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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 PO4* 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 PO4* 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. [ABSTRACT FROM AUTHOR]

Just over 40 years ago, I wrote a paper entitled 'Climate change: Are we on the brink of a pronounced global warming?' In it, I attempted to explain why despite a rise in the atmosphere's CO2 content there had been no significant warming. I predicted that a natural cooling was about to give way to a warming, and that industrial emissions of CO2 would amplify this warming. The paper published in Science in 1975. Warming did follow in 1976-1977. However, a retrospective look shows that my analysis was flawed. What is more-and to my chagrin-based on the words 'global warming' in my Science paper, I was given the title 'Father of Global Warming.' Not only did I not like this title, I had done little to merit it. [ABSTRACT FROM AUTHOR]