WASHINGTON (CNN) -- Ice core samples from Antarctica suggest that the warming trend that ended an ice age 12,500 years ago may have overtaken the Earth in only a few decades -- raising concerns that the current warming trend may bring equally dramatic changes.

A University of Colorado team led by climatologist James White will publish their findings in the journal Science on Friday.

Previous research had shown a simultaneous but even greater increase in Arctic temperatures. Ice cores from Greenland, near the Arctic Circle, show a temperature increase of almost 59 degrees within a 50-year-period.

And White's team said the Antarctica ice cores show a temperature increase of about 20 degrees F within a few decades.

"What we see in Antarctica looks very, very similar to what we see in Greenland," said White. "We used to suspect that some of these big changes that occurred naturally in the past were only local. Since we see the same thing at opposite ends of the Earth, it does imply that the warming was a global phenomena."

He said the findings "throw a monkey wrench into paleo-climate research and rearrange our thinking about climate change at that time."

White said researchers need to look more closely at how the Earth's climate slipped from an ice age that ended about 12,500 years ago and shifted into the current, more temperate climate.

The findings, he said, also increases the urgency for researchers to understand climate shifts because it appears they could be abrupt and happen all over the Earth at roughly the same time.

"The challenge is to determine if a climate change will be a nice and gradual thing that we can adapt to, or will it be a mode shift that happens suddenly," said White.

The warming 12,500 years ago came within a typical human lifetime. Such rapid shifts in the climate on a global basis would make it very difficult for humans to adjust, he said. Climate affects agriculture, energy use, transportation and population shifts, and rapid changes would make adjustment in these things more difficult.

The Colorado researchers also found that the rapid temperature increases prompted huge releases of methane.

Methane is one of the principal gases responsible for the so-called greenhouse effect, in which gases like carbon dioxide and methane form a "blanket" around the Earth, entrapping solar heat and increasing land, water, and air temperatures. Methane is a by-product of the decay of plant matter.

Huge reserves of methane are trapped in frozen ground in the Arctic, and researchers have speculated that a rapid polar melting could release these trapped gases. Such methane releases would amplify the greenhouse effect.

The Intergovernmental Panel on Climate Change, a global group of over 2,000 climate scientists, estimated in 1995 that the world should expect temperature gains of 2 to 6 degrees by the year 2100, potentially causing dramatic changes in weather patterns, severe storm frequency, farm productivity, and enhancing the spread of tropical diseases.

Such a temperature rise would cause substantial melting of the polar ice caps and would cause warming ocean waters to expand, raising sea levels by up to 3 feet and obliterating low-lying lands.

The Colorado researchers' findings could suggest that the Earth is in line for larger, swifter temperature changes. The new research does not address how human activity could add to or impact climate change.

The cause of the apparently rapid change that ended the ice age is still largely unknown. A majority of climate scientists agree that industrialization could be accelerating the current warming trend.

But some scientists dispute the link between human activity -- primarily the use of fossil fuels -- and a steady increase in global temperatures. They say that current record temperatures are simply part of a centuries-long trend that is not a result of automobile and factory emissions.

White said that global warming caused by man-made greenhouse gases may be very similar to warming that may occur naturally.

"What humans are doing is in a way no different than what natural systems do," he said. "Humans add methane to the atmosphere. So does nature. We are simply doing it faster."

For this reason, said White, studying natural climate change of the past may give a fundamental understanding of how human actions could change the climate in the future.

The 15 warmest years on record have occurred since 1980, with 1998 on track for the highest average temperatures since record-keeping began twelve decades ago.

Accompanying papers to be published in Friday's Science explore the role of the oceans' currents in climate change. Columbia University researcher Mark Cane suggests that ocean current changes may also trigger long-term ice ages and warming trends, similar to the short-term changes that produce El Nino weather patterns.

The Associated Press contributed to this report.