HR: 0800h
AN: A11C-0600    [Abstracts]
TI: Observational evidence for long-term trends in carbon monoxide
AU: * Novelli, P C
EM: paul.c.novelli@noaa.gov
AF: NOAA/ESRL, 325 Broadway, Boulder, CO 80305, United States
AB: Changes in carbon monoxide (CO) have potentially important effects on the oxidizing capacity of the troposphere. It is commonly accepted that carbon monoxide (CO) in the Northern Hemisphere troposphere has increased significantly during the industrial era due to anthropogenic emissions. No significant trend has been determined in the Southern Hemisphere. CO is a product of fossil combustion and oxidation of CH4, both processes that have increased over the past century. The positive trend in CO is based on ice core studies, measurements of column abundances and surface time series. CO may no longer be increasing, measurements from a number of laboratories suggest CO mixing ratios have decreased over the past 20 years. This presentation will provide a re-examination of the data and evaluate the long-term trends in CO, focusing on issues that can affect trend analysis (such as short-term measurement periods and long-term calibration stability).
DE: 0345 Pollution: urban and regional (0305, 0478, 4251)
DE: 0365 Troposphere: composition and chemistry
DE: 0368 Troposphere: constituent transport and chemistry
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting