Feb 15, 2017

Decline in global oceanic oxygen content during the past five decades

Sunke Schmidtko, Lothar Stramma, Martin Visbeck
  • Provides a quantitative assessment of the entire ocean oxygen inventory by analysing dissolved oxygen and supporting data for the complete oceanic water column over the past 50 years
  • Finds that the global oceanic oxygen content of 227.4 ± 1.1 petamoles (1015 mol) has decreased by more than two per cent (4.8 ± 2.1 petamoles) since 1960, with large variations in oxygen loss in different ocean basins and at different depths
  • Suggests that changes in the upper water column are mostly due to a warming-induced decrease in solubility and biological consumption
  • Finds that changes in the deeper ocean may have their origin in basin-scale multi-decadal variability, oceanic overturning slow-down and a potential increase in biological consumption