5 September 2009
A major study on the Arctic temperatures was published this past week in SCIENCE. It’s gotten a lot of press attention, and a huge amount of attention in the Science world.
It’s not uncommon for those not familiar with the science to ask questions along the lines of “How can they possibly know what the temperature was 500 years ago! There were no thermometers!”
If science education were better in America, I (and others) would not hear this so often.
There were thermometers then. Not the kind we use today made of glass and mercury. Not the kind we use today made of electrical resistors and batteries. Anything that can measure temperature is a thermometer. Every measurement made in science with any kind of instrument, has error. There is no such thing as a perfectly accurate measurement! A physicist familiar with quantum dynamics can prove it to you, but I promise you it will leave your head hurting. Well, it did mine at least. Trust me, it gets real complicated when you get beyond Schroedinger’s cat!
Measurements made with a technique that imitates instruments we use today are very common in Science. The replacement instruments or techniques are called PROXIES. A common proxy for temperature and rainfall is tree rings. Tree ring proxies have been instrumental in discovering what happened to the peoples who lived in what is now Mesa Verde National Park in Colorado. It was climate that forced them out of the famous Cliff Palace 500 years ago.
How did scientists discover it?
They took sample of the wood the Indians used to build their cliff homes. They then compared the tree rings preserved in the cores, with a well developed tre ring record over the Southwest. They can tell you the exact year the Indians cut the tree, and also when the climate soured on them.
Darrell Kaufmann and several other well known paleo-climatologists have done the same thing to the Arctic using a variety of proxies for temperature. Their results were unfortunately, even worse than thought. The Climate of the Arctic has actually been cooling for most of the last 2000 years. We know why, too. Slow and steady changes in Earths orbit around the sun. These changes were first discovered by a Serbian named Milutin Milankovitch. This paper, is yet another confirmation, that our understanding of Earth’s climate has increased by an order of magnitude, (or more) in the last 30 years.
The really bad news is this. The Arctic has been rapidly warming for the last 100 years. This, of course, confirms the other measurements you have heard of, like the rapid loss of Arctic Sea ice, and the even more stunning drop in the thickness of what remains.
Even the most convinced scientist 25 years ago, would never have dared to predict the situation to be as bad, by the end of the first decade in the 21st century, as it has obviously become. This, in spite of the daily, and ever more silly claims, based on some rather amazing ignorance, to be found on junk science sites online.
There have been calls for a project matching the magnitude of the Manhattan Project, to deal with the planets climate problem. It’s looking now, like that would be a drop in the bucket. That kind of project is not likely to happen anyhow. Not as long as we live in the age of the silly.