LI-COR Biosciences proposes to develop a new sensor that measures the concentration of carbon dioxide in the atmosphere with precision of 1 part in 3000 within one minute, requires only small amounts of gas, operates unattended in the field for at least 6 months, costs less than $5000, and is insensitive to motion. The sensor will advance a technology known as optical feedback cavity enhanced absorption spectroscopy (OF-CEAS). OF-CEAS can measure absorption more accurately than any other cavity enhanced absorption spectroscopy technique because the cavity delivers a much more intense signal beam to the photodetector and thereby enables an unparalleled signal-to-noise ratio (~10,000). OF-CEAS makes it possible to calculate the optical frequency of each measurement point with high accuracy by scanning the laser over a fixed grid of equidistant cavity modes. OF-CEAS makes it possible to reduce manufacturing costs in many ways: control the optical feedback by optimizing mirror reflectivities rather than incorporating a Faraday isolator, calculate the optical frequency of each cavity mode by taking advantage of the fixed grid of cavity modes rather than measuring optical frequency with an expensive wavelength monitor, incorporate small, relatively inexpensive mirrors into a small (~1 mL) cavity that requires only small quantities of calibration gases, employ relatively low-cost non-fiber-coupled lasers, and assemble instruments by mass production techniques. Increasing concentrations of carbon dioxide in the atmosphere are changing the earths climate. Climate change will cause extremely high daily temperatures, increase the frequency of heavy rainfall, intensify droughts, increase the maximum wind speed of cyclones, and cause sea levels to rise. The unavailability of low-cost, high-performance atmospheric CO2 sensors constrains the effort of environmental scientists to monitor CO2 at local, regional, and global scales. LI-COR Biosciences is introducing a new sensor technology that can measure carbon dioxide with state-of-the-art precision while reducing the price by a factor of 10. Commercial Applications: Scientists in university and government laboratory will apply the proposed sensors to measure carbon dioxide in the atmosphere. The sensors will help DOE to achieve its mission, which is to ensure Americas security and prosperity by addressing its energy, environmental, and nuclear challenges through transformative science and technology solutions. The proposed sensors will benefit the public by helping to provide a scientific basis for policies that mitigate the impacts of climate change.
