two million deaths annually. We previously demonstrated that M. tuberculosis induces an enzyme, heme oxygenase (HO1), that produces carbon monoxide (CO) gas and that M. tuberculosis adapts its transcriptome during CO exposure. We now demonstrate that M. tuberculosis carries a novel resistance gene to combat CO toxicity. We screened an M. tuberculosis transposon library for CO-susceptible mutants and found that disruption of Rv1829 (carbon monoxide resistance, Cor) leads to marked CO sensitivity. Heterologous expression of Cor in Escherichia coli rescued it from CO toxicity. Importantly, the virulence of the cor mutant is attenuated in a mouse model of tuberculosis. Thus, Cor is necessary and sufficient to protect bacteria from host-derived CO. Taken together, this represents the first report of a role for HO1-derived CO in controlling infection of an intracellular pathogen and the first identification of a CO resistance gene in a pathogenic organism.

      Plus, I think you're being a bit fast and loose when you define mass extinction.

      • Life, uh, finds a way.

        Movie quotes aren't science. And your science only shows that a small subset of life will find a way through the current crisis, which was never at dispute. Nobody thinks human activity will end all life on Earth, or at least nobody whose opinion is worth listening to. The question is whether it's going to end human-like life on Earth.

        • And your science only shows that a small subset of life will find a way through the current crisis, which was never at dispute.

          It's very much disputable. After all, these things [google.com] evolved during a period in which CO2 levels where many times what they are today. Which kind of throws a wrench in the "dissolved shells" notion.

          The question is whether it's going to end human-like life on Earth.

          There are many questions, and that one might not even be among them.

          • Yes, it is possible for animals to evolve shells in different environments. The problem is that the currently existing animals evolved to survive in the environment of recent past, when CO2 levels were NOT as high as they are today. Building their shells requires the pH level to be within a certain range, and we're moving out of that range. The giant ammonites are extinct, and their living relatives don't have shells...

    • by e3m4n ( 947977 )

      exactly! its no new science that pH affects the nutrient uptake of various plant life, which also, in turn, affects oxygenation of the water. It also affects fish shedding scales and other abnormalities.

      And I thought Price Line is the ones who had Captain Obvious.

    • As long as we're nit-picking, a more accurate headline would be, "Scientists Find Evidence to Support Hypothesis that Ocean Acidification Caused Mass Dieoff." It's only one more piece of evidence in a puzzle that scientists have been trying to solve for over a century.
      • We have known this for many years that the sulphur trioxide caused acid rain that acidified the top level of the oceans and caused mass die offs. Why this is being brought up again now is just to link it to climate change.

    • Comment removed based on user account deletion
      • as there's a large number of people who want desperately to believe there's a single cause for why Dinosaurs no longer dominate the land.

        Dinosaurs no longer dominate the land? Well that would explain why there are about two dinosaurs species for each current mammal species?

        Cue signature, which I haven't seen sufficient reason to change for years.

  • whale, polar bear, small islands, save the ocean, save the climate...
    Whats next? Who do we pay and what new tax is needed?
    To get help going?
    • A tip for those of you who are tax adverse: You can save a lot of taxes by wrapping your lips around a tailpipe.
  • by AbRASiON ( 589899 ) * on Monday October 21, 2019 @11:58PM (#59333728) Journal

    https://en.wikipedia.org/wiki/... [wikipedia.org]

    I mean it's all over fairly soonish, enjoy it while you can.

    • by DogDude ( 805747 )
      Jesus, that's the most depressing Wikipedia article I've ever seen.

      I'm in school and let me tell you, studying biology is depressing as hell. It seems that most of the current studies revolve around how x is being impacted by climate change. It's pretty grim.
      • I was born in the 1980s. The world has changed and it is actually depressing. So, your education is teaching you correctly, though perhaps they should teach you the bright side of mass extinction instead.
      • Maybe that's where the grants are...

        Speaking of depressing, it's not just biology. There's an ever-increasing load of bad news coming our way almost daily. First it was acid rain going to do us in, then a new ice age, the CO2, smog, NOx, particulates, microplastics and PFAS deposits, runaway weather patterns, and now ocean acidity. All real problems, but all presented as the next Great Disaster going to happen. Maybe it's just my take on what I read and see around me, but it seems there's a bit of a s
        • by DogDude ( 805747 )
          A few like Extinction Rebellion* and Thunberg's followers are organising into what look like weird and rather loud doomsday cults

          That's not true. The facts are really, really bad, and people like Thunberg are talking about reality. We're already dealing with the results of climate change, and people are dying as a result. Things are going to get much worse in the next few decades. That's not hyperbole. Every scientist that I know is equally as concerned (and generally hopeless about the situation).
        • When I was in college, a PoliSci professor was wringing his hands over the depleting global reserves of mercury (a metal now banned for most uses) in the disappearing scarce resources trope.

          He was chagrinned when I pointed out we didn't particularly need new reserves exploration with already a hundred years reserves then, much less now with mercury programmed out of most industrial and home uses. But now he is a distinguished Johns Hopkins PoliSCi emeritus prof for his insights ...
        • by dryeo ( 100693 )

          Here in Canada, we just had a federal election where climate change was perhaps the biggest issue with the other being affordability even with the record low unemployment.

          • Here in Canada, we just had a federal election where climate change was perhaps the biggest issue with the other being affordability even with the record low unemployment.

            Being in Canada, I assume the candidate in favor of it won?

            • by dryeo ( 100693 )

              Basically. It's more complex as it is a Parliamentary system and the winner will need help from those even more in favour to govern as they don't have a majority. The party against actually got the most votes by sweeping the oil producing areas, about 32% vs 31% for the winner with the other third split between the other three parties who are more in favour of climate action (the extreme right wingers who were totally against got about 1-2%). Even the Bloc Quebecois, who are mostly about Quebec are adamant

  • For example, consider offshore from Monterey Bay [noaa.gov]. We see the natural swing in pH tends to be more than 10 times the "climate induced" trend over the last 20 years. pH is also logarithmic, meaning it's going to take an order of magnitude MORE CO2 in the water to even approach what happens naturally.

    But "ocean acidification" makes a great scare-mongering headline, doesn't it?

    • For example, consider offshore from Monterey Bay.

      From your fine link:

      Ocean acidification describes a decrease in ocean pH levels caused by an increase in dissolved CO2. The natural process of upwelling that occurs along the central California coast already results in a high amount of dissolved CO2 in this area because upwelling brings CO2-rich waters from the deep ocean to the shelf environment. Human-caused CO2 adds to the overall level of dissolved CO2 in these waters and could exacerbate ocean acidification in the offshore environment (Doney et al. 201

      • We are? Have we swung the limits? From the data I linked, the peaks happened quite a bit ago - and even though the CO2 in the atmosphere continues to grow, the pH limits haven't been pushed.
  • What about plasticification, do we know yet?

  • Normal range for sea water pH is 7.7-8.2, varying day to day and depending on the time of day, measured in one place: https://web.archive.org/web/20... [archive.org] The min/max range measured across different locations will be greater. It is also worth noting that sea creatures evolved shells back in the Cambrian era, some 500M years ago - when atmospheric CO2 levels were 10-20x higher than they are today. So it seems we need less alarmism and hyperbole and more science.
    • by DogDude ( 805747 )
      A. You're linking to data from who knows where. It's not a scientific paper. It's ten years old. It's got a sample size of one. It's not relevant.

      B. The chart showing the most recent pH levels, if it were correct or relevant, shows a significant drop in pH over the past decade.

      C. A range in levels doesn't mean that the mean can't change over time. In this case, mean ocean pH is rapidly changing over time.
    • This is such a ridiculous argument. Just because some animals lived in some environment 500M years ago doesn't mean that unrelated currently living animals who did NOT evolve in that environment would be able to survive in the same conditions! The animals that exist now are adapted to conditions that have existed in the relatively recent past.

  • Fake news. The Earth is about 6,000 years old at most.
  • Many people don't have the thinnest understanding of redox chemistry. Yes, carbon dioxide lowers water pH, because it pulls oxygen out of the water by requiring an OH- ion to dissolve. Temperature is critical to the behaviour of carbonic acid, it is somewhat unusual amongst acids because it is a gas, and no reaction occurs EVER, anywhere, without dissolution, such other types of reactions can only be caused by radioactivity or quantum effects, they don't affect ionic bonding directly. Hot liquids dissolve l
  • since the 70s 60% of species have gone extinct.
    were only 17% away from eclipsing the extinctions occurring at the end of the cretaceous period.

    all that in just 40 odd years, We need to stop talking like there might be a problem
    and dealing with the problem now. Commissioning new reports that just gathers more
    evidence of what we already know. We are in the midst of the 6th Mass extinction and up to 200
    species go extinct each day.

    I dont understand why the tech industry has such a hard time dealing with scienti

  • The facts are overwhelming that CO2/SO* did a lot of damage in the past and took centuries to correct itself. So, the easiest thing to stop is the SO*, which comes from coal plants, along with dirty diesel/gasoline. As of 2005, The worst emitter of this is China, with ~28%. [atmos-chem-phys.net]
    Next up would be America/Canada with about 12% of the emissions, with Western/Central Europe at ~9%.
    Based on the data in that paper, CHina's emissions has almost certainly gone up, with America/Canada's, and Europe's continuing their do
    • During the Great Recession when people were talking about jobs programs I thought they should be building nuclear plants. Sure, the waste is an issue, but I don't think renewables alone are likely to provide the excess power needed to do any active mitigation. Ironically, China seems like the sort of regime where they could do large scale nuclear rollout alongside energy intensive carbon capture on a societal level, but environmentalism isn't a priority for them.
    • by Nikkos ( 544004 )

      You can turn America and Europe Off COMPLETELY and still not do anything to affect the environment at this point. China and India will still poison the planet.

      For the most part, America and Europe have 'solved' their problems as well as they're likely to do until non-fossil fuel energy sources are competitive and viable. And even when that switch finally occurs, it's not going to have a global impact.

      China and India are completely opposite. They're pumping out poison and pollution of every type, dumpin

    • Yet more lies from WindBourne.
      China's SO2 emissions peaked in 2006 and decreased in every year since. Is that why you chose 2005 for your data?
      Why bother linking to data 15 years out of date? A quick glance at something more recent [euronews.com] tells us that.

      The analysis found that India was the top emitter of SO2 in 2018 and made up 15% of global emissions. The country recently surpassed Russia and China.

      and that

      China and the United States, meanwhile, have reduced emissions rapidly by switching to clean energy sources, Greenpeace said, though both are still within the top ten country emitters.

      And here we see the facts [nasa.gov]

      Although China and India remain the world’s largest consumers of coal, the new research found that China’s sulfur dioxide emissions fell by 75 percent since 2007, while India’s emissions increased by 50 percent. The results suggest that India is becoming, if it is not already, the world’s top sulfur dioxide emitter.

      You really are just a constant liar about anything to do with China aren't you WindBourne.

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