Slashdot Mirror
Global Anoxia Ruled Out As Main Culprit In the P-T Extinction
Garin writes "The late Permian saw the greatest mass extinction event of all-time. The causes for this extinction are hotly debated, but one key piece of the puzzle has recently been revealed: while the deep-water environments were anoxic, shallower waters showed clear signs of being oxygenated. This rules out global anoxia, and strongly suggests that other factors, such as the Siberian Traps vulcanism, must have played a dominant role. From the article: 'Rather than the direct cause of global extinction, anoxia may be more a contributing factor along with numerous other impacts associated with Siberian Traps eruption and other perturbations to the Earth system.' See the full research article (behind a paywall) here."
or not...
The meteorite in the Yucatan was at the end of the Cretaceous period, they are referring to a proposed impact over 400 million years earlier due to some discoveries of a potential 300 mile wide impact crater in Antarctica... The Cretaceous extinction even only killed off about 75% of species as compared to 90% being killed off in the extinction that this article is about.
Apparently, the super volcano in this case erupted for nearly a million years, warmed the oceans to 100 degrees F and forced all organic growth (as measured by coal deposits) to the poles. Whether caused by an impact or mantle event, it would be incredibly destructive to any 'society' living on the planet
I knew Dr. Spock was the one that killed the dinosaurs, "Captain, these giant bird-lizards are highly illogical and must be disposed of."
Monstar L
And this is why people laugh at Deniers as they have no idea of the science or the problem.
I read anoxia as anorexia.
At least you didn't read it as dyslexia.
Sheesh, evil *and* a jerk. -- Jade
How does "Once all trapped CO2 will be released" [in the future] equate to "400 PPM" which we have already past.
Perhaps your reading skills need a polish.
Oh, don't worry. Humanity will survive. Unless we kill each other in the attempt to stay dry.
The main reason why this wasn't a big deal about 12,000 years ago is simply that there was plenty of room and very little in terms of population. Moving inland when your coastal area was being flooded wasn't that big a deal (not to mention that the gods were to blame for it and who could argue that people have to move when their gods tell them to?).
It just MIGHT be a bit different today when I really don't feel like sharing my apartment with people who don't wanna live under water.
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
I read anoxia as anorexia.
90% of all species died... but they were looking very stylish right up to that point...
You have the right to remain sentient. If you give up the right to remain sentient, you will be elected to public office
First: you might have logged in for this post and given it your cred, even if it was your first post.
Children asphyxiating at 400 ppm CO2 is completely unrealistic. It is hyperbole. It is absurd. At 40,000 ppm it might become credible, but 40K ppm is not plausible if we cooked off every potential fossil fuel including methane clathrates, every bit of limestone and every bit of granite on the surface of the Earth two miles down. It's not going to happen unless the kid is asthmatic, and then pollen or mold is more likely his issue. Bringing children into it at all is "think of the children" emotional escalation.
If you're going to fight the good fight, bring a real problem. If you don't have a real problem to bring you might reexamine the basis of your religion. Ah, who am I kidding? You will find a way to rationalize your position. You're already excusing people who would describe 400 PPM of CO2 as "asphyxiating children". You'll probably find a way to compare me to Hitler.
Help stamp out iliturcy.
Well, some people do care whether other people can survive. The point is simple: People will want to survive. If necessary, by floating on your corpse.
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
Sure, read Skeptical Science. Those quoted figures are from one single location and may not reflect what was happening elsewhere. This site is an excellent example of good science and they have extensive responses to the common denier arguments. I would recommend spending some time there.
Also, keep in mind that the issue is what is forcing the increase. The 400PPM is not going away in our lifetime nor our grandchildren's lifetime. This problem will get worse not better. And of course 12,000 years ago the population was a lot smaller. The total world population probably never exceeded 15 million inhabitants before the invention of agriculture so with 7 Billion people alive today the impact of a warmer environment is likely to be higher than it was 12,000 years ago.
I read it as anxiety. Should I worry about that?
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
he Earth's climate was warmer before than now as little as 12,000 years ago.
No, it wasn't. 12,000 years ago was just after the end of the last glacial.
Before that it was mostly uninhabitable by humans for 100,000 years except for some equatorial regions because: ice.
No, it wan't. Glacials certainly don't make "non-equatorial regions" uninhabitable. At the height of the last one, most of the US and more than half of Europe were certainly inhabitable.
Ezekiel 23:20
Well, that's also a position to take, but the problem is that people who built their houses there for whatever dumb reason won't simply go "oh well, I was dumb, here I sink, farewell dear world".
They'll come to YOU and want YOUR home. Whether they get it and kick you out or die trying doesn't really matter much, considering that they have no real option.
And somehow I don't feel like fighting someone who cannot back down.
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
Maybe by the time we are done with this planet, P-T will look like a cakewalk in comparison.
Well, our "mass extinction" has already resulted in a global, industrial society so it's well ahead of the P-T extinction already.
Comparing the Eocene with modern AGW is like comparing parking your car at the mall with crashing your car into a tree: They both involved trips where the car reduced its speed from 60 to 0 MPH.
Given that we show every sign of running the CO2-enhancement experiment to completion, it is reassuring to know that this low-probability but extremely-high-cost outcome is that much more unlikely. (To my warmist comrades -- given a choice between losing a toe, a leg, or a life, we know which choice we would most want to avoid, but that does not mean the remaining choices are good. Anoxia is among the worst of the outcomes, far worse than the middle of the US becoming uninhabitable or the seas rising 100 feet. And to you denier bozos -- greenhouse science is cut-and-dried stuff, with only the detailed outcomes unclear, but it's also clear that between natural human greed and your foolish efforts, we will almost certainly burn all the fossil fuels we can until something truly alarming occurs. Perhaps we have overestimated the effects of the current CO2 levels -- but that's okay, we're just going to keep on burning it till we see an effect, and a big and unambiguous one.)