Methane and Carbon Dioxide Eddy-Covariance Flux Monitor

Methane (CH4), water vapor (H2O), and carbon dioxide (CO2) are collectively responsible for the majority of the Earth¿s greenhouse effect. Robust instrumentation that can measure these gases with both high accuracy and precision and with sufficient speed would reduce the uncertainty in the determination of terrestrial sources and sinks of these dominant greenhouse gases. Such knowledge is needed to improve predictive models that lead to a better understanding of the human contribution to global warming. The Phase I project built one prototype system. The prototype monitor met or exceeded all CO2 and CH4 performance targets as defined in the Phase I proposal, except for rise and fall times. The Phase II project will design, build, and fully test five analyzers able to produce continuous, high accuracy field measurements of ambient levels of atmospheric gases, at very high data rates, over years of operation in remote locations. Three analyzers will be sent to independent researchers as part of three performance and validation studies. One analyzer will be retained for long term software testing and validation, and the last analyzer will ultimately be destroyed during shock and vibration testing. Commercial Applications and other Benefits as described by the awardee: Government agencies around the world are already installing atmospheric monitoring stations. The Ameriflux network currently has 89 active stations in six countries. An improved CO2 and CH4 flux monitor deployed at these stations would provide high accuracy as well as high precision information at a data rate required for flux measurement. In addition, the analyzer requires far less calibration and sample preparation than currently available technology, leading to better reliability and reduced operating cost.