Mankind's CO2 emissions may delay next ice age -- study

Human-driven climate change may have put the next ice age off by about 50,000 years, said scientists Thursday, highlighting our species' ever-more dominant influence on Earth's natural cycles.

Carbon dioxide (CO2) concentrations in the atmosphere could override other influences to make this the longest inter-ice age period in Earth history, they wrote in the journal Nature.

Without human influence, the next ice age was probably about 50,000 years away anyway, wrote the team led by Andrey Ganopolski of the Potsdam Institute for Climate Impact Research in Germany.

But current trends of CO2 emissions from humans burning oil, coal and gas, "are already sufficient to postpone the next ice age for another 50,000 years," he said.

"The bottom line is that we are basically skipping a whole glacial cycle, which is unprecedented."

Ice ages are caused partly by changes in Sun exposure caused by natural variations in the Earth's orbit, combined with the influence of planet-warming greenhouse gases in the atmosphere.

Temperate "interglacial" periods normally last about 20,000 to 30,000 years, according to scientists. Once every 400,000 years or so, an inter-ice age period will last longer than that.

The last ice age ended between 14,000 and 11,000 years ago, giving rise to the Holocene, Earth's current geological period, which has been an unusually mild inter-ice age era......http://www.bangkokpost.com/print/826492/
14/1/16