This was described by Michael E. Mann,professor of meteorology at Penn State University. http://www.meteo.psu.edu/holocene/public_html/Mann/news/interviews.php Others have had readings that give similar results. "While scientists and environmentalists have used the daily milestone to highlight the buildup of greenhouse gases generated by human activities, it's the rate of rise that is most important. That rate, measured by the Keeling Curve, shows atmospheric CO2 levels are rising at unprecedented rates, driven largely by the burning of fossil fuels over the past two centuries. The curve, pioneered in 1958 by scientist Charles D. Keeling, is the longest-running tally of carbon dioxide levels in the atmosphere and is maintained by the Scripps Institution of Oceanography in San Diego. Readings there hit 399.46 Saturday. The weekly average reading at Mauna Loa was 399.52 last week, up nearly 22 points from a decade ago, according to the NOAA. Many scientists have warned that carbon dioxide readings must be brought down to 350 ppm to avoid severe climate impacts and stall "feedback loops" that will exacerbate the rise. Current ratios of carbon dioxide in the Earth's atmosphere remain at levels not seen in more than 3 million years, when sea levels were as much as 80 feet higher than current levels. For the previous 800,000 years, CO2 levels never exceeded 300 ppm, and there is no known geologic period in which rates of increase have been so sharp. The level was about 280 ppm at the advent of the Industrial Revolution in the 18th century, when the burning of fossil fuels began to soar." The Keeling curve data are taken in bottles of air samples daily at Mauna Loa, Hawaii by scientists from the UCal @San Diego and the CO2 analysis is made. The data are analyzed daily and report by week, month, 6 months, 1 year, 2 year, and 60 years, when the pioneered in 1958 by scientist Charles D. Keeling and is the longest-running tally of carbon dioxide levels in the atmosphere and is maintained by the Scripps Institution of Oceanography in San Diego. With this in mind (the Keeling Curve), the rate of rise is bound to be significantly effected by the expansion of the Alberta Tar Sands (Athabasca Tar Sands). This does not bode too well for us and the environment since the reserves are estimated to be at least 2 trillion barrels (worth trillions of dollars)! Any comments?