Increasing Causal Effects of El Nino-Southern Oscillation on the Future Carbon Cycle of Terrestrial Ecosystems

Here we examine the causal effects of El Nino-Southern Oscillation (ENSO) on the global carbon cycle over historical and future periods utilizing datasets from the Coupled Modeling Intercomparison Project Phase 6 models. Our results show that ENSO exhibits impact on terrestrial carbon fluxes and carbon storage over numerous regions of Asia, Oceania, and America. High consensus is found between models for the influences of ENSO over these regions. The results demonstrate that the effects of ENSO on carbon cycling over subtropics and high-latitude regions may be more significant than previously understood. In historical simulation, the regions affected by ENSO account for approximately 8.5% land-area and this proportion rises to approximately 11.7% in the future simulation, indicating an increase in ENSO influences on the gross primary productivity of terrestrial ecosystems. In addition, the results emphasize stronger response of seasonal carbon stocks to ENSO compared to that of seasonal carbon fluxes.

Automated summary

The study examines the causal effects of El Nino-Southern Oscillation (ENSO) on the global carbon cycle, showing significant impact on terrestrial carbon fluxes and storage in various regions. The influence of ENSO on carbon cycling in subtropics and high-latitude regions may be more significant than previously understood. Moreover, there is a stronger response of seasonal carbon stocks to ENSO compared to seasonal carbon fluxes.