NC Media Watch

A quest for reason and accuracy in letters to the editor, guest editorials and other issues of interest to the citizens of Western Nevada County.

Friday, March 25, 2005

Global Warming Update: Ice Cores.

Which came first? The CO2 or rising tempertures?
The ice cores from Vostock Antarctica have provided a recored of atmospheric gases and temperature proxies for over 400,000 years, extending over four intergalical periods.
There is a close correlation between Antarctic temperature and atmospheric concentrations of CO2 The extension of the Vostok CO2 record shows that the main trends of CO2 are similar for each glacial cycle. Major transitions from the lowest to the highest values are associated with glacial-interglacial transitions. During these transitions, the atmospheric concentrations of CO2 rises from 180 to 280-300 ppmv The extension of the Vostok CO2 record shows the present-day levels of CO2 are unprecedented during the past 420 kyr. Pre-industrial Holocene levels (~280 ppmv) are found during all interglacials, with the highest values (~300 ppmv) found approximately 323 kyr BP. When the Vostok ice core data were compared with other ice core data for the past 30,000 - 40,000 years, good agreement was found between the records: all show low CO2 values [~200 parts per million by volume (ppmv)] during the Last Glacial Maximum and increased atmospheric CO2 concentrations associated with the glacial-Holocene transition. These measurements indicate that, at the beginning of the deglaciations, the CO2 increase either was in phase or lagged by less than ~1000 years with respect to the Antarctic temperature, whereas it clearly lagged behind the temperature at the onset of the glaciations
Arctic and Antarctic Research Institute

vostock.jpg


If you look at the chart, it appear the highest concentrations of CO2 lagged the temperatrue rise by 400 to 600 years. What does that tell us about CO2 being the cause of rising global temperatures today?

Tell me what you think

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