Lightweight, High-Precision Instrument for Balloon Sonde CO2 Measurements

More accurate determination of CO2 in the atmosphere is required to reliably quantify the sources and sinks of carbon in the environment. However, current CO2 analytical instrumentation is relatively large and heavy, and requires significant amounts of electrical power to operate. As a result, in situ CO2 measurements must be recorded on weight-bearing vehicles (e.g., aircraft) that fly infrequently, thereby limiting the spatial and temporal resolution. This project will develop, test, and deploy a compact, inexpensive, low-power CO2 sensor (weight < 100 grams) capable of measuring CO2 while onboard balloon sondes over extended periods. The approach will be based on absorption spectroscopy techniques, which are capable of measuring CO2 with an uncertainty of less than 1 ppmv in the troposphere and tropopause. In Phase I, the CO2 sensor will be built; its durability and ruggedness will be tested over a range of temperatures, humidities, and pressures to simulate balloon conditions; its precision will be quantified using NIST-traceable standard gas mixtures; and an advanced prototype device for Phase II will be designed. The instrument will weigh about 100 grams and operate on a 9-volt battery. Commercial Applications And Other Benefits as described by the Applicant: The instrument should find commercial applications in atmospheric studies of carbon sources and sinks, industrial process control (chemical and petrochemical refineries), and pollution detection.