High Accuracy Carbon Dioxide Analyzer

70173S02-II Studies of global warming require the monitoring and quantification of the global carbon cycle on large spatial scales, so that scientists can generate more reliable models of climate change. Significantly increased accuracy and precision of CO2 measurements are needed. This project will develop a compact, rugged, inexpensive instrument that uses telecommunications diode lasers to accurately and precisely measure CO2 concentrations in the atmosphere in real time. Phase I designed and built an Off-Axis Integrated Cavity Output Spectroscopy (ICOS) benchtop instrument that reports CO2 mixing ratio measurements in ambient air with improved accuracy and precision ( better than 1 part per 3000 in ?70 seconds), consumes less than 45 cubic centimeters of air per measurement, and requires no calibration or reference gases. Phase II will construct an instrument, suitable for commercial sale, that provides continuous CO2 mixing-ratio measurements with an overall accuracy of better than 1 part per 3000 in 30 seconds. The instrument will have an integrated microcontroller, operate unattended, and meet necessary manufacturing cost targets. The unit¿s inherent stability, ruggedness, and performance will be demonstrated in the field at several locations. Commercial Applications and Other Benefits as described by awardee: The instrument platform should have application to atmospheric studies, medical diagnostics to detect common diseases, the monitoring and control of chemical and petrochemical processes, petrochemical exploration, emissions monitoring, and engine testing and analysis.