Problems with ice core dating Sexs chat albania
Current polar records show an intimate connection between atmospheric carbon dioxide and temperature in the natural world.
In essence, when one goes up, the other one follows.
“They say, ‘How could CO2 levels affect global temperature when you are telling me the temperature changed first?
’” Frédéric Parrenin of the Laboratory of Glaciology and Geophysical Environment in France and a team of researchers may have found an answer to the question.
However, two “dating details” negate this challenge.
The first dating detail exposes circular reasoning, which occurs when one assumes a particular outcome in arguing for that same outcome.
“The idea that there was a lag of CO2 behind temperature is something climate change skeptics pick on,” says Edward Brook of Oregon State University’s College of Earth, Ocean and Atmospheric Sciences.Thus, researchers usually “date” ice cores with theoretical models called “glacial flow models”—and these models assume evolutionary time.Counting layers sounds straightforward, but circular reasoning even shows up here.For example, secular scientists dated the Greenland GISP2 ice core by counting what they presumed were annual patterns of, among other features, dust, volcanics, isotopes, and ions in the ice.They assigned an “age” of about 85,000 years to the 2,800-meter depth back in 1994.