[A-CG49] Greenhouse Gas Monitoring from Space: Current Capabilities, Challenges, and Future Needs

[ACG49-05] Early Comparison of OCO-3 XCO2 Measurements with TCCON

*Matthäus Kiel¹、Joshua Laughner²、Annmarie Eldering¹、Brendan M. Fisher¹、thomas p kurosu¹、Ryan P. Pavlick¹、Gregory B. Osterman¹、Robert R. Nelson¹、Christopher W. O'Dell³、Peter Somkuti³、Thomas E. Taylor³、Coleen M. Roehl²、 TCCON Team (1.NASA Jet Propulsion Laboratory、2.Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA (USA)、3.Colorado State University, Fort Collins, CO (USA))

キーワード：CO2, International Space Station, Greenhouse Gas

The Orbiting Carbon Observatory-3 (OCO-3) was successfully launched on May 4, 2019 from Kennedy Space Center via a Space-X Falcon 9. One week later, the instrument was installed as an external payload on the International Space Station (ISS). OCO-3 extends NASA's study of carbon and measures the dry-air mole fraction of column carbon dioxide (XCO2) in the Earth’s atmosphere from space. These space-based measurements are compared to ground-based observations from the Total Carbon Column Observing Network (TCCON). TCCON is a global network of high-resolution ground-based Fourier Transform Spectrometers that records spectra of the sun in the near-infrared spectral region. From these spectra, accurate and precise column-averaged abundances of atmospheric constituents including CO2 are retrieved. TCCON data are tied to the WMO scale and serve as the link between calibrated surface in situ measurements and OCO-3 measurements. OCO-3’s agile 2-D pointing mirror assembly (PMA) allows the instrument to stare at a TCCON station as it passes overhead - providing information about the quality, biases, and errors in the OCO-3 data. Here, we show early comparisons between the OCO-3 XCO2 dataset collected during target mode observations and coincident TCCON measurements. Finally, we discuss site-dependent biases and its potential origins.