11.27.2005
Rise in Gases Unmatched by a History in Ancient Ice (NYTimes.com)
By ANDREW C. REVKIN
Published: November 25, 2005
Shafts of ancient ice pulled from Antarctica's frozen depths show that for at least 650,000 years three important heat-trapping greenhouse gases never reached recent atmospheric levels caused by human activities, scientists are reporting today.
The measured gases were carbon dioxide, methane and nitrous oxide. Concentrations have risen over the last several centuries at a pace far beyond that seen before humans began intensively clearing forests and burning coal, oil and other fossil fuels.
The sampling and analysis were done by the European Program for Ice Coring in Antarctica, and the results are being published today in the journal Science.
The evidence was found in air bubbles trapped in successively older ice samples extracted from a nearly two-mile-deep hole drilled in a remote spot in East Antarctica called Dome C.
Experts familiar with the findings who were not involved with the research said the samples provided a vital long-term view of variations in the atmosphere and Antarctic climate. They say the data will help test and improve computer models used to forecast how accumulating greenhouse emissions will affect the climate.
Some climate experts not involved in the research said the findings also confirmed that the buildup of carbon dioxide and other heat-trapping smokestack and tailpipe emissions was taking the atmosphere into uncharted territory.
(More ... Rise in Gases Unmatched by a History in Ancient Ice - New York Times) ¶ 22:05
Published: November 25, 2005
Shafts of ancient ice pulled from Antarctica's frozen depths show that for at least 650,000 years three important heat-trapping greenhouse gases never reached recent atmospheric levels caused by human activities, scientists are reporting today.
The measured gases were carbon dioxide, methane and nitrous oxide. Concentrations have risen over the last several centuries at a pace far beyond that seen before humans began intensively clearing forests and burning coal, oil and other fossil fuels.
The sampling and analysis were done by the European Program for Ice Coring in Antarctica, and the results are being published today in the journal Science.
The evidence was found in air bubbles trapped in successively older ice samples extracted from a nearly two-mile-deep hole drilled in a remote spot in East Antarctica called Dome C.
Experts familiar with the findings who were not involved with the research said the samples provided a vital long-term view of variations in the atmosphere and Antarctic climate. They say the data will help test and improve computer models used to forecast how accumulating greenhouse emissions will affect the climate.
Some climate experts not involved in the research said the findings also confirmed that the buildup of carbon dioxide and other heat-trapping smokestack and tailpipe emissions was taking the atmosphere into uncharted territory.
(More ... Rise in Gases Unmatched by a History in Ancient Ice - New York Times) ¶ 22:05
