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

[ACG49-04] The OCO-3 Mission: Performance of the Snapshot Area Map and Target Mode Observations and Coincident Measurements with the OMPS and TROPOMI Air Quality Sensors

*thomas p kurosu¹, Annmarie Eldering¹, Ralph basilio¹, matthew Bennett¹, Christopher O'Dell², Peter Somkuti², Thomas Taylor², Matthäus Kiel¹, Robert Nelson¹, Gary Spiers¹, Brendan Fisher¹, Ryan Pavlick¹, Gregory Osterman¹, Joshua Laughner³, Graziela Keller-Rodrigues¹, Shanshan Yu¹, David Crisp¹, Paul Wennberg³ (1.NASA Jet Propulsion Laboratory/California Institute of Technology, Pasadena, CA 91109, 2.Colorado State University, Fort Collins, CO 80523, 3.California Institute of Technology, Pasadena, CA 91125)

Keywords:Greenhouse Gas Monitoring, Carbon Cycle, International Space Station

The Orbiting Carbon Observatory 3 (OCO-3) was launched to the International Space Station (ISS) on 4 May 2019 and was successfully installed on 10 May 2019. First Light occurred in late June 2019, and the in-orbit check out of the instrument extended through July 2019. OCO-3 records reflected sunlight in the near-Infra Red spectral region to estimate the column average CO₂ dry air mole fraction (XCO₂) and solar-induced chlorophyll fluorescence (SIF). It complements the OCO-2 mission by employing a dedicated Snapshot Area Map (SAM) mode to map spatial areas of up to 80x80 km² on the Earth’s surface, including cities, volcanoes, and photosynthetically active surface types. The inclination of the ISS orbit limits OCO-3 to observations within +/- 52º latitude, but allows measurements at all times of day between sunrise and sunset to resolve diurnal variations in XCO₂ and SIF.

CO₂ emissions and air quality are closely linked, particularly over large urban agglomerates. OCO-3’s SAMs allows, for the first time, detailed studies of the relationship between CO₂ emissions and air quality tracers over megacities. Compared to CO₂, NO₂ is short-lived and can serve as indicator for temporally and locally enhanced fossil fuel emissions, as well as longer-term trends of urban development and growth.

We present the current status of the OCO-3 mission, with focus on SAM performance to identify anthropogenic CO₂ signals, and comparisons of OCO-3 SAM and Target Mode measurements of XCO₂ with NO₂ observations from NASA’s Ozone Monitoring and Profiler Suite on Suomi/NPP and JPSS-1 and ESA’s Sentinel-5 Precursor/TROPOMI. We present details on the performance of selected OCO-3 SAM and Target Mode observations, identify temporally and spatially near-coincident OMPS and TROPOMI measurements, and derive correlation statistics between CO₂ and the air quality tracers, with the aim to establish coincidence data record over the OCO-3 life time.