May 15, 2006
|Big-System Hysteresis||Environment Essays Peak Oil|
I've just started reading Elizabeth Kolbert's global warming book Field Notes From a Catastrophe (excellent so far), and I came across this arresting passage:
The effect of adding CO2 to the atmosphere is to throw the earth out of "energy balance." In order for the balance to be restored — as, according to the laws of physics, it eventually must be — the entire planet has to heat up, including the oceans, a process, [a panel of scientists from the National Academy of Sciences] noted, that could take "several decades." Thus, what might seem like the most conservative approach — waiting for evidence of warming to make sure the models were accurate — actually amounted to the riskiest possible strategy: "We may not be given a warning until the CO2 loading is such that an appreciable climate change is inevitable." [Emphasis added]
The fundamental problem is the scale of the Earth's global climate system. Because it's huge, it moves slowly. It has built-in time lags — what scientists and engineers call hysteresis — that mean that by the time global warming effects become pronounced the system is already in a critical phase. Effects are delayed, but when they begin, the transition to a new equilibrium is likely to be quite sudden. This is especially true of the climate system because of the suddenness of phase changes — e.g., ice to water.
It has taken a long time to get this enormous ocean liner moving on its current course, and it will take a long time to turn it around. The time to start easing off the throttle is long before the icebergs come into view. When Bush et al talk about the jury still being out on global warming and about the need to wait until it's obvious to everyone that the problem is serious and human activity is the cause (as if we don't know that already), he is like the captain of the Titanic, barreling full tilt through the icy North Atlantic. The downside of slowing down would have been nothing compared to the downside of hitting an iceberg and sinking. And we know how that turned out.
Roughly analogous considerations apply to peak oil. Many of the same people who downplay the seriousness and urgency of the global warming threat blithely assert that when oil gets scarce, rising prices will naturally prompt people to conserve and develop alternatives.
But again the problem is the scale of the system and its built-in time lags. Shrinking below-ground reserves don't cause oil prices to go higher. Prices depend on how much oil is coming out of the spigot. Prices won't go substantially higher until the below-ground situation has become so critical that oil can no longer be pumped out of the ground fast enough: i.e., price signals, when they come, will come too late. Switching to new energy technologies in transportation will take years, no matter what. The time to ease off the throttle is now. As with global warming, the seemingly conservative wait-and-see approach is actually the riskiest strategy possible. The cost of showing some self-restraint now will be nothing compared to the cost of letting the system crash.
Is it too late for prudence?
Does the rapidity of recent events suggest the effects of climate change are no longer lagging?
Storm season is getting off to an early start this year in the northern hemisphere...
Killer typhoon heads for China
Posted by: Jeff at May 16, 2006 01:47 PM