Climate Modelling
I read a lot about how we can't "prove" global warming using the scientific method. That's true. We can't experiment on the climate. There is, after all, only one Earth with only one atmosphere. That's where climate models come in. Models are very complex numerical representations of the climate. The more complex the model, the more computing power is needed to run it. They create, in effect, virtual Earths that modellers can experiment with.
Since climate modelling is so central to climate prediction, it only makes sense to stop and take a look at what climate models are and how they are developed and tested. The UK Met Office's Hadley Centre provides an overview of different types of climate models, from simple to complex.
Gavin Schmidt of NASA Goddard Institute for Space Studies has written an excellent, readable overview of the physics of climate modelling which briefly covers the history and development of climate models and explains the difference between weather forecasting models and climate models. Weather is chaotic, climate is stable.
Climate models are tested primarily with the present, particularly from 1979 on, when satellite data became readily available. Climate models, like weather forecasting models, seem to work best when taken as ensembles - the average seems better than any one whole - ironically, this is often the case with humans as weather forecasters as well.
Weather forecasting models have improved markedly in my 20 years as a meteorologist. I'm sure climate models have also had significant improvements in the last 20 years and will continue to improve in the future.
Comments (3)
The indoctrinated global meltdowners are always pointing to warming records to help push "The Theory". Here is more proof that the earth is getting warmer.
Mount Washington, NH - Throughout mid-January, New Hampshire experienced the coldest and most bitter conditions on record (from various sources, just Google it).
Uh, you might have a better arguement if record temperatures in North America were actually getting warmer, not colder. We have set many cold and snow records across the continent this year. Sorry, maybe next year will be more in your favor. I personnaly think that the hole in your "theory" is bigger than the hole in the ozone.
How many of you in the Global Warming Cult (Laura, no offensive intended, it's just a perspective) have changed your lifestyles to accomodate earth? Surely you are not all hypocrites and are all helping to make the world less warm, right? Have you changed? Has it made a difference? If humans are making the world warmer, than surely even if a small amount of people altering their lifestyles could make a small but noticable difference, right?
Congratualtions, I applaude all of you! Your sacrifice's have not gone unnoticed. Your group has collectively helped us to set new cold and snow records. Good job, but please be careful! Your inluence to help change the weather is very powerful, more powerful than mother nature herself. We don't want it to cold.
Posted by Rich | February 22, 2007 10:35 AM
Models can tell researchers how well they understand a particular complex system, but they often get misused when they are presented as 'proof' that something will occur.
This is why I instantly dismiss any global warming 'proof' that starts off with 'well, our computer models say...'. Its literally no different from reading palms or tea leaves. Computer models are, quite frankly, the prophesies of the global warming cult.
Posted by MG | February 22, 2007 3:03 PM
Computer models are also the foundation of economic models that predict the collapse of our economy if we regulate carbon. But you don't seem to have a problem citing these studies, MG.
These studies also predicted the collapse of our economy back in the 80s if we attempted to curb air pollution, water pollution, acid rain, and ozone depletion. Guess what? We've made great strides in those areas and the economy never collapsed.
And the economy will not collapse with carbon regulation either.
-Mark
Posted by Mark | February 24, 2007 3:47 PM