Accuracy of An Inconvenient Truth

[bascule]

Well, at the behest of Pangloss I'm making a new thread for this. He disagreed that the key points of Al Gore's crazy new global warming movie, An Inconvenient Truth, are valid.

 

Actually, there's a few things I do want to address whose validity I dispute (well, not so much validity as scientific knowledge). But I'll try to summarize them here:

 

1. Global warming is real

 

The general nature of the Earth's radiative imbalanche has been well-understood for over a decade. We know the Earth absorbs more energy than it radiates, so there can be no question of this, really.

 

2. Anthropogenic forcings are the primary cause

 

Again, there's been little scientific debate about this for quite sometime. The debate lies entirely within the specifics. But anthropogenic forcings outnumber natural forcings in both scope and intensity

 

3. Global warming will result in a catastrophic loss of both human and animal life

 

The nature of climate vulnerabilities is still rather speculative in nature, but in general we're seeing an extreme potential for water vulnerability in the coming years, which in and of itself could cause massive loss of life. As to whether we'll have "100 million refugees" or see sea levels rise to where Al Gore claims they will is another matter entirely.

 

4. Global warming is causing increased storm intensity

 

I believe this is correct, but Al Gore portrays it as undisputed, scientific knowledge. His key source for this is likely to be the Webster et al 2005 which demonstrated a correlation between increasing SST and hurricane intensity, however at least two papers, Klotzbach 2006 and Michaels et al 2006 have come out contradicting the Webster paper's findings. Gore further draws a direct connection between the devistation wrought by Hurricane Katrina and global warming, something I really disklike. I think Hurricane Katrina was more indicitive of the need for better civic planning than it was the effects of global warming.

 

5. We have passed the tipping point and global warming will continue to accelerate out of control

 

I think we have too little knowledge of nonlinearities and feedback loops within the earth's climate system to really judge when we've passed the tipping point. I'm guessing we're probably quite near it if we haven't passed it already (and by tipping point, I really mean a number of tipping points which affect a variety of different feedback loops within the climate system), but again, that statement is not scientific and is still being disputed. There are certain tipping points which do appear to have been passed, for example, one which occurs when the surface albedo of melting sea ice is flipped almost diametrically as the same surface the highly reflective sea ice covered becomes highly absorbant ocean water. Those who disputed the global scope of melting polar ice (including myself) have really been put in their place by a recent series of papers documenting the simultaneous melting of both Arctic and Antarctic sea ice. (or rather, a continuous decrease in average levels of summer sea ice)

 

Overall I think the movie is a good presentation of recent climate science research, but the papers he presents are cherrypicked to meet his alarmist agenda. I think his brainchild Kyoto was a pathetically stupid idea and I think Bush made the correct decision in refusing to go along with it, although I think he did so for the wrong reasons. Overall, it's still a good movie and I would certainly recommend it.

[j_p]

An important concept is the tipping point; non-scientists believe that progession is 'naturally' linear.

 

People do not understand that complex systems are buffered, and that when the buffering capacity of the system is out-stripped, change is rapid, drastic, and irreversible in the short term.

[SkepticLance]

bascule.

As you know, you and I do not always agree on global warming issues, since I am a skeptic and you tend to agree with the 'humans are causing catastrophic warming' hypothesis.

 

However, I commend you on your posting. I think you are one whose feet are pretty much on the ground, and you see through a lot of the nonsense.

 

Your points 1 and 2 are correct.

Your point 3 is, as you say, speculation. To predict catastrophic loss of life is premature at the least.

Point 4 is also unproven. This is not the first time in history that there have been more than the normal lot of serious hurricances.

Point 5 - past the tipping point. Well, how the hell can anyone say that? The tipping point itself is a purely speculative construct. The world has warmed and cooled more times than I can count. It always rebalances.

 

I am pleased that you have expressed the facts accurately, even if your interpretive bias is a little different to the way I interpret these facts.

[j_p]

The world has warmed and cooled more times than I can count. It always rebalances[/i'] [emphasis mine]

 

Well, if we are concerned about the world as a whole, we probably have nothing to worry about. But most of us worry most about ourselves, our descendents, our societies and our species.

 

I believe humans are capable of causing catastrophic change.

[SkepticLance]

j_p

 

I seriously doubt the vulnerability of the human species. If anything is vulnerable, it is currently endangered (non-human) plants and animals.

 

Humans are, in my opinion, the most adaptable mammals. We are the only species, to my knowledge, that has colonised, unassisted, every continent without changing into a range of different new species to permit adaptation. Our cultural and technological flexibility is such that we can adapt in those ways to environmental change.

[bascule]

As you know' date=' you and I do not always agree on global warming issues, since I am a skeptic and you tend to agree with the 'humans are causing catastrophic warming' hypothesis.

 

However, I commend you on your posting. I think you are one whose feet are pretty much on the ground, and you see through a lot of the nonsense.[/quote']

 

Thanks. The head of my former research group was often mislabled as a "global warming skeptic" himself. However, what that really meant was that he would question the scientific validity of certain findings.

 

I seriously doubt the vulnerability of the human species. If anything is vulnerable, it is currently endangered (non-human) plants and animals.

 

I don't think anyone is trying to argue that global warming will bring about the extinction of humanity. However, that doesn't mean that millions aren't at risk of dying due to climate change, especially in Africa.

[scicop]

FYI: this weeks "Science" p 1307 has a little blurb about how a PI (Curt Davis) is peed-off about Global Warming skeptics who are skewing his data to get their unsubstantiated points accross. I'll have to check out his work.

 

and I think it was a great effort by Al Gore to do this movie. Sadly its in only a few theaters here in NYC. People are too dumb and would rather see a stupid movie about mutant humans who have dumbass powers and intellects.

[j_p]

j_p

 

I seriously doubt the vulnerability of the human species. If anything is vulnerable' date=' it is currently endangered (non-human) plants and animals.

 

Humans are, in my opinion, the most adaptable mammals. We are the only species, to my knowledge, that has colonised, unassisted, every continent without changing into a range of different new species to permit adaptation. Our cultural and technological flexibility is such that we can adapt in those ways to environmental change.[/quote']

 

We, our cultures, and our more advanced technologies are suprisingly fragile. Katrina, for example, did not indicate that we are particularly adaptable, in either the short or long term.

 

Other species, with greater populations, will have a better opportunity to evolve in response to a catastrophic change.

 

Rats and roaches rule.

[herpguy]

I really want to see this movie, but it just stopped playing in the only theatre near me.

 

I agree that we are the most adaptable of mammals simply because we are great problem solvers. I also disagree that global warming will drive the human race to extinction as a whole. However, humans will definetly be driven out of many of the Pacific Ocean islands, parts of Africa, and other very vulnerable places.

[SkepticLance]

j_p

I think you may have missed my point.

Humans moved into all continents without evolving.

We are adaptable precisely because we do not need to evolve in the biological sense to adapt to an environmental change. Changes in culture and technology serve us in a way that is far superior than simple biological changes. It is much quicker for a start.

[Pangloss]

I wish you'd told me about this thread, I don't normally read this particular board.

 

I agree more than disagree with you, Bascule. I agree with the point that global warming is "real", I just think the case is consistently overstated, and it's done for no good (i.e. scientifically useful) reason. The most consistently applied (and only useful) application of global warming research is "making Republicans feel bad", not "saving the planet" as is claimed.

 

But when I say "we shouldn't proceed on the assumption that global warming is real", that doesn't mean I think we should continue burning fossil fuels with abandon or ignoring the obvious consequences of air pollution. What it means is that I think we have sufficient motive AS IS for cleaning up those problems, and we are making progress in resolving them, so what's the problem?

 

The thing that really gets me is the way some (*not all*) skeptics and scientists will complain bitterly about the religious right when it comes to stem cell research or birth control, but when it comes to global warming they become the most closed-minded, faithful zealots around.

[bascule]

Salon did an article on the scientific accuracy of an Inconvenient Truth:

 

http://www.salon.com/news/feature/2006/06/10/truths/index_np.html

 

Their take:

 

The usual oil industry flacks and dogmatic skeptics have surfaced to denounce Al Gore's global warming movie. But climate scientists say that, basically, he got it right.

[bascule]

I wish you'd told me about this thread, I don't normally read this particular board.

 

Yeah, probably should've linked it from the other thread.

 

I agree more than disagree with you, Bascule.

 

Yay!

 

The thing that really gets me is the way some (*not all*) skeptics and scientists will complain bitterly about the religious right when it comes to stem cell research or birth control, but when it comes to global warming they become the most closed-minded, faithful zealots around.

 

I used to work for a "global warming skeptic" (he hated being called that, by the way). I think you'll find my history of posts about global warming as taking a rather skeptical perspective (just ask herpguy, as I've argued with him more than anyone).

 

However, I've also been wrong in my skepticism on a number of occasions (which happens when you're a skeptic... if you doubt because of lack of evidence, you shouldn't be surprised when someone manages to present evidence contrary to your position). Specifically, it's been demonstrated conclusively that the average summer areas of Antarctic sea ice are, in fact, decreasing consistently, and the data that showed aimless fluctuation were incorrect. This completely undermines my argument that the climate forcings responsible for the melting of Arctic sea ice are regional and not global in scope.

[SkepticLance]

bascule.

There was a time, I think about 12 years ago? when the sea ice round parts of Antarctica was shrinking. The media called it global warming.

 

There was a second time (about 5 years ago?) when sea ice round Antarctica was expanding. This was also called global warming. Apparently warmer conditions meant warmer, moister air, and bigger snow dumps.

 

If global warming causes sea ice explansion, and global warming causes sea ice shrinkage ......

[bascule]

There was a time, I think about 12 years ago? when the sea ice round parts of Antarctica was shrinking. The media called it global warming.

 

The moral of the story: climate science reporting sucks. If you want the real story, you should be reading scientific papers, not news articles.

[SkepticLance]

bascule.

Both stories quoted climatologists.

[bascule]

bascule.

Both stories quoted climatologists.

 

Did the climatologists in question even write the papers that were being reported on? Even so, they may have been taken out of context by the reporter.

 

Reporters have their own motives/agendas and lack the background to even understand the papers they're reporting on. Perhaps one of the best examples is the Webster et al. paper I referenced above, which was reported to the public as "Global warming causing stronger hurricanes," even though the paper only demonstrated correlation, not causation. And, as I added before, two papers came out challenging that assertion as well.

[SkepticLance]

bascule

I guess the point I was making is that global warming has come to be used as the 'explain all' mechanism, for almost anything related to climate or weather. I am sure you will agree with me when I say that is not justified, and we should be sceptical of those who so use it.

[bascule]

I believe an overabundance of attention is placed on greenhouse gasses, primarily CO₂. While I doubt there are many credible climate scientists who will question the idea that CO₂ is the primary anthropogenic forcing affecting the climate system, it certainly isn't the only one. Furthermore, forcings that are global in scope receive and overabundance of attention, while regional forcings are almost completely overlooked. I think more attention needs to be paid to the regional scale/mesoscale, and that combined work at eliminating regional warming could dramatically impact the global climate system in ways attempting to curb greenhouse gas emissions cannot.

[Dr. Dalek]

Given that the amount of CO2, produced by mankind annually is only 2% of all the CO2 (the rest being natural) produced, I would say there is an over emphasis on CO2.

Quite frankly I doubt much human impact in the way of CO2, or greenhouse gasses because the supposed climate scientists and environmentalists can't get there stories strait! I also doubt that Global warming will bring about end of the world!

The only thing related to man made climate change I would give attention to would relate to surface albedo. Cities absorb tremendous amounts of heat and are often located near water. Water temperature effects the weather and therefore the climate.

Granted the effect of heating up water near cities would not bring about the end of the world, and probably would not cause too much trouble altogether, but it is something to think about.

[SkepticLance]

bascule.

I believe you are over-impressed by computer models.

Extra-ordinary claims require extra-ordinary evidence. The claim that humans are driving the entire world into substantial warming is, indeed, extra-ordinary.

 

In science, the only evidence that is truly acceptable is Empirical. That is: real world experiments or observations. Processes of logic and computer models do not qualify.

 

Computer models certainly have their place, and can be invaluable research tools. However, like any scientific hypothesis, they must be backed up by empirical evidence. In the case of human driven global warming, the empirical evidence required must be very solid and very convincing.

 

bascule, can you supply such evidence? And I don't mean evidence of warming. We all know that is happening.

[Mokele]

The claim that humans are driving the entire world into substantial warming is, indeed, extra-ordinary

 

How so? I mean, there's 6 billion *huge* mammals running around massively altering their environment and burning lots and lots of stuff. That doesn't sound like an extraordinary claim to me; it sounds quite reasonable. An extraordinary claim would be something like all of the CO2 increases are due soley to increased farting of ruminant herbivores.

 

In the case of human driven global warming, the empirical evidence required must be very solid and very convincing.

 

The problem is that you're never going to have truly wonderful evidence for it, ever, even if people *are* the cause. You can do correlational studies with the past, using various past measurements, but those get attacked all the time anyway since correlation doesn't equal causation. You can use computer models to make predictions (and, FYI, the major source of variation in climate models isn't the effect of CO2, it's how much humans release, how many of us there are, etc), and check those, but in such a complicated system, they're never going to be perfect.

 

In fact, the *only* way we can conceivably get better evidence than now is by direct experimentation, and I don't happen to have any spare planets lying around for us to use.

 

 

Basically, that's my gist: I don't think it's such an extraordinary claim, and I don't see the evidence getting much better over time. Finer resolution, perhaps, but never enough to eliminate any doubts. However, policy decisions must be made, and to discard something simply because the evidence isn't perfect is foolish, especially when the constraints of the field limit the availible evidence.

 

Mokele

[bascule]

Computer models certainly have their place' date=' and can be invaluable research tools. However, like any scientific hypothesis, they must be backed up by empirical evidence. In the case of human driven global warming, the empirical evidence required must be very solid and very convincing.

 

bascule, can you supply such evidence? And I don't mean evidence of warming. We all know that is happening.[/quote']

 

SkepticLance, I don't think you understand how models work. We can test the validity of something like a General Circulation Model by giving it model input from the past and seeing how well it predicts the present. That's exactly what the Hansen et al. 2005 paper did, for example. I don't believe we can skillfully perform multi-decadal simulations of the climate system yet, due to uncertainties about certain non-linearities and feedback loops in the climate system.

 

I suggest you read the 2005 National Research Council report if you'd like a better understanding of how our knowledge of anthropogenic climate forcings is derived. General Circulation Models are only a small part of how we derive our overall understanding.

[SkepticLance]

bascule

We have had this discussion before. As you know, I am not prepared to accept computer models in place of empirical evidence. Models have proved fallaceous in non climate situations numerous times, when variables not taken account of exert their influence. It may well be the case with climate models also.

 

Also, the proper practise of science requires empirical evidence. We do not have to experiment on spare planets. Lots of other possibilities exist.

 

Let me ask again. Can you supply strong empirical evidence to show that human activity is the dominant driver of global warming?

 

The other day I was reviewing an article in a back issue of New Scientist. 27 August 2005. The subject was shrinking glaciers. They included a graph of the average shrinking of 169 glaciers world wide. The graph showed steady shrinkage from about 1810 to 2000 AD. Since greenhouse gases have increased very little before 1910 AD, the first half of the graph was clearly warming caused by something other than anthropogenic greenhouse gases. Yet, the graph shows no difference in shrinkage rate after that. It makes me a bit skeptical of the idea that warming from 1810 to 1910 was 'natural', and an exact same degree of warming from 1910 to 2000 was 'unnatural'.

 

To prove to me that something changed, I need strong empirical evidence.

[bascule]

Let me ask again. Can you supply strong empirical evidence to show that human activity is the dominant driver of global warming?

 

Let me answer again: Read the NRC report. Or the IPCC report. All of these are chock full of empirical evidence of anthropogenically forced global warming.