A committed fourfold increase in ocean oxygen loss

Abstract Less than a quarter of ocean deoxygenation that will ultimately be caused by historical CO 2 emissions is already realized, according to millennial-scale model simulations assume zero from year 2021 onwards. About 80% the committed oxygen loss occurs below 2000 m depth, where more sluggish overturning circulation increase water residence times and accumulation respiratory demand. According results, deep thereby lose 10% its pre-industrial content even if thus global warming were stopped today. In surface layer, however, ongoing largely stop once are stopped. Accounting for joint effects warming, metabolic viability representative marine animals declines up 25% over large regions ocean, posing an unavoidable escalation anthropogenic pressure on deep-ocean ecosystems.