What's all this talk about "Global Warming?"

Great Debates
61

That’s really funny, because you’ve cut to the heart of the matter: there is no scientific evidence that demonstrates that man is the cause of global warming. Models are not evidence. Sure the Earth is warming. But it’s been warming since the end of the Little Ice Age. No one has demonstrated that anthropogenic CO2 is actually causing the warming we have seen. Sure, there appears to be a correlation, but the link has yet to actually be demonstrated. No one has even proposed a falsifiable test.

Now, that’s not to say that we shouldn’t do something anyway, just in case, and pollution is bad in itself but the costs involved are staggeringly vast, putting even the bank bailouts to shame and for an apparently minuscule benefit. So people are going to be sceptical.

AGW proponents also commit a number of sins in labelling anyone who isn’t a fellow traveller a denier, refusing to consider nuclear power, announcing that the subject is settled when it is far from so, and using overblown rhetoric like equating AGW denial with holocaust denial. This does not sit well with The Man In The Street. Not that they’re going to say it out loud, of course.

Perhaps we are lucky that the Sun appears to be going through a period of sunspot inactivity. There has been a good correlation in the past with cold periods. If it continues and there appears to be a significant effect on Earth’s climate, and this stops when the sunspots return in force, then we will know that it is that that is the main driver. But that will require at least one solar cycle - 11 years - if not two, and who knows if the sun will stay quiet so long. Time will tell.

62

(I skimmed through your cite btw, and it was definitely interesting…thanks for posting it)

No, I don’t believe that this is the only conclusion that can be drawn from your example. There were various theories that came together to attempt to explain some anomalies concerning the current configuration of the continents, and one of them emerged as a consensus…and was ultimately proven wrong. Some of the DATA that was used in the consensus view eventually turned out to be quite true, but the theory itself ended up being wrong.

That CO2 is a factor in temperature was not well understood before the 60’s, according to your cite, but it turns out that it DOES factor in. Something I don’t think is really in dispute. What IS in dispute, seemingly, is how much of a factor it is, and what other things might be factoring in. It could be that the GW/AGW folks are right, and atmospheric CO2 is the primary or principle factor causing temperature change…in which case, the current GW crowd would be like Darwin, fighting and eventually winning the day with their theory. Or, it could be that the current theories are wrong, or not complete…in which case a new theory will emerge, or the current theories will be altered or modified to better express the data. At this time I think the latter is more likely than the former, but I ALSO think that this is exactly why we NEED there to be a real debate on this, not an attempt to shut down all debate and simply declare victory.

YMMV, but that’s MY concept of how science works, and to me the best way to prove GW/AGW once and for all is to throw open the debate, to look hard at all the questions, and to not attempt to shut down the other side. Also, it would help, again IMHO, if scientists working on climate studies focused on the science, and no on putting forth their views on how we should ‘fix’ the ‘problem’. To me, by doing so, it creates questions about their motives and impartiality. As I said, YMMV…that’s just how I see it.

-XT

63

Here’s the thing.

Carbon Dioxide is a greenhouse gas.
Humans have been dumping lots of CO2 into the atmosphere in the last 100 years.
CO2 levels have been increasing since we’ve started measuring CO2 levels.
And measured global temperatures seem to be increasing.

So what next?

Global climate has fluctuated wildly in the past, with glaciers covering what is now Seattle and London only 15,000 years ago, to those glaciers disappearing very quickly everywhere except Greenland and Antarctica. And before that for the last 2 million years we’ve went through cycles of large ice ages and large warm ages, with little warm ages in the ice ages and little ice ages in the warm ages.

But we don’t really know why these fluctuations occur. And the changes between warm periods and cold periods seem to occur very rapidly.

So there you go. We’re in a warming period. But we’re also adding material that is pretty much guaranteed to warm the planet. Which means more warming is expected.

What about the effects of the warming? Well, if the Greenland and Antarctic ice sheets melt, we’ll see higher sea levels, just as we have higher sea levels now than we did 15,000 years ago when continental glaciers covered much of Canada and Northern Europe. Right now lots of people live in cities at sea level. How large will the sea level rise be? No one knows.

The problem is that we could be looking at non-linear effects, or positive feedback loops. For instance, ice is white, so it reflects light from the sun back into space. So areas of ice tend to make the earth cooler–when that ice melts due to a warmer planet, the planet gets warmer still because more sunlight is absorbed and less is reflected. Of course negative feedback loops occur too. But as ice melts, and winter snow cover melts sooner, that means warming increases faster, which means more ice melts and winter snow melts even sooner and snow falls even later.

So the problem is that we can’t really predict very well what will happen with the climate, but we know that we could be facing all sorts of changes, and human activity dumping lots of greenhouse gasses into the atmosphere is pretty likely to make those changes more intense and disruptive.

But since we aren’t going to stop dumping CO2 into the atmosphere any time soon, and since even if we stopped doing it tomorrow we’d still be facing climate changes from the CO2 already dumped into the atmosphere, we’d better get used to the idea that we’re going to have to live with the consequences of a different climate than we were used to in the 20th century.

64

If you read the history you will see that the current issue is just like the one you mention: The consensus came to be for several decades that the natural greenhouse effect was not going to be affected by the addition of man made CO2 and other gases to the environment… That idea was ultimately proven wrong.

And this also ignores the history of the last 100 years regarding this subject. Real debates were done before reaching the current consensus.

65

It is the deniers that do want to equate the terms, but that is a silly effort to godwinize.

Denier is an appropriate word in this case, an skeptic would only say that there is a controversy, a denialist will jump to say really silly things like “there is no evidence”

66

I don’t believe that the debate is over, or that the issues have all been resolved to the point where 'real debates were done. I guess time will tell, and we may not live long enough to know how it all turns out. I’m confident enough in the scientific method though that I know it WILL be resolved, and eventually, whatever does emerge, will get us even closer to a solid, viable, testable, reproducible theory. I KNOW this is what will eventually happen, since I am absolutely confident in the progression of science.

It will be interesting to see how this all plays out in the next few years.

-XT

67

That’s true, but (and correct me if I’m wrong here), CO2 is not among the most potent of the GHG’s…in fact, it’s far down the list. No?

That’s true, but temperature has varied widely in the last 10k years, and has been increasing for several centuries now, even before we started dumping substantial amounts of CO2 into the atmosphere. My understanding is that the RATE of temperature might be increasing more recently, and that this might be because of CO2, or it might be because of a number of factors (including CO2)…or that the CO2 might be incidental or even be a following indicator of temperature change (i.e. the amount humans have put into the atmosphere is only a small percentage of what nature puts in without humans factored in). I realize that the consensus of scientists favors the former (i.e. that it’s human CO2 that is the primary or principle factor), but I don’t think that this has been conclusively proven at this time.

That’s true, though we’ve only been measuring it (directly) for a relatively short time period (minuscule by geological time scales), and certainly there have been times in earths past where CO2 levels were quite a bit higher than they are today. I don’t believe that, at this time, all of the mechanisms that factor into increases and decreases of temperature are fully understood, but then my knowledge of this subject is, admittedly, on the far end of ‘low’, and I don’t even pretend to understand even the basics. When Intention and Jshore start seriously discussing this subject my eyes tend to glaze over a bit…

As far as I can tell this part isn’t really in dispute, though my understanding is that, recently the warming trend hasn’t gone up as much as the models suggest it should.

Continue to gather data, refine models, and increase our understanding of how CO2 factors in and the mechanisms of how the various factors effect temperature on this planet.

-XT

68

Since the 70’s most scientists began to accept that CO2 and other gases would become an issue.

(Many, even on this forum, wanted to convince others that there was consensus on the 70’s that we would be headed to an ice age, denialists were wrong on that one too)

CAUTION: contains disco music! :slight_smile:

As the video shows even the science guy filmed by Frank Kapra in the 50’s say virtually the same things as Al Gore said.

So evidence has told scientists something, for more than 50 years now.

Me too, but I do expect to get better answers on where the effects of the warming will be an issue and get a better handle on what other problems could come. And I say this looking at the history, after all this time it is not very likely that the basic science will change, the best chance to dismiss the issue would come not by denying the science, but by finding that there was a missing natural mechanism that would make the problem go away in the future.

69

Are you being dense to be dense?
I said:
“How is it acceptance of a scientific theory is ‘cool’ but when said scientific observation is proved false it is deemed ‘less than scientific’?”

And I said it as a general statement for which countless theories HAVE been proven false but if you follow the route you are on good sir, you’d never have thunk it by reading the statements from you who is so resolved that AGW IS CAUSED BY MANKIND. (even though it may not be)

70

I am considering a strong rebuttal to that last sentence which is offered by you therein which has, good sir wandered off into the woods and now became hopelessly lost.

71

I could not care less about his faith, but if he’s willing to discard scientific priciples because it would contradict his religion, then I see red flags all over.

That’s odd, because you’re on the side that relies on op-ed pieces and nitpicking rather than the science. The science is overwhelmingly on one side of this issue. Where are the peer-reviewed studies refuting AGW? Why does the anti-AGW side constantly harp about Al Gore when he hasn’t contributed anything to the science? The lack of rigorous science on one side of the issue is very concerning, isn’t it, considering your concern over it?

72

That is very possible as I don’t have a horse in this race. I believe AGW exists. I also state that I don’t KNOW the cause. Others in this thread KNOW that we are to blame and if we don’t stop emitting c02 into the atmosphere we will all burn in the fires of Earth.

I just grow tired of the ‘supposed’ knowledge of many posters here. It is almost akin to religious fanaticism at times.

At least I am man enough to say “I don’t know”

73

Well, that is why I recommend the “climate denial crock of the week” short videos by this guy:

Sun activity blamed for the current warming? No good evidence for that.

Contrarians misleading people with graphs (with past warming explained):

Manmade CO2 is the issue now.

Easy understand clips and best of all, he shows you where to check for more information.

74

I also did not know, I came to the realization that there are very few scientists and contrarians going against the consensus. Looking around, I found that in almost all cases their scientific points were clearly replied to with evidence and research.

Just on this message board I clearly remember skeptics (that later were shown to be deniers as they ignore the evidence) claiming with no uncertain terms that one of the basic items for AGW to be considered a problem, the water vapor feedback with CO2, was not real or that the feedback was not as big an issue as reported. And yet, months **before **those skeptics claimed here that CO2 was not doing anything to the water vapor:

It was a moment that showed me that there are no limits some people will go to ignore the science.

75

…Which would be caught by peer review, no? Why doesn’t his science stand on its own like everyone else’s? What exactly are you trying to say? First you said that he’s a legitimate climate science. He’s widely published in the peer review journals. And yet, you see ‘red flags all over’. Are you saying his scientific opinion is not valid? Or what? Are you suggesting that before you read a paper in the scientific literature you should stop and check the backgrounds of the authors, in case they believe things you think put up ‘red flags’ about their work?

Do you know what’s REALLY odd? I seem to be one of the few in any of these debates who’s actually citing the real science, and yet you attack me through association with others who ‘rely on op-ed pieces’.

I guess you’re either unwilling or unable to discuss this issue on the scientific merits, so you’re resorting to sophistry and character assassination and guilt through association to sidestep all the rather uncomfortable information I’ve put in front of you.

Are you paying attention at all? First of all, this isn’t an all-or-nothing deal. Saying “the science is overwhelmingly on one side of the issue” is meaningless, because there are MANY issues. Some of them are extremely well grounded in science, some are highly speculative. Furthermore, the people pushing climate change legislation have no problem using wild speculation as evidence - so long as that speculation makes the problem look worse instead of better.

I have repeatedly posted the IPCC’s ‘best estimates’ values for warming. They truly do represent the closest thing to a scientific consensus we have, but they have huge error bars, indicating there is still a lot of uncertainty. Regardless, the ACTUAL VALUES the IPCC quotes do not generally line up with the alarmist visions of the future pushed by the proponents of political action.

Look, I’ll be happy to debate the issue starting from the assumption that the IPCC’s 4th assessment report represents the current best estimates of science. I’m guessing you won’t like that. 3 degrees of warming and a sea level rise of a couple of hundred millimeters is not going to convince anyone to dismantle the world’s fossil fuel energy infrastructure. But unless you’re willing to accept the IPCC’s actual science, don’t try to lecture me on who is or isn’t scientific.

76

If one doesn’t know wouldn’t it make sense to follow the advise of every major science association in the US and be concerned about AGW?

77

Those estimates of sea level rise are based on thermal expansion of seawater and exclude the influence of melting ice. Add in the inevitable icemelt and we’re talking meters.

See here, in the actual report. (.pdf) Page 13, table SPM.3

And spare me the lectures - I have a degree in meteorology.

78

I’m pretty sure that the influence of meteors is unimportant.

79

Ah, but did you retire 13 years ago, and are now viewed as a paid promoter of the agenda of the oil and gas industry rather than as a practicing scientist? Cause that seems to be the kind of “scientist” that Sam Stone seems to respect.

80

IIRC there are organizations using the IPCC report, but they are using it precisely to now claim that there is no need to do much; they can do that because, as I noticed before, most of the recommended solutions were based on very conservative estimates.

However, that would remain relevant only by assuming no progress or more research was done from then to now.

The Intergovernmental Panel on Climate Change published its last report in 2007. The next IPCC report is not due until 2013. In the interim, some of its lead authors have just published The Copenhagen Diagnosis to update climate science in time for the Copenhagen talks.

http://www.copenhagendiagnosis.org/