Problems with ice core dating

Measuring the ratio of C14 to C12 and C13 therefore dates the organic matter for periods back to about eight half-lives of the isotope, 45,000 years.

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.

For example, the C14 concentration in the atmosphere depends upon cosmic ray intensity.

To take this into account, a calibration curve is developed using other dating methods to establish the C14 levels over time.

There are about two dozen decay pairs used for dating.

Uranium 235 decay to lead has a half-life of 713 million years, so it is well suited to dating the universe.

“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.

Scientists can study Earth’s climate as far back as 800,000 years by drilling core samples from deep underneath the ice sheets of Greenland and Antarctica.

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