A little reminder - Atmospheric CO2 and its history

It is possible to core down through ancient ice deposits and determine what the level of CO2 was at the time that particular bit of ice froze. This is a no brainer. By looking at other gases dissolved in the ice, we can get a very accurate idea of the temperature at that time as well. What is prompting me to write this is that NASA's very own Dr. James Hanson lit off another one today, this time in the UK Guardian:

Coal-fired power stations are death factories. Close them
A year ago, I wrote to Gordon Brown asking him to place a moratorium on new coal-fired power plants in Britain. I have asked the same of Angela Merkel, Barack Obama, Kevin Rudd and other leaders. The reason is this - coal is the single greatest threat to civilisation and all life on our planet.

And he goes on and on and on... Another nugget:

The amount of carbon dioxide in the air has already risen to a dangerous level. The pre-industrial carbon dioxide amount was 280 parts per million (ppm). Humans, by burning coal, oil and gas, have increased this to 385 ppm; it continues to grow by about 2 ppm per year.

BZZZZZTTTTTT!!! Wrong! The pre-industrial CO2 level has fluctuated all over the map. It was around 280ppm for about the last million years or so but looking at the 800 million year record of data we have, this recent low level is an anomaly. The last time it was this low was 300 million years ago between the Carboniferous and the Permian eras. Wanna know what was happening then? Did you guess Ice Age? You got it right -- this was the second to last Ice Age that the Earth has been through; the last one ended about 10,000 years ago and we are (hopefully) still warming up from that one. Between these ice ages, the atmospheric CO2 has been as high as 6,000ppm (a lot more than the 280ppm that Hansen is bloviating about) and at that time, the average temperature was in the balmy 70's(F).

CO2 ≠ Anthropogenic Global Warming

For what prompted this rant, read the original Hanson editorial at the Guardian. Then read Anthony Watt's rebuttal. And one of Anthony's commentors left this wonderful snippet:

�� Every basket (of coal) is power and civilization. For coal is a portable climate� It carries the heat of the tropics to Labrador and the polar circle; and it is the means of transporting itself whithersoever it is wanted. Watt and Stephenson whispered in the ear of mankind their secret, that a half-ounce of coal will draw two tons a mile, and coal carries coal, by rail and by boat, to make Canada as warm as Calcutta, and with its comfort brings its industrial power.�
--Ralph Waldo Emerson

And another states the obvious:

If there were no coal trains and no coal-fired power stations, millions of people would have died this winter. Seems more like life trains than death trains.

And finally, Anthony referred to this post at Junk Science which explores the historical record I was talking about at the start of this post.

Planetary Temperature and Atmospheric Carbon Dioxide (CO2)
One point apparently causing confusion among our readers is the relative abundance of CO2 in the atmosphere today as compared with Earth's historical levels. Most people seem surprised when we say current levels are relatively low, at least from a long-term perspective - understandable considering the constant media/activist bleat about current levels being allegedly "catastrophically high." Even more express surprise that Earth is currently suffering one of its chilliest episodes in about six hundred million (600,000,000) years.

Given that the late Ordovician suffered an ice age (with associated mass extinction) while atmospheric CO2 levels were more than 4,000ppm higher than those of today (yes, that's a full order of magnitude higher), levels at which current 'guesstimations' of climate sensitivity to atmospheric CO2 suggest every last skerrick of ice should have been melted off the planet, we admit significant scepticism over simplistic claims of small increment in atmospheric CO2 equating to toasted planet. Granted, continental configuration now is nothing like it was then, Sol's irradiance differs, as do orbits, obliquity, etc., etc. but there is no obvious correlation between atmospheric CO2 and planetary temperature over the last 600 million years, so why would such relatively tiny amounts suddenly become a critical factor now?

What he said. Now, I am off to load some more firewood into the bin at the DaveCave(tm). Temperatures got down to 14 last night -- it is 33F outside right now so we are starting to come out of this abnormally hard winter. I could use some of that Global Warming right about now -- I can deal with high temperatures a lot better than low temperatures. Besides, as a Farmer, the extra CO2 will make my crops grow that much better...