@article {2644,
	title = {Upwelling in the Ocean Basins North of the ACC: 1. On the Upwelling Exposed by the Surface Distribution of C-14},
	journal = {Journal of Geophysical Research: Oceans},
	volume = {124},
	year = {2019},
	month = {Apr-04-2020},
	pages = {2591 - 2608},
	abstract = {he upwelling associated with the ocean{\textquoteright}s overturning circulation is hard to observe directly. Here, a large data set of surface C-14 measurements is compiled in order to show where deep water is brought back up to the surface in the ocean basins north of the Antarctic Circumpolar Current (ACC). Maps constructed from the data set show that low-C-14 deep water from the ACC is drawn up to the surface in or near the upwelling zones off Northwest Africa and Namibia in the Atlantic, off Costa Rica and Peru in the Pacific, and in the northern Arabian Sea in the Indian Ocean. Deep water also seems to be reaching the surface in the subarctic Pacific gyre near the Kamchatka Peninsula. The low-C-14 water drawn up to the surface in the upwelling zones is also shown to spread across the ocean basins. It is easily seen, for example, in the western Atlantic off Florida and in the western Pacific off New Guinea and Palau. The spreading allows one to estimate the volumes of upwelling, which, it turns out, are similar to the volumes of large-scale upwelling derived from inverse box models. This means that very large volumes of cool subsurface water are reaching the surface in and near the upwelling zonesmuch larger volumes than would be expected from the local winds.

Plain Language Summary The deep layers of the ocean are filled with cold dense water that sinks from the surface near Antarctica and in the northern North Atlantic. This process is understood reasonably well. The countervailing processthe way that the dense water is brought back up to the surfaceis not as well understood. Oceanographers now agree that the ocean{\textquoteright}s deep water is drawn back up to the surface (upwelled) mainly around Antarctica as part of the wind-driven overturning in the Antarctic Circumpolar Current (ACC). But cool water is also known to reach the surface in upwelling zones around the ocean{\textquoteright}s margins. Here we map the upwelling north of the ACC with the radioactive isotope carbon-14 and show that the deep water upwelled to the surface around Antarctica seems to be drawn up to the surface a second time in the upwelling zones. The water drawn up to the surface in the upwelling zones then flows back to the North Atlantic and sinks again to complete the cycle.},
	keywords = {Ocean circulation, overturning circulation, radiocarbon, Upwelling},
	issn = {2169-9275},
	doi = {10.1029/2018JC014794},
	url = {https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2018JC014794},
	author = {Toggweiler, J. R. and Druffel, Ellen R. M. and Key, Robert M. and Galbraith, Eric D.}
}
@article {2645,
	title = {Upwelling in the Ocean Basins North of the ACC: 2. How Cool Subantarctic Water Reaches the Surface in the Tropics},
	journal = {Journal of Geophysical Research: Oceans},
	volume = {124},
	year = {2019},
	month = {Apr-04-2020},
	pages = {2609 - 2625},
	abstract = {Large volumes of cool water are drawn up to the surface in the tropical oceans. A companion paper shows that the cool water reaches the surface in or near the upwelling zones off northern and southern Africa and Peru. The cool water has a subantarctic origin and spreads extensively across the Atlantic and Pacific basins after it reaches the surface. Here, we look at the spreading in two low-resolution ocean general circulation models and find that the spreading in the models is much less extensive than observed. The problem seems to be the way the upwelling and the spreading are connected (or not connected) to the ocean{\textquoteright}s large-scale overturning. As proposed here, the cool upwelling develops when warm buoyant water in the western tropics is drawn away to become deep water in the North Atlantic. The drawing away shoals the tropical thermocline in a way that allows cool subantarctic water to be drawn up to the surface along the eastern margins. The amounts of upwelling produced this way exceed the amounts generated by the winds in the upwelling zones by as much as 4 times. Flow restrictions make it difficult for the warm buoyant water in our models to be drawn away.

Plain Language Summary A companion paper uses the radioactive isotope carbon-14 to map the upwelling in the ocean basins north of the Antarctic Circumpolar Current (ACC). It shows that deep water drawn up to the surface to the south of the ACC is drawn up to the surface a second time in a number of upwelling areas in the tropics. In this paper, we attempt to simulate the tropical upwelling in an ocean circulation model and find that it is largely missing. Other circulation features are missing as well. The other features operate on the opposite sides of the ocean basins from the upwelling areas and help carry warm water out of the tropics (outflows). The combination of missing elements leads to a hypothesis about the upwelling mechanism. Our hypothesis is that the tropical upwelling is driven by the outflows and the fact that the warm water being carried away ultimately becomes deep water again in the North Atlantic.},
	keywords = {numerical modeling, Ocean circulation, overturning circulation, Upwelling},
	issn = {2169-9275},
	doi = {10.1029/2018JC014795},
	url = {https://www.researchgate.net/publication/331524382_Upwelling_in_the_Ocean_Basins_north_of_the_ACC_Part_1_On_the_Upwelling_Exposed_by_the_Surface_Distribution_of_D_14_C},
	author = {Toggweiler, J. R. and Druffel, Ellen R. M. and Key, Robert M. and Galbraith, Eric D.}
}
@article {149,
	title = {Radiocarbon Measurements in the Indian Ocean Aboard RVIB Nathaniel B. Palmer},
	journal = {Oceanography},
	volume = {25},
	year = {2012},
	note = {id: 2250; PT: J; TC: 0; SI: SI; UT: WOS:000308774600025},
	pages = {152-153},
	issn = {1042-8275},
	doi = {10.5670/oceanog.2012.89},
	author = {Key, Robert M. and McNichol, Ann}
}
@inbook {2426,
	title = {Natural Radiocarbon Distribution in the Deep Ocean},
	booktitle = {Global Environmental Change in the Ocean and on Land},
	volume = {Submitted},
	year = {2004},
	publisher = {Terrapub},
	organization = {Terrapub},
	isbn = {9784887041332},
	author = {Matsumoto, Katsumi  and Key, Robert M.},
	editor = {Shiyomi, M.}
}
@conference {1564,
	title = {The Antarctic Radiocarbon Storage Ring},
	booktitle = {8th International Conference on Accelerator Mass Spectrometry},
	year = {1999},
	note = {id: 1791},
	month = {1999},
	address = {Vienna, Austria},
	author = {Schneider, Robert J. and McNichol, Ann P. and von Reden, Karl F. and Elder, Kathryn L. and Gagnon, Alan R. and Key, Robert M. and Quay, Paul D.}
}
@article {2257,
	title = {A Correction for Aberrations in the Woods Hole Recombinator. Symposium of North-Eastern Accelerator Personnel},
	journal = {World Scientific},
	volume = {SNEAP 1996},
	year = {1998},
	note = {id: 1664},
	month = {1998},
	pages = {123-128},
	author = {Schneider, Robert J. and McNichol, Ann P. and von Reden, Karl F. and Elder, Kathryn L. and Gagnon, Allan R. and Key, Robert M. and Quay, Paul D.}
}
@conference {1620,
	title = {Early results from the WOCE radiocarbon program},
	booktitle = {TYKKI workshop invited talk},
	year = {1998},
	note = {id: 312},
	month = {1998},
	address = {Tokyo, Japan},
	author = {Key, Robert M.}
}
@conference {1769,
	title = {Radiocarbon in the North Pacific: What we have learned since GEOSECS},
	booktitle = {Seventh Annual PICES Meeting},
	year = {1998},
	note = {id: 311},
	month = {1998},
	address = {Fairbanks, AK},
	author = {Key, Robert M.}
}
@conference {1801,
	title = {Synthesis and modeling of the WOCE radiocarbon data set},
	booktitle = {WOCE Conference},
	year = {1998},
	note = {id: 1443},
	month = {1998},
	address = {Halifax, Canada},
	author = {Key, Robert M.}
}
