Читать книгу Tropical Marine Ecology - Daniel M. Alongi - Страница 25

Mean atmospheric CO₂ concentrations will increase to 441 ppm over the 2081–2100 period (Church et al. 2013; Collins et al. 2013). This projected increase is the net result of complex atmospheric, land, and ocean forces. While tropical atmospheric CO₂ concentrations are rising, they respond to climatic events, such as El Niño. The tropical Pacific Ocean, for instance, plays an important role in modulating changes in atmospheric CO₂ concentrations during El Niño events. ENSO is correlated with large interannual variability in global atmospheric CO₂ concentrations. During the 2015–2016 ENSO event, there was a negative CO₂ change during the development phase (spring–summer 2015) which was likely due to a reduction in local CO₂ outgassing from the tropical Pacific Ocean; a positive CO₂ change was measured during the mature phase (autumn 2015–2016), likely a reflection of an increase in atmospheric CO₂ concentrations due to a combination of reduced vegetation uptake across pan‐tropical regions and enhanced biomass burning in Southeast Asia (Chatterjee et al. 2017). Thus, although atmospheric CO₂ levels are increasing, there are still notable variations and oscillations over time and space and probably explain some of the observed variability in pCO₂ concentrations in the world ocean.