A runaway spurt of global
warming 55 million years ago turned Earth into a hothouse but how this
happened remains worryingly unclear, scientists said on Monday.
Previous
research into this period, called the Palaeocene-Eocene Thermal
Maximum, or PETM, estimates the planet's surface temperature blasted
upwards by between five and nine degrees Celsius (nine and 16.2 degrees
Fahrenheit) in just a few thousand years.
The Arctic Ocean warmed to 23 C (73 F), or about the temperature of a lukewarm bath.
How PETM happened is unclear but climatologists are eager to find out, as this could shed light on aspects of global warming today.
What seems clear is that a huge amount of heat-trapping "greenhouse"
gases -- natural, as opposed to man-made -- were disgorged in a very
short time.
More: http://www.physorg.com/news166715232.html