What fraction of the Pacific and Indian oceans' deep water is formed in the Southern Ocean?
2018
Abstract. In this contribution we explore constraints on the fractions of deep water
present in the Indian and Pacific oceans which originated in the northern
Atlantic and in the Southern Ocean. Based on PO 4 * we show that
if ventilated Antarctic shelf waters characterize the Southern contribution,
then the proportions could be close to 50–50. If instead a Southern Ocean
bottom water value is used, the Southern contribution is increased to
75 %. While this larger estimate may best characterize the volume of
water entering the Indo-Pacific from the Southern Ocean, it contains a
significant portion of entrained northern water. We also note that
ventilation may be highly tracer dependent: for instance Southern Ocean
waters may contribute only 35 % of the deep radiocarbon budget, even if
their volumetric contribution is 75 %. In our estimation, the most
promising approaches involve using CFC-11 to constrain the amount of deep
water formed in the Southern Ocean. Finally, we highlight the broad utility
of PO 4 * as a tracer of deep water masses, including descending
plumes of Antarctic Bottom Water and large-scale patterns of deep ocean
mixing, and as a tracer of the efficiency of the biological pump.
Keywords:
- Correction
- Source
- Cite
- Save
- Machine Reading By IdeaReader
45
References
9
Citations
NaN
KQI