CO2 Levels Highest in 15 Million Years

CO2 Levels Not This High for 15 Million Years, When Climate Was 5° to 10°F Warmer and Seas Were 75 to 120 Feet Higher

~ “We have shown that this dramatic rise in sea level is associated with an increase in CO2 levels of about 100 ppm.” ~

You would have to go back at least 15 million years to find carbon dioxide levels on Earth as high as they are today, a UCLA scientist and colleagues report Oct. 8 in the online edition of the journal Science.

“The last time carbon dioxide levels were apparently as high as they are today — and were sustained at those levels — global temperatures were 5 to 10 degrees Fahrenheit higher than they are today, the sea level was approximately 75 to 120 feet higher than today, there was no permanent sea ice cap in the Arctic and very little ice on Antarctica and Greenland,” said the paper’s lead author, Aradhna Tripati, a UCLA assistant professor in the department of Earth and space sciences and the department of atmospheric and oceanic sciences.

“Carbon dioxide is a potent greenhouse gas, and geological observations that we now have for the last 20 million years lend strong support to the idea that carbon dioxide is an important agent for driving climate change throughout Earth’s history,” she said...

“A slightly shocking finding,” Tripati said, “is that the only time in the last 20 million years that we find evidence for carbon dioxide levels similar to the modern level of 387 parts per million was 15 to 20 million years ago, when the planet was dramatically different.”...

“We have shown that this dramatic rise in sea level is associated with an increase in carbon dioxide levels of about 100 parts per million, a huge change,” Tripati said. “This record is the first evidence that carbon dioxide may be linked with environmental changes, such as changes in the terrestrial ecosystem, distribution of ice, sea level and monsoon intensity.”

Today, the Arctic Ocean is covered with frozen ice all year long, an ice cap that has been there for about 14 million years.

“Prior to that, there was no permanent sea ice cap in the Arctic,” Tripati said...


for complete article:

Science: CO2 levels haven’t been this high for 15 million years, when it was 5° to 10°F warmer and seas were 75 to 120 feet higher — “We have shown that this dramatic rise in sea level is associated with an increase in CO2 levels of about 100 ppm.”

2009-10-18
http://climateprogress.org/2009/10/18/science-co2-levels-havent-been-this-high-for-15-million-years-when-it-was-5%C2%B0-to-10%C2%B0f-warmer-and-seas-were-75-to-120-feet-higher-we-have-shown-that-this-dramatic-rise-in-sea-level-i/#more-12516