faetal on 14/8/2012 at 11:25
I've just re-read your post and my point stands. It seems I'm not the only one to take issue with it either. You are using flawed logic. You said very clearly that because a mass extinction can occur without humans that you
conclude that we can not cause a mass extinction. The fact that you say we should be reducing emissions is let down by the fact that you pepper the sentences with uninformed opinions that humans are not the primary cause of the warming trend we are seeing despite the (
http://en.wikipedia.org/wiki/Scientific_opinion_on_climate_change) scientific consensus being 90% sure of humans being the primary cause.
In the end, it boils down to one side saying "our scientists say X = true" and the other side saying "our scientists say X /= true."No. It is more 90% says it is true, 10% say it is not true, so it really comes down to having the intelligence to not assume that an argument with two sides is automatically equal at both ends.
Vivian on 14/8/2012 at 11:29
There are great big islands of plastic and other crap (like, 1000s of km2 of it) at the still centre of most of the circular ocean currents. We cut down rainforest. and boreal forest. all the forest. Shitloads of it. We build cities and roads everywhere, heat up the rivers and seas, move species around either on purpose of by accident (always ends badly), let our pets run rampant and hunt keystone species into oblivion. You can't palm off the current mass extinction (which is a real thing, (
http://en.wikipedia.org/wiki/Holocene_extinction) refs here) as anything other than caused by humans. Species are literally disappearing faster than we can count them, and there don't seem to be any supervolcanoes, comet impacts, solar radiation storms, geomagnetic reversals or any of the other usual suspects happening. Just us, being dicks.
Not to say we can fuck things up irreversibly, which I guess might have been your original point Sg3 - life on earth would be pretty difficult to totally eradicate, and we do create new niches as we expand. Urban scavenger is pretty much inevitably going to be the most popular ecological niche sooner or later, unless we all die or something. But yes, we are doing what the end permian event (supervolcanoes, btw. Seeing as (
http://en.wikipedia.org/wiki/Michael_Benton) Michael Benton was my MSc super I might as well throw in with his theory. Besides, it's a pretty good one) took a few hundred thousand years to do, and we're doing it in a few hundred.
jay pettitt on 14/8/2012 at 11:33
Quote Posted by heywood
Be careful with that argument because correlation isn't causation. Skeptics will jump all over it pointing out that CO2 lags temperature in the ice core record. There's an inverse relationship between temperature and the solubility of CO2 in water, so changes in ocean surface temperature have a major effect on atmospheric CO2 flux. The lag in the ice core record doesn't invalidate the greenhouse effect of increasing CO2 so it doesn't disprove anthropogenic warming...
The skepticons get exercised about all sorts of things. They're almost always wrong.
CO2 lag doesn't just not 'invalidate' global warming. It's a critical piece of the puzzle that helps validate our understanding of CO2 and quantify the effects of greenhouse gases.
Obviously there's a difference between a scientific understanding and what goes on in the public debate, but it'd be a shame if we had to tip-toe around anything that sets the hobby cynics off - given that setting themselves off at anything is their raison d'etre.
Quote:
but it does suggest that post-glacial warming periods weren't initiated by CO2 release.
As far as I know (I'm no expert) there's only one interglacial that was potentially triggered by CO2. The rest were mostly orbital. The enhanced greenhouse effect from CO2 feedback (the lag) is then required to turn a relatively weak orbital forcing into a global event.
Muzman on 14/8/2012 at 18:39
Quote Posted by Sg3
Muz, one of my college courses took us through, in survey detail, both sides of the argument. There's some pretty good stuff on both sides--that you have only seen good arguments (or arguments which you consider good) on one side does not mean that it should be clear to all that "your" side is correct, nor that the other side has no good arguments.
In the end, it comes down to one side saying "the scientific evidence shows that X is true" and the other side saying "the scientific evidence shows that X is false." That is all, I'm afraid--none of you here espousing either side of the argument have done the requisite research (which would take a lifetime of dedication to perform--and even then the results should not be free from doubt, even to the one who performed the research), but you are instead relying entirely on hearsay, all of which is (unfortunately) very tainted by political motives.
I believe this should be my final post in this argument, because the past few posts have ignored critical points I have made, while jumping on and inflating others--and assuming wrongly about my beliefs and intentions. This sort of knee-jerk reactionary behavior is proof that nothing I say will be taken at face value, which renders discussion quite pointless. It is, indeed, only the purest optimism which occasioned the writing of this post itself--a foolish optimism, with a desire for a sense of clarification and closure.
I'm glad one of your college courses took you over the arguments. It should be clear to you then that everything I said (while technically hearsay I guess) can be traced directly to the actual scientific evidence with no political massaging or jumping to conclusions along the way (for you will note, I didn't jump to any conclusions not in evidence; such as speculations on what the future holds for this situation, which is really the only point of contention left in the field). Indeed suggesting that this evidence is tainted by political motivations is basically a slur. If you think the facts are wrong or intentionally deceptive, you need to show it. Saying 'it's tainted' is not a 'get out of argument free' card, despite what our internet cynicism would have us believe.
I never said anything about your beleifs or motivations, only your reasoning. Which is that the vague suggestion global warming has occured in the distant past, away from human influence, might question the idea humans are to blame now. This notion does not attend to the facts at all and, indeed, seemingly sets out to ignore them.
Sg3 on 14/8/2012 at 21:34
Quote Posted by faetal
You said very clearly that because a mass extinction can occur without humans that you conclude that we can not cause a mass extinction.
I'll thank you to refrain from attributing to me something that I did not say!
I said that, because a mass extinction can occur without humans, we cannot assume that we are causing a mass extinction. "We cannot conclude that we are causing a mass extinction" very much does
not equal "we can conclude that we are not causing a mass extinction."
It's a common, well-known logical fallacy--"A is not true" does not equate to "The opposite of A is true." The classic example is "I do not believe that there is a god" as opposed to "I believe that there is no god." The two statements aren't at all the same.
Given your intelligence, I can't believe that you made that mistake by accident. It is now clear as space that you are not interested in what I actually said, but would rather just twist my words for "lulz." As far as I'm concerned, this discussion is over. Have fun pretending I said more stuff that I didn't really.
Pyrian on 14/8/2012 at 22:24
Quote:
As far as I'm concerned, this discussion is over.
You keep promising.
You're just going around casting doubt on well-supported scientific conclusions. But that's easy. Anybody can say "well, you can't be
completely sure" about anything scientific and there's some truth to it. But there's not
significant scientific doubt on this general conclusion. Just oil money, dishonest politicians, and those they can fool.
june gloom on 14/8/2012 at 22:43
Oh is this an Sg3 thread? Okay then.
LarryG on 15/8/2012 at 00:00
Quote Posted by Sg3
I said that, because a mass extinction can occur without humans, we cannot assume that we are causing a mass extinction. "We cannot conclude that we are causing a mass extinction" very much does
not equal "we can conclude that we are not causing a mass extinction."
Not exactly. What you said was:
Quote Posted by Sg3
If this Permian mass extinction occurred "naturally," that is, without human interference, then I must conclude that human interference is not the primary factor in such an extinction.
That conclusion is fallacious. That conclusion is what I suspect people (myself included) are reacting to.
Just because events other than those involving humans led to a mass extinction, it does not follow that human caused events can't lead to similar mass extinctions. In fact, the preponderance of the evidence is against your conclusion. It is highly likely that the current global warming trend a) is caused by human interference in natural balances and b) if uncorrected will lead to global catastrophes and mass extinctions.
But again, who cares? Global warming is a fact. Whether we caused it or cosmic frogs from the crab nebula have caused it doesn't matter. What does matter is whether we are motivated enough to take corrective actions which might ameliorate, if not completely prevent, the coming changes.
Don't get so hung up on defending your inference structure and help bale the boat before we all sink.
Yakoob on 15/8/2012 at 02:58
So all the geotalk is going anyone over my head, can someone dumb it down for my little uneducated brain and tell me, on a scale from 1 to "oh god we're so fucked," where we are?
Sg3 on 15/8/2012 at 03:01
Quote Posted by LarryG
Not exactly. What you said was:
Hmm, yes, I do seem to have been mistaken. My apologies, Faetal. And with that, exeunt Sg3 stage down (for real, this time).
