Friday, March 23, 2007

Biased Reporting or Confusion - Either Way It Says A Lot

Source: University of Copenhagen
Date: March 10, 2007

Climate Change: Could It Be Random?

Science Daily Severe climate changes during the last ice-age could have been caused by random chaotic variations on Earth and not governed by external periodic influences from the Sun. This has been shown in new calculations by a researcher at the Niels Bohr Institute, Copenhagen University.

The temperature curve through the Greenland inland ice sheet shows 26 dramatic and abrupt climate shifts during the last ice age that lasted more than 100.000 years. This curve shows the climate shifts during 40,000 years. The climate shifts appear to be periodic, but mathematical computer simulations shows that they are probably chaotic and random. (Credit: Peter Ditlevsen)

Several large international projects have succeeded in drilling ice-cores from the top of the Greenland inland ice through the more than 3 km thick ice sheet. The ice is a frozen archive of the climate of the past, which has been dated back all the way to the previous interglacial Eem-period more than 120.000 years ago.

The ice archive shows that the climate has experienced very severe changes during the glacial period. During the glacial period there were 26 abrupt temperature increases of about 7-10 degrees. These glacial warm periods are named Dansgaard-Oeschger events after the two scientists first observing them.

The global warming we experience presently will cause a temperature increase of perhaps 2-5 degrees in the next century if greenhouse gas emissions continue, researchers claim. This will lead to increased sea levels and more severe weather with terrible consequences. The temperature rise during the glacial period were much larger and happened much faster.


This is very important for understanding the cause of the climate changes and especially for predicting climate shifts. If they are random and chaotic they are fundamentally unpredictable.

Note: This story has been adapted from a news release issued by University of Copenhagen.

So, which is it? The entire article is about the possibility of randomness, yet the writer has to insert his own bias about the current climate change.

HT: Norma

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