Headline from the Canadian, via Hit and Run:
"Over 4.5 Billion people could die from Global Warming-related causes by 2012"
In case you are struggling with the math, that means that they believe Global Warming could kill three quarters of the world's population in the next five years. And the media treats these people with total respect, and we skeptics are considered loony? It appears that the editors of the Canadian have taken NOAA climate research Steven Schneider at his word:
We have to offer up scary scenarios, make simplified, dramatic statements,
and make little mention of any doubts we have. Each of us has to decide what
the right balance is between being effective and being honest.
However, this example is a very good one to again raise the issue of the skeptical middle ground on climate.
The methane hydrate disaster case in this article may be extreme, but it is consistent in certain ways with the current climate theories of those who advocate various extreme warming scenarios that require massive government intervention (i.e. every climate study that the media chooses to report on). To oversimplify a bit, their warming models work in two parts:
- Man-made CO2 builds up in the atmosphere and acts to absorb more solar energy in the atmosphere than a similar atmospheric gas mix with less CO2 would. Most climate scientists agree that since CO2 only absorbs selected wavelengths, this a diminishing-return type effect. In other words, the second 10% increase in CO2 concentrations in the atmosphere has a smaller impact on global temperatures than the first 10%, and so on. Eventually, this effect becomes "saturated" such that all the wavelengths of sunlight that are going to be absorbed are absorbed, and further increases in CO2 concentration will have no further effect on world temperatures. No one knows where this saturation point is, but it might be as low as plus 2 degrees C, meaning the most we could raise global temperatures (without effects in part 2 below) is less than 2 degrees (assuming we have already seen some of this rise). By the way, though I think what I have just said fits the climate scientists' current "consensus," nothing in the italics part ever seems to get printed in the media.
- As temperatures rise worldwide due to warming from man-made CO2, other things in the climate will change. Hotter weather may cause more humidity from vaporized water, or more cloud cover, from the same effect. As posited in the article linked above, some methane hydrates in ice or in the ocean might vaporize due to higher temperatures. More plants or algae might grow in certain areas, less in others. All of these secondary effects might in turn further effect the global temperature. For example, more cloud cover might act to counter-act warming and cool things off. In turn, vaporizing methane hydrates would put more greenhouse gasses in the air that could accelerate warming.
Scientists typically call these secondary reactions feedback loops. Feedbacks that tend to counteract the initial direction of the process (e.g. warming creates clouds which then reduce warming) are called negative feedbacks. Feedbacks that tend to accelerate the process (warming vaporizes methane which causes more warming) are positive feedbacks. Negative feedback is a ball at the bottom of a valley that rolls back to its starting point when you nudge it; positive feedback is a ball perched on top of a mountain, where one slight nudge causes it to roll downhill faster and faster. Most natural processes are negative feedbacks -- otherwise nothing would be stable. In fact, while positive feedback processes are not unknown in nature, they are rare enough that most non-scientists would be hard-pressed to name one. The best one I can think of is nuclear fission and fusion, which should give you an idea of what happens when nature gets rolling on a positive feedback loop and why we wouldn't be around if there were many such processes.
So it is interesting that nearly every climate model that you hear of in the press assumes that the secondary effects from CO2-based warming are almost all positive, rather than negative feedbacks. Scientists, in a competition to see who can come up with the most dire model, have dreamed up numerous positive feedback effects and have mostly ignored any possible negative feedbacks. In other words, most climate scientists are currently hypothesizing that the world's climate is different from nearly every other natural process we know of and is one of the very very few runaway positive feedback processes in nature.
I want to offer up a couple of observations based on this state of affairs:
- Climate science is very hard and very chaotic, so there is nothing we really know with certainty. However, we have a far, far, far better understanding of #1 above than #2. In fact, models based just on effect #1 (without any feedbacks) do a decent job of explaining history (though they still overestimate actual warming some). However, models based on adding the positive feedback processes in #2 fail miserably at modeling history. (Several scientists have claimed to have "fixed" this by incorporating fudge factors, a practice many model-based financial market speculators have been bankrupted by). We have no real evidence yet to support any of the positive feedbacks, or even to support the hypothesis that the feedback is in fact positive rather than negative. I had a professor once who liked to make the lame joke that it was a bad "sign" if you did not even know if an effect was positive or negative.
- Because global warming advocates are much more comfortable arguing #1 than #2, they like to paint skeptics as all denying #1. This makes for a great straw man that is easy to beat, and is aided by the fact that there is a true minority who doesn't believe #1 (and who, despite everything that is written, have every right to continue to express that opinion without fear of reprisal). Actually, even better, they like to avoid defending their position at all and just argue that all skeptics are funded by Exxon.
- However, it is step #2 that is the key, and that we should be arguing about. Though the most extreme enviro-socialists just want to shut down growth and take over the world economy at any cost, most folks recognize that slowing warming with current technology represents a real trade-off between economic growth and CO2 output. And, most people recognize that reducing economic growth might be survivable in the rich countries like the US, but for countries like India and China, which are just starting to develop, slowing growth means locking hundreds of millions into poverty they finally have a chance to escape.
I am going to simplify this, but I think the following statement is pretty close: The warming from #1 alone (CO2 without positive feedbacks) will not be enough to justify the really harsh actions that would slow CO2 output enough to have any effect at all; only with substantial positive feedbacks from #2, such that the warming from CO2 alone is tripled, quadrupled or more (e.g. 8 degrees rather than 2) are warming forecasts dire enough to warrant substantial activity today.
So that is why I am a skeptic. I believe #1, though I know there are also things other than manmade CO2 causing some of the current warming (e.g. the sun's output is higher today than it has been in centuries). I do not think anyone has completed any really convincing work on #2, and Occam's razor tends to make me suspicious of hypothesizing positive feedback loops without evidence (since they are so much more rare than negative ones).
More on the skeptical middle ground here. Discussion of things like the "hockey stick" is here. For a small insight into how global warming advocates are knowingly exaggerating their case, see the footnote to this post.
Update: Increasingly, folks seem to want to equate "skeptic" with "denier." If so, I will have to change my terminology. However, that would be sad, as "skeptic" is a pretty good word. I accept there is some CO2 caused warming, but I am skeptical that the warming and its effects are as bad as folks like Al Gore make it out to be, and I am skeptical that the costs of an immediate lock-down on CO2 production will outweigh the benefits. That is why I call myself a skeptic. If that is now a bad term, someone needs to suggest a new one.
