Boron isotope constraints on deglacial deepwater formation and CO (sub 2) release from the North Pacific
Boron isotope constraints on deglacial deepwater formation and CO (sub 2) release from the North Pacific (in Goldschmidt 2012 abstract volume, Anonymous)
Mineralogical Magazine (2012) 76 (6): 2263
Deep convective mixing is thought to play a key role in glacial-interglacial cycles in atmospheric CO (sub 2) by providing a pathway for carbon between the deep ocean and the atmosphere. Such mixing is inhibited in the subpolar North Pacific by very low surface water salinity, and as a result the North Pacific is not typically thought to play a direct role in glacial-interglacial CO (sub 2) change. Here we challenge this assumption with new boron isotope and radiocarbon data, that track the behavior of carbon in the deep North Pacific over the last deglaciation. We show that over the last deglaciation deep water formed to 3600 m in the North Pacific. This is supported by experiments with an earth system model, which show that deep mixing in the North Pacific can account for a significant proportion of atmospheric CO (sub 2) rise during deglaciations.