Constraining Sector-Specific CO2 Fluxes Using Space-Based XCO2 Observations Over the Los Angeles Basin

Summary/Abstract

The concentration of carbon dioxide (CO₂) in Earth’s atmosphere is increasing due to human activities and the resulting effects on the global climate system have initiated several policy-driven approaches to reduce emissions of this greenhouse gas. Quantifying the effectiveness of such policies requires both bottom-up and top-down approaches to estimate CO₂ emissions. This article investigates the amount of CO₂ emitted within the Los Angeles Basin between January 2020 and December 2021 using NASA’s Orbiting Carbon Observatory-3. The authors then use the observed CO₂ to assess contributions from specific sectors (on-road transportation, industrial sources, commercial maritime activity, etc.). The authors’ results demonstrate that urban CO₂ emissions observed from space-based instrumentation can be disaggregated to several socioeconomic sectors to study trends that may be present in each one. Notable detected features include the sudden reduction of on-road CO₂ emissions due to the COVID-19 lockdown period and the steady increase in off-shore emissions due to ship idling and delays.