Ice sheet in West Antarctica existed 20 mn yrs earlier than believed
A new research has showed that an ice sheet located on West Antarctica existed 20 million years earlier than previously thought.
Washington: A new research has showed that an ice sheet located on West Antarctica existed 20 million years earlier than previously thought.
The findings indicate that ice sheets first grew on the West Antarctic subcontinent at the start of a global transition from warm greenhouse conditions to a cool icehouse climate 34 million years ago.
Previous computer simulations were unable to produce the amount of ice that geological records suggest existed at that time because neighbouring East Antarctica alone could not support it.
Earlier research published in 2009 and 2012 by the University of California, Santa Barbara, team showed that West Antarctica bedrock was much higher in elevation at the time of the global climate transition than it is today, with much of its land above sea level.
Lead author Douglas S. Wilson , a research geophysicist in UCSB`s Department of Earth Science and Marine Science Institute and his team used a sophisticated numerical ice sheet model to support this view.
Using their new bedrock elevation map for the Antarctic continent, the researchers created a computer simulation of the initiation of the Antarctic ice sheets.
Unlike previous computer simulations of Antarctic glaciation, this research found the nascent Antarctic ice sheet included substantial ice on the subcontinent of West Antarctica. The modern West Antarctic Ice Sheet contains about 10 percent of the total ice on Antarctica and is similar in scale to the Greenland Ice Sheet.
The findings have been published in Geophysical Research Letters, a journal of the American Geophysical Union.