HR: 1340h
AN: B23A-0924    [Abstracts]
TI: Novel Instrumentation for Atmospheric Measurements of Carbon Dioxide and Stable Isotopes of Carbon Dioxide
AU: * Baer, D
EM: d.baer@LGRinc.com
AF: Los Gatos Research, 67 East Evelyn Avenue Suite 3, Mountain View, CA 94041
AU: Gupta, M
EM: m.gupta@LGRinc.com
AF: Los Gatos Research, 67 East Evelyn Avenue Suite 3, Mountain View, CA 94041
AU: Owano, T
EM: t.owano@LGRinc.com
AF: Los Gatos Research, 67 East Evelyn Avenue Suite 3, Mountain View, CA 94041
AU: Ricci, K
EM: k.ricci@LGRinc.com
AF: Los Gatos Research, 67 East Evelyn Avenue Suite 3, Mountain View, CA 94041
AU: O'Keefe, A
EM: a.okeefe@LGRinc.com
AF: Los Gatos Research, 67 East Evelyn Avenue Suite 3, Mountain View, CA 94041
AB: We present the development and testing of new compact, rugged and inexpensive instruments for measurements of carbon dioxide and stable isotopes of carbon dioxide in the atmosphere. These instruments, based on a new technology called Off-Axis Integrated Cavity Output Spectroscopy (Off-Axis ICOS), report measurements with high sensitivity, accuracy, and specificity in real time (no cross interferences). These instruments combine inexpensive, robust, and reliable room-temperature diode lasers operating in the near-infrared spectral region with Off-Axis ICOS, a patented and proven technology that provides extremely long optical paths (several thousand meters typical) to yield an instrument platform with important measurement capabilities. The first instrument reports measurements of carbon dioxide in air with a total uncertainty of less than 1 part in 3000. The second instrument reports measurements of the ratio of the isotopic abundances of 13CO2 and 12CO2 in ambient air with a precision of less than 0.2 del per mil. We will discuss the measurement strategies in detail and present recent results demonstrating real-time measurements without the need for any user intervention. Ongoing efforts to demonstrate the instrument's capabilities to record measurements with high accuracy and precision without calibration over extended periods as well as testing of the instrument at field sites in the AmeriFlux and FLUXNET networks, and NOAA/CMDL will also be discussed. By significantly increasing the accuracy and precision of carbon dioxide measurements in the field, these new instruments will significantly enhance studies of global warming and facilitate controlled multi-year studies and comparisons between geographically distant field sites. These studies will enable detailed monitoring of mass and energy exchange which is needed to determine the chemical composition of the atmosphere and the productivity of the biosphere. The instruments will thus help quantify in detail the global carbon cycle on local and large spatial scales and enable atmospheric chemists to generate reliable models of climate change.
UR: http://www.LGRinc.com
DE: 1094 Instruments and techniques
DE: 0315 Biosphere/atmosphere interactions
DE: 0365 Troposphere--composition and chemistry
DE: 0368 Troposphere--constituent transport and chemistry
DE: 0400 Biogeosciences
SC: Biogeosciences [B]
MN: 2004 AGU Fall Meeting