Climate control: Tiny switches, big effects

Following on from Land Bridge Caused Wild Temperature Swings:

It is no surprise that some scientists seeking to develop better computer models that could help us understand and even forecast economic crises are turning to climate modellers for advice and inspiration. Modelling the global climate is as difficult and vexing a problem. You have got to take account of a lot of different factors all at once, not all the relevant processes are well understood, and little things can make a big difference.

Climate scientists have long realised that their computer models cannot be like those commonly used to simulate processes in, say, chemistry: one size doesn’t fit all as it often does (bar minor details) for chemical reactions, and your best bet is to come at the problem from many different angles and pool the findings.

It is for this reason that reporting the results of any climate modelling study is a delicate business. Any one study is typically best viewed not as a prediction of what the Earth’s climate system will definitely do under particular circumstances – without ice caps or the Amazon rainforest, say – but as an example of the range of possibilities. This type of fuzziness does not fit the common perception of science as providing precise answers, and it allows any sceptics who may not properly understand the scientific process to imply that climate models are just ill-informed guesswork.

Strait switch

All this is by way of saying that the striking conclusions of a modelling study of ocean circulation during an ice age should be seen primarily as an indication of how subtle geographic features can have unexpected, far-reaching impacts on climate.

More: http://www.bbc.com/future/story/20120413-climate-control-switches