Thursday, January 15, 2004

Conceiving Of Climate As Moving Away From Equilibrium

Googling around while musing on connections between extreme weather and global warming, I discovered this enlightening interview with the director of the McGill Radar Observatory's Isztar Zawadzki, himself musing on extreme weather and global warming.
Will extreme weather increase because of global warming?

There is a good possibility that that will happen; fluctuations in the weather will likely be stronger. The global climate system is getting out of equilibrium and will undergo more variability before reaching a new equilibrium. Many elements in the system will be forced into a fast adjustment, and that will create oscillations in the weather.

How long will it take to reach a new equilibrium?

It could take 200 years, or 1,000 years. It depends on how fast everything can adjust to the new conditions. But species need time for evolution, for change. If the climate is changing too fast, there won't be time for a proper adjustment.

Is there a scientific consensus today about global warming?

We can say with certainty that global warming is happening; it is a fact. We have seen global warming for over a century now. With less certainty but still some confidence, we say that it's happening because of our own activities. There is still a debate on whether we are the cause, but there is a growing consensus that we are. Certainty stops at the level of global effects. At the regional level, the certainties drop even more. And when we talk about weather and extreme weather, we have zero certainties.

Knowing what we do today about developments in complexity and chaos theory, it is not fanciful or without ground to assert that climate change (i.e. global warming) could result in extreme weather (hotter and colder).

This seems counterintuitive mainly due to the choice of language (global warming in favor of climate change) and heuristic (underlying assumptions assuming linear shifts in climate rather than nonlinear transitions of a system moving away from equilibrium).