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Fri, Jun 8, 2007

“The very powerful and the very stupid have one thing in common. Instead of altering their views to fit the facts, they alter the facts to fit their views…which can be very uncomfortable if you happen to be one of the facts that needs altering.”

—The Doctor.

It’s been a very spring, weather wise, in this part of Ontario, at least. It’s days like these where it’s hard to imagine anything wrong with the world. It’s days like these that enable us to ignore long term problems.

In the debate over the science behind the theory of global warming, one of the most frustrating things about it is that not much of the discussion is conducted by climate scientists, or even individuals who understand science. And this is a problem that exists on both sides. How else can we explain the rush by some believers to point to every hurricane, every warm day in January, and so on, as immediate evidence of global warming’s presence. It’s almost as frustrating as the rush by some sceptics to point to every normal day, every cold day in February, as immediate evidence that global warming doesn’t exist.

I’m not a scientist, and neither is Al Gore. David Susuki is a scientist, but I believe he is a geneticist, but we do have an idea of how science works. And the ongoing debate is ignoring this reality.

The science of the greenhouse effect is sound. We know that the greenhouse effect exists. The presence of carbon dioxide or methane or water vapour traps the sun’s heat in the atmosphere and prevents it from reflecting back out into space. It’s the reason why Venus has a higher average surface temperature than Mercury, even though Mercury is half the distance to the sun. Indeed, without the greenhouse effect, it’s doubtful that human civilization would exist. We need a balance of greenhouse gases in order to prevent the sun’s heat from simply bouncing off the surface of this planet and radiating out into space. This is basic physics and basic chemistry.

So we know which gases contribute to the effect, and from that we can deduce that sucking out carbon that has been removed from our environment for hundreds of millions of years and spewing it back into the atmosphere as carbon dioxide risks upsetting this balance. That’s basic math.

The problem is, most scientists will tell you that they don’t know exactly what the imbalance will do. The computer models suggest increased instability, and it’s not beyond the realm of imagination to suggest that a significant melt of our polar ice caps (which is happening) could eventually produce a real estate crisis in Florida, but it is frustrating seeing all of the people out there looking at isolated weather events as “evidence” which proves or disproves global warming, from the astoundingly stupendous, record-setting 2005 Atlantic Hurricane season as a proof of global warming’s existence, to the remarkably quiet 2006 Atlantic Hurricane season as proof of its non-existence (this was the result of La Nina, which kicked the activity to the western Pacific).

Don’t forget that the field of meteorology is the one that gave us chaos theory, precisely because the weather was proving to be so difficult to predict. Which puts scientists in a quandary. Consider: scientists have been quantifying the greenhouse effect for decades, now. They’ve identified the gases which contribute to it and it is reasonable for them and anybody who has followed their work to question the wisdom of dramatically adding carbon dioxide and methane to this system through human activity. It is reasonable to note that when more energy is added to a system, it becomes less stable. It is reasonable to point out how finely balanced our world’s environment is, and the potential consequences of knocking things out of balance. And from that it is reasonable to suggest that we should alter industry to burn less fuel or burn alternate fuels, and to use those fuels more efficiently.

However many individuals, from journalists to science fiction writers, to business interests possibly wishing to continue to externalize the costs of their greenhouse byproducts asked what is a reasonable question: “what does this mean?”

And most scientists will tell you, “We don’t know”.

And those who are predisposed to do nothing will respond, “oh, well, we don’t have to do anything, then.”

But a lack of predictive knowledge doesn’t discredit the science. Far from it. And it doesn’t discredit the question of whether or not it’s wise for us to be burning fossil fuels at the rate we’re burning them at (especially considering the finite supply). There is no doubt that we are risking making the system more unstable. And it is also true that alternatives exist, both now and in the future. And that there is an incentive, maybe not in the short term but definitely in the long term, to ensure that our economic growth is environmentally sustainable, so that we can truly guarantee that our children and grandchildren can continue to expect to live at our standard of living or better (a task complicated by the fact that the populations of China, India and Brazil might be striving to match that standard of living). To think otherwise is either short sightedness or laziness.

Scientists have made mistakes in the past. Indeed, mistakes are valued, as they too are tools that help in the furtherance of knowledge. But too many of us parrot the scientists, or downplay their findings, without doing much thinking of their own. Truthfully, they’re approaching the debate with their own minds made up, based on their own preconceived notions on the merits of the marketplace or the lack thereof. Not much will come of the discussion unless the rhetoric gets turned down and some minds get opened. Drop the hyperbole of the “proofs” and “disproofs” of global warming, note the uncertainties, but also really pay attention to the science, all the science, and not those few experiments that validate our own viewpoints.

Only then can we understand the problem and, ultimately, each other.

Global Cooling Does Not Disprove Global Warming

A favourite myth that self-professed climate change skeptics like to throw in the face of those who worry about climate change is the argument that “thirty years ago, we believed in Global Cooling”. This is rather disingenuous on a number of levels. This site here explains what was really going on at the time when some scientists predicted that an ice age was possible:

Firstly, there was a trend of cooling from the 40’s to the 70’s (although that needs to be qualified, as hemispheric or global temperature datasets were only just beginning to be assembled then). But people were well aware that extrapolating such a short trend was a mistake (Mason, 1976) . Secondly, it was becoming clear that ice ages followed a regular pattern and that interglacials (such as we are now in) were much shorter that the full glacial periods in between. Somehow this seems to have morphed (perhaps more in the popular mind than elsewhere) into the idea that the next ice age was predicatable and imminent. Thirdly, there were concerns about the relative magnitudes of aerosol forcing (cooling) and CO2 forcing (warming), although this latter strand seems to have been short lived.

The state of the science at the time (say, the mid 1970’s), based on reading the papers is, in summary: “…we do not have a good quantitative understanding of our climate machine and what determines its course. Without the fundamental understanding, it does not seem possible to predict climate…” (which is taken directly from NAS, 1975). In a bit more detail, people were aware of various forcing mechanisms - the ice age cycle; CO2 warming; aerosol cooling - but didn’t know which would be dominant in the near future. By the end of the 1970’s, though, it had become clear that CO2 warming would probably be dominant; that conclusion has subsequently strengthened.

I vaguely recall the idea expressed when I was in grade school that the world might be heading into an ice age, but I can also recall one key difference between that time and now. The sense was that the ice age was a natural occurrence, with the prediction based on trends as we’d measured them from various sources of geological evidence. The theory behind Global Warming suggests that human activity could be knocking our greenhouse gases out of balance.

The strike of “Global Cooling” is that it is supposedly antithetical to Global Warming; basically the skeptics are trying to say “well, thirty years ago you told us we were heading into a deep freeze, and now you say we’re going to boil. Which is it, huh? Huh?”

Well, they’re not antithetical. According to theory, Global Warming is the unnatural activity. Yes, scientists may have believed in Global Cooling thirty years ago, but that was seen as the Earth proceeding along its natural trends. Indeed it is a sign of the arrogance of some scientists in the fifties through the seventies that they were considering ways to stop the ice age, such as with solar reflectors in orbit, to thwart the natural procession of our heating and cooling cycle.

In other words, Global Cooling could still be a reality, thwarted by the unnatural release of carbon dioxide into the atmosphere. Therefore, saying scientists believed in Global Cooling does not in and of itself discredit scientists concerned about Global Warming.

On This Day

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