Influence of El Nino on Atmospheric CO2 over the Tropical Pacific Ocean: Findings from NASA's OCO-2 Mission

Space-borne observations of CO2 from the Orbiting Carbon Observatory-2 are used to characterize the response of the tropical atmospheric CO2 concentrations to the strong El Nino event of 2015-2016. Correlations between atmospheric CO2 growth rate and the El Nino Southern Oscillation have been well known; however, the magnitude of the correlation and the timing of the responses of oceanic and terrestrial carbon cycle remain poorly constrained in space and time. Here we use space-based CO2 observations to confirm that the tropical Pacific Ocean does play an early and important role in modulating the changes in atmospheric CO2 concentrations during El Nino events phenomenon inferred but not previously observed due to lack of high-density, broad-scale CO2 observations over the Tropics