Wednesday, December 20, 2006

what models tell us: and what they don't

Sorry to disappoint but this post is about climate modelling and not an expose of Tyra Banks' latest exposition.

One of the problems with the politicisation of science is that projections, forecasts and guestimates produced by climate models are seized upon and exploited to suit whatever political policy directive its advocates cherish. This leads to a mis-construction of the science and a perpetuation of ecomyth fears: thus the claims that climate change will cause, and/or exacerbate, (insert flavour of the month fear here).

These statements make for great media copy, are easily reduced to simple headlines and a generally quite useful to those wishing to use scare tactics as a component of a wider political strategy to "save" the planet.

In general, climate models are limited by two things: the quality of the data, causal relationships and feedbacks built into the model (i.e. the model itself), and; the application of the model. It is this second point where the models reflect the ideology of those using them in that models are applied to today's problems and issues without regard to systemic changes outside of the modelled variables.
As this succinct discussion points out:
  1. climate change will likely prove unimportant to many of the phenomena identified by modellers as being impacted by climate change, and
  2. a global model of climate impacts has little chance of telling us what the biggest impacts will be.