Sunday, December 21, 2008

Did we escape from a new Ice Age ?

Interesting news from Science Daily

Using three different climate models and removing the amount of greenhouse gases humans have injected into the atmosphere during the past 5,000 to 8,000 years, (Stephen) Vavrus and Kutzbach observed more permanent snow and ice cover in regions of Canada, Siberia, Greenland and the Rocky Mountains, all known to be seed regions for glaciers from previous ice ages. Vavrus notes: "With every feedback we've included, it seems to support the hypothesis (of a forestalled ice age) even more. We keep getting the same answer."

Another article published in 21st Century Science and Technology Magazine (2004) came up with this interesting data:

The geological requirements for an Ice Age are the presence of a large landmass around the Polar Circle and extending southward. A look at the globe, or world map, shows that those conditions exist in the Northern Hemisphere, but not in the Southern. Therefore, the important thing to look at is the climate conditions in northern and far northern regions. Some of the indicators:

• Since 1980, there has been an advance of more than 55% of the 625 mountain glaciers under observation by the World Glacier Monitoring group in Zurich. (From 1926 to 1960, some 70-95% of these glaciers were in retreat.)

• A comparison of the U.S. Department of Agriculture’s 1965 and 1990 Plant Hardiness Zone Maps, shows a southward change of one zone, or 10°F, between 1965 and 1990.

• Careful measurements of the oxygen isotope ratios in German oaks, which are rigorously calibrated to temperature data, show a 1°C temperature decline from 1350 to 1800 (the lowpoint of the Little Ice Age). Temperature thereafter increased by 1°C from 1800 to 1930, and has been declining since then.

• From weather stations in the Alps, and in the Nordic countries, we find the temperature decline since 1930 is also 1°C.

• Satellite measurements have shown growth in the height and breadth of the huge Greenland ice sheet, the largest in the Northern Hemisphere

Global warming a good thing? A bad thing? Global warming or cooling....one thing is sure....climate change as it is now called!

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