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Earth

Last Time CO2 Levels Were This High, There Were Trees at the South Pole (theguardian.com) 408

An anonymous reader shares a report: Trees growing near the South Pole, sea levels 20 metres higher than now, and global temperatures 3C-4C warmer. That is the world scientists are uncovering as they look back in time to when the planet last had as much carbon dioxide in the atmosphere as it does today. Using sedimentary records and plant fossils, researchers have found that temperatures near the South Pole were about 20C higher than now in the Pliocene epoch, from 5.3m to 2.6m years ago. Many scientists use sophisticated computer models to predict the impacts of human-caused climate change, but looking back in time for real-world examples can give new insights. The Pliocene was a "proper analogy" and offered important lessons about the road ahead, said Martin Siegert, a geophysicist and climate-change scientist at Imperial College London. "The headline news is the temperatures are 3-4C higher and sea levels are 15-20 metres higher than they are today. The indication is that there is no Greenland ice sheet any more, no West Antarctic ice sheet and big chunks of East Antarctic [ice sheet] taken," he said.
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Last Time CO2 Levels Were This High, There Were Trees at the South Pole

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  • Born too late to conquer the Americas.

    BTW, what round for dinosaur?

  • This is yet another demonstration that CO2 by itself is not causing much warming. There are other factors involved, including solar output...

    That's the worst thing about the whole scare-mongering over global warming, the misleading people into believing such a simplistic picture of a complex system. It lets many believe they are doing something to help, when in fact they are doing nothing or possibly making things worse.

    • Thermodynamics still applies to complex systems. If you raise the thermal equilibrium of a system, simple or complex (however you define either term), there will be substantial effects. The only issue in a system with a lot of inputs and variables is just how those changes propagate and how they may effect existing cycles and create new feedback loops and cycles. But using the word "complex" does not make the entire premise disappear.

    • Exactly. Correlation doesn't necessarily imply causation. If CO2 was this high with warmer temps before and colder temps now, it seems to actually imply the correlation is pretty weak.
    • Re: (Score:2, Interesting)

      by caladine ( 1290184 )

      This is yet another demonstration that CO2 by itself is not causing much warming.

      Serious question: Why do you think so?

      The rapid rise in atmospheric CO2 in the past ~150 years is essentially an impulse to what is admittedly a complex system. The "demonstration" is that system at something much more closely resembling steady state. So while this "demonstration" isn't a smoking gun of what will happen, but a suggestion of what is possible once the system settles (since I'm not sure we have a comparison of solar output, etc). But it's certainly not evidence that CO2 "isn't causing much war

      • Serious question: Why do you think so?

        Because with the CO2 levels we have, predicted rise is only around 2C.

        The same CO2 levels that once had the atmosphere at a far greater degree of warming.

        Thus there must be some other factor involved in warming climate besides CO2 alone.

        The rapid rise in atmospheric CO2 in the past ~150 years is essentially an impulse to what is admittedly a complex system.

        Correct.

        a suggestion of what is possible once the system settles

        Serious question for you - why would you assume t

        • Serious question for you - why would you assume the earth would settle at CO2 levels we have now? Since the rise is artificial, once the CO2 is absorbed back into the system, and human output decreases over time (inevitable given the uptake in alternative energy), WHY would you, or how could you assume the CO2 levels today are anywhere near a steady state?

          Fair question, and perhaps I shouldn't, but not really for the reasons you're pointing at. A better assumption (barring large scale CO2 removal efforts) would have steady state (for purposes of human time spans) be higher than where we are now, into mostly uncharted territory (> 5My).

          Indeed a rise of 2C of warming means lots more flourishing plant life around the globe. Guess what plants absorb from the atmosphere...

          Yes, thank you for pointing that out. /s

          While I too agree that CO2 will likely be absorbed back into the system, even the sharpest drops in CO2 concentration in NOAA ice core data have a drop of ~100 PPM over 10,000-20,000 y

    • by barakn ( 641218 ) on Wednesday April 03, 2019 @12:50PM (#58379252)

      No, it's not a demonstration that CO2 by itself is not causing much warming. The Pliocene warming occurred over a time span of 2.7 million years, and our CO2 has only had a century to do its work.

    • This is yet another demonstration that CO2 by itself is not causing much warming. There are other factors involved, including solar output...

      Yeah, all we have to do to stop the sun from shining, then it won't matter how much CO2 is in the atmosphere.

      It's like arguing that it was the gravitational attraction by the Earth on the brick that killed you, not the fact that I dropped a brick on your head.

  • Quiet... (Score:4, Funny)

    by jfdavis668 ( 1414919 ) on Wednesday April 03, 2019 @12:21PM (#58379024)
    Don't let the lumber industry hear about this.
  • by ghoul ( 157158 ) on Wednesday April 03, 2019 @12:22PM (#58379042)

    Co2 is plant food. the more Co2 the more plants and a greener world. Just what do climate change opponents have against trees?

    • Just what do climate change opponents have against trees?

      Pretty tricky to grow lush, green trees across vast swaths of land that have turned to desert.

      • Re: (Score:2, Insightful)

        by ghoul ( 157158 )

        A warmer world means more rain and the Sahara and Australian desert turning green. What makes you think hotter means dryer?

        • by Oswald McWeany ( 2428506 ) on Wednesday April 03, 2019 @01:27PM (#58379500)

          A warmer world means more rain and the Sahara and Australian desert turning green. What makes you think hotter means dryer?

          It's a little more complicated than all that though. Some places will see more rain, often too much rain, the kind that causes seasonal flooding; many other places will become much drier.

          Less of the rain that falls will be in the form of snow, meaning the summer run-offs from mountains will be less; as a result it will be lots of rain, but over a short period of time. Ironically, this means people will be less able to capture water without extensive reservoir and water retainment systems. As we get more rain, we'll have less water to use.

          It means many agricultural economies set up on arable land will collapse as the ideal places to grow crops moves to places that don't have the infrastructure set up to grow and harvest them- and by the time they build those infrastructures, if warming continues, the ideal growing places will move again. Because of our lack of ability to capture the more seasonal and more "all-in-one-go" type rains that accompany global warming, we will have less water to irrigate crops with.

          So yes, more rain, but not necessarily more usable water. A tree won't benefit from increased rainfall if it all happens in one month of the year and the tree experiences drought like conditions the rest of the year.

        • Because in the dry areas, hotter means dryer? Moron?
          Hotter means only more wet in wet areas ... and even that is not granted, see Thailand, Isaan, or California.

          Why are you posting here? You have no clue about anything. Are you paid to post here?

      • Comment removed based on user account deletion
      • by lgw ( 121541 ) on Wednesday April 03, 2019 @01:08PM (#58379396) Journal

        Nah, it goes the other way. Much more rain on a Warm Earth. Of course, last time is was ferns, not trees, but plant life was so vigorous that it supported herds of 40-ton herbivores.

        We know a Warm Earth supports far more life than out current ice age Earth - it's the transition that's worrying. Humans like our territorial boundaries, and if all the arable land moves, even if there's vastly more at the end, there will be wars.

        But the problem is humans, not the ecosystem.

         

    • the fact that we aren't trees
      the fact that many parasites will thrive in a hotter climate
      water is also plant food
      guess you won't mind a bit of flooding in your house every spring
      what do you have against plant food

    • by crow ( 16139 ) on Wednesday April 03, 2019 @12:38PM (#58379142) Homepage Journal

      The big issue is that in the past, these changes have taken place over thousands of years. This could happen over decades. We just can't adapt that quickly.

      The sea level rise is the big issue. We're talking about flooding many major cities. We'll try to add sea walls and such, but if we're talking 10+ meters, that won't work.

      And without the sea level rise, we're fine as a species, but much of nature isn't, and isn't going to adapt fast enough. We're talking about a major extinction event. Yes, in some cases, this will help agriculture, but the benefits will be dwarfed by the problems.

      • by ghoul ( 157158 )

        You claim the benefits will be dwarfed by the losses. I claim otherwise and while your benefits are in the future mine are here and now - more rain in Africa== more crops== less people starving to death.

      • Serious question, but do you have any sources for your claim that we can't adapt that quickly? I actually think the opposite, that tens of years is plenty of time to adapt. The changes aren't instantaneous, we can measure rising sea levels (currently in the mm per year range) and plan appropriately for it.

        Similarly with nature, tens of years is many generations for most species, how do we know they cannot effectively adapt (which is the one thing organisms have been adapting to do since the start of li
    • Even NASA has no real choice but to admit that.

      https://www.nasa.gov/feature/g... [nasa.gov]

      Of course we are all doomed regardless.

    • By YouTuber Professor Stick. [youtube.com].

      TL;DW, plants "breath" through little holes and they lose water when they breath. The close those holes to prevent water loss. They have to balance water loss and CO2 intake. As temperatures rise they'll take in less CO2 to avoid the water loss. Making increased CO2 a bust for plant growth in many if not most cases.
  • Dibs on rice paddies and wheat farming in Patagonia. Easy access to Asia, Europe, NA without Panama canal. yay!
  • Long before sea levels rise 20 m, annual weeds would have become perennial. Bugs and vermin killed by annual frost will thrive year around. Pesticide and weedkiller usage will skyrocket, and all the farm hands will die of cancer or leave the fields. When the North American break basket is lost, the global famine will wipe out most of the infrastructure and civilization. The surviving Homo sapiens postapocalipsia will simply pitch their thatched huts on higher and higher ground from the seashore.
    • Farm hands? You know they have self driving tractors now right?
    • Re: (Score:2, Informative)

      by crow ( 16139 )

      I disagree. Sea level rise is the threat that we can't mitigate. Farms can shift to different crops. We can tweak the DNA of existing crops to adjust as needed, potentially protecting them from new pests. Yes, we have a public health threat looming, but we can manage it. It will be a disaster for the fishing industry, but we've been overfishing for years, so that's not unexpected even without climate change.

      But there's not much we can do about sea level rise except move, and we've put massive infrastru

      • ..or, you know, we could stop dumping so much goddamned CO2 into the atmosphere.
        Just sayin'..
        • by crow ( 16139 )

          Yes, but then the question is how much of the excess already in the atmosphere will get pulled out by natural activity? Or have we initiated processes that will cause more carbon to be released?

      • Moving people/stuff further from the oceans won't be an issue either. Food will be plentiful, animal species will flourish. Judging from past warm earth evidence, it won't be so bad....
      • by ghoul ( 157158 )

        Netherlands is an entire country below sea level. Given enough money (which fossil fueled development can generate) nations can build similar defenses. That gives enough time to move to higher areas.
        The building of flood defenses is just as good a way of pumping money and jobs into an economy than building a military bigger than the next 20 militaries.

    • by Rick Schumann ( 4662797 ) on Wednesday April 03, 2019 @12:56PM (#58379306) Journal
      Or, you know, we, as a species, could stop being pants-on-head stupid about this, get our collective fingers out of our collective ears, uncover our collective eyes, actually acknowledge this shit is happening and it's at least in part our fault, and actually DO something about it.
      Just sayin'..
      • we, as a species, could could stop being pants-on-head stupid about this, get our collective fingers out of our collective ears, uncover our collective eyes, actually acknowledge this shit is happening and it's at least in part our fault, actually DO something about it.
        Just sayin'..

        Spot on. For example, just think of the reductions "we" could achieve were "we" to cut back on banal moral preening on the internet.

        Just sayin'...

      • That is fair, however any plan we're contemplating which may damage the economy in such a way that people simple starve now vs. in the future isn't realistic just to "do something".

        In my younger days, I used to be a staunch environmentalist and would ridicule those bringing up economic interests as stupidly "thinking about money" when so much more important matters were on the table. When I got older I realized economic concerns deserve as much of a priority as anything else - "money" is actually a proxy
    • by ghoul ( 157158 )

      Most of the world manages to farm just fine without an annual frost. Wake up and smell the Tea. North Am is not the breadbasket of the world. The Ganges Delta and the Yangtze Delta produce most of the human food in the world. Losing North Am would mean no more Beef or Pork but humans would be just fine (Humans dont eat the shit North Am farmers grow. They grow animal feed not food)

  • When new animal species (including our ancestors) sprang up, existing species diversified and successfully spread across all the continents.

    Sounds good, man. I can hardly wait.

    • by crow ( 16139 )

      That works much better when change is gradual.

  • Although drowning NYC - I have mixed feelings about that ;-)
  • Last time the CO2 levels where that high, Antarctica, the continent in question, was not at the south pole ... wow, a no brainer. Firth of all the continent had not drifted so far and secondly the earth axis was different. No idea why "climate researchers" don't know basic stuff like this. (There was even a period where Antarctica already was down there, but the earth axis was in a position that half of it was in tempered zones ... one idea why some people think the mythical Atlantis could have been there b

  • The weather is nuts. That's obvious. What to do about it is not at all obvious. And any "solution" that doesn't have China and India on board isn't a solution.

    The world will come to an end in 12 years. It's on the internet, so it must be true. AOC said so, so it must be true. How will people to do their best to make the world a better place if they've already given up?

    Personally, I see it as an opportunity. Consider how we could increase agriculture productivity if temperate and northern climates had lo

The unfacts, did we have them, are too imprecisely few to warrant our certitude.

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