HR: 13:40h
AN: U13B-01 INVITED     [Abstracts]
TI: The Mauna Loa Carbon Dioxide Record.
AU: * Tans, P P
EM: Pieter.Tans@noaa.gov
AF: NOAA, 325 Broadway, Boulder, CO 80305 United States
AB: Continuous measurements of atmospheric carbon dioxide were started in 1958 by Dave Keeling as part of the International Geophysical Year. Precision and accuracy were both high from the very beginning, facilitating after only a few years the unambiguous discovery of the seasonal cycle of CO2, as well as the year-to-year rise in concentration. Essential to the definitive nature of the Mauna Loa CO2 and similar records are the careful and continuing attention to calibration procedures, the creation of a calibration scale for CO2-in- air based on the determination of its mole fraction through primary methods, and the deployment of some "redundant" independent methods duplicating the CO2 measurements at several sites. The example of Mauna Loa demonstrated the principles that were incorporated into the design of later measurement networks that are now coordinated in the Global Atmosphere Watch Programme of the World Meteorological Organization. The high quality of the CO2 measurements allowed the later discoveries of the trends in the seasonal cycle, the trend in the gradient from north to south, and the relationship of the growth rate of CO2 to climate variations. The high quality is also the basis for all inverse modeling, which uses numerical models of atmospheric transport to translate quite small differences in space and time of the mole fraction of CO2 to deduce patterns of sources and sinks that are consistent with the observations. Some examples will be shown of the information that would be irretrievably lost if the high standards of these measurements are not maintained.
DE: 1610 Atmosphere (0315, 0325)
DE: 1615 Biogeochemical cycles, processes, and modeling (0412, 0414, 0793, 4805, 4912)
DE: 1694 Instruments and techniques
SC: Union [U]
MN: Fall Meeting 2005