Friday, March 5, 2010

Global Cooling

As Al Gore and others worry about the Earth turning into a raging inferno, I find this recent finding of Harvard scientists very interesting:
Geologists have found evidence that sea ice extended to the equator 716.5 million years ago, bringing new precision to a “snowball Earth” event long suspected of occurring around that time.

Led by scientists at Harvard, the team reports on its work in the latest edition of the journal Science . The new findings — based on an analysis of ancient tropical rocks in remote northwestern Canada — bolster the theory that the planet has, at times in the past, been covered with ice at all latitudes.

“This is the first time that the Sturtian glaciation [the name for that ice age] has been shown to have occurred at tropical latitudes, providing direct evidence that this particular glaciation was a ‘snowball Earth’ event,” said lead author Francis A. Macdonald, an assistant professor in Harvard's Department of Earth and Planetary Sciences. “Our data also suggests that the Sturtian glaciation lasted a minimum of 5 million years.”
I find it funny that climate modelers are so confident in their models despite the fact that the fundamental science, the unearthing of the basic facts of just how much or how little ice there was in the past, is still being uncovered. It is as if in 1890 a group of modelers clustered around their abacuses and debated exactly how much lift you would get out of a giant duck wing strapped to the back of a guy jumping off a cliff. The truth is, until the Wright brothers warped their wings to create lift, there was no science of "aerodynamics". I wonder how we can have a science of "climate modeling" when in fact we have not yet uncovered all the states of the earths climate in the past. Sure, the modelers can get some things right. But right enough to project "climate change" out for hundreds of years? What about the infamous Lorentz "butterfly effect" where a chaotic system is inherently unpredictable. In my mind, climate -- the field Lorenz was working in -- is the epitome of a chaotic system.

3 comments:

Unknown said...

I have argued with people in the past concerning the minor variations of our landscape that humans have made. Trees, buildings or the absence of these, I suggested, could change wind patterns and make small changes that might eventually make a bigger difference. So, as you say, there is no way to make a model that would be accurate even if the modeler could understand all of the past weather conditions and what caused them. But, I don't think they could ever understand all of the elements that came into play to make a snowball out of the earth or to melt that snow. When I was in high school chemistry, we had a project called the black box. The box had objects in it and the challenge was to come up with a theory of how many and what shape these objects were. The lesson was to show us how scientists had developed the theory of what an atom looks like, but I think the study of our planets distant past is much the same. They are looking at rocks and ice trying to come up with a reason or scenario. Their lack of understanding is evident every time they say something ending in a phrase like, "sooner than we expected".

RYviewpoint said...

Thomas: The next time you argue over human effects on the climate, point to Roger Pielke Sr. who has this blog site in which he frequently discusses how humans impact climate. His frustration with the IPCC is that they are focused too much on greenhouse gases and not enough on human environmental changes, or even the natural variation in climate.

Unknown said...

Thank you for the links.