From: Phlip <phlip2005@...>
Date: 2009-04-22T22:35:09+09:00
Subject: Re: Goodbye Ruby - Hello Earth

Eleanor McHugh wrote:

> My main criticism of climate science's attempts to model global  
> warming is that it's fundamentally flawed in its methodology. The  
> climate is a chaotic non-linear system and hence the only way to make  
> accurate predictions is to understand its exact starting conditions.

The _weather_ is chaotic. The _climate_ is the walking average, beneath the 
turbulence. The point of the Butterfly Effect aphorism is you _can't_ predict 
whether the butterfly's wings flapping in Africa will create a hurricane in the 
Atlantic, even if you _did_ know how its wings flapped in microscopic detail.

However, you can predict trends over time, and you can predict the effect of 
forcing (such as more sunspots, or more CO2) on those trends. For example, 
Katrina occurred at the peak of a decadal cycle in hurricane activity. That 
doesn't mean CO2 didn't have a role...

> Instead researchers take patchy historical data over a brief  
> geological period and feed that into incredibly complex climate models  
> to produce predictions.

That's the prediction phase of the experiment. Then they confirm their 
predictions by correlating them to historical data, such as ice cores in 
glaciers containing the predicted amounts of certain chemicals at certain depths.

> Am I the only one reminded of Ptolemy's model of the heavens? A  
> stunning intellectual achievement, but as Copernicus demonstrated so  
> effectively, a complete fiction which prevented astronomy from  
> progressing for a good fourteen hundred years.

You have both the history and details wrong. Copernicus did not _demonstrate_ 
anything - he simply published the alternate view, which had already existed. 
And (the ghost of Carl Sagan notwithstanding), Ptolemaic models did not "prevent 
astronomy from progressing". You could still predict, over time, where Mars and 
Jupiter would appear in the skies. That's as old as Astrology.