Timescales of ventilation and consumption of oxygen and fixed nitrogen in the eastern tropical South Pacific oxygen deficient zone from transient tracers

Abstract The anthropogenic trace gases chlorofluorocarbon (CFC)-12 and sulfur hexafluoride (SF6) were measured during 2013 in the eastern tropical South Pacific Ocean (ETSP) offshore Chile and Peru (12°-22°S, 70°-86°W). Since the WOCE P21 line along ∼17°S in 1993, the CFC-12 penetration depth increased from ∼550 m to ∼800 m. In 2013, CFC-12 had penetrated through the bottom of the oxygen deficient zone (ODZ, where oxygen (O2)