An Absolute C02 Monitor with Extremely High Accuracy

Carbon dioxide is monitored worldwide at hundreds of monitoring stations. However, existing methods rely on the use of high pressure calibration gas cylinders, which are both labor intensive and expensive. Thus, there is a pressing need for an affordable, highly accurate (at least 1 part in 3000) carbon dioxide monitor for the ambient atmosphere that can operate unattended for several months or more. This project will develop an absolute carbon dioxide monitor that will compare the absorbance of carbon dioxide in a sample cell to that in a permanently sealed quartz reference cell. The permanently sealed reference cell provides an absolute column density standard that will allow the instrument to measure mole fraction of carbon dioxide with an accuracy of 0.1 ppm (one part in 4000) during long term, unattended operation without the use of any consumables. Commercial Applications and other Benefits as described by the awardee: The instrument should be an attractive addition to the hundreds of carbon dioxide monitoring stations throughout the world, because it will run unattended and will not require frequent calibration. Improved measurements of CO2 would help us to better understand and mitigate global warming and global climate change.