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Talley, LD.  1984.  Meridional Heat-Transport in the Pacific-Ocean. Journal of Physical Oceanography. 14:231-241.   10.1175/1520-0485(1984)014<0231:mhtitp>;2   AbstractWebsite

The heat transported meridionally in the Pacific Ocean is calculated from the surface heat budgets of Clark and Weare and others; both budgets were based on Bunker's method with different radiation formulas. The meridional heat transport is also calculated from the surface heat budget of Esbensen and Kushnir, who used Budyko's method. The heat transport is southward at most latitudes if the numbers of Clark and of Weare are used. It is northward in the North Pacific and southward in the South Pacific if Eshensen and Kushnir's numbers are used. Systematic errors in both calculations appear to be so large that confident determination of even the sign of the heat transport in the North Pacific is not possible. The amount of heat transported poleward by all oceans is obtained from the Pacific Ocean calculation and transports in the Atlantic and Indian Oceans based on Bunker's surface heat fluxes.

Hernandez-Guerra, A, Talley LD.  2016.  Meridional overturning transports at 30 degrees S in the Indian and Pacific Oceans in 2002-2003 and 2009. Progress in Oceanography. 146:89-120.   10.1016/j.pocean.2016.06.005   AbstractWebsite

The meridional circulation and transports at 30 degrees S in the Pacific and Indian Oceans for the years 20022003 and 2009 are compared, using GO-SHIP hydrographic section data with an inverse box model and several choices of constraints. Southward heat transport across the combined Indian-Pacific sections, reflecting net heating north of these sections, doubled from -0.7 +/- 0.2 PW in 2002-2003 to -1.4 +/- 0.1 PW in 2009 (negative sign is southward), with the increase concentrated in the Indian Ocean (-0.6 PW compared with similar to 0.2 PW in the Pacific), and was insensitive to model choices for the Indonesian Throughflow. Diagnosed net evaporation also more than doubled in the Indian Ocean, from 0.21-0.27 Sv in 2002-2003 to 0.51-0.58 in 2009, with a smaller but significant increase in net evaporation in the Pacific, from 0.06-0.08 Sv to 0.16-0.32 Sv. These increased heat and freshwater exports coincided with Indian Ocean warming, a shift in the Indian's shallow gyre overturning transport to lower densities, and an increase in southward Agulhas Current transport from 75 Sv in 2002 to 92 Sv in 2009. The Indian's deep overturn weakened from about 11 Sv in 2002 to 7 Sv in 2009. In contrast, the Pacific Ocean overturning circulation was, nearly unchanged from 2003 to 2009, independent of model within the uncertainties. The East Australian Current transport decreased only slightly, from 52 Sv to 46 Sv. The southward Pacific Deep Water transport was at a higher density than the southward Indian Deep Water transport in both years and all models, similar to prior results. Estimated diapycnal diffusivity and velocity are strongly enhanced near the ocean bottom and are higher farther up in the water column in the Indian than in the Pacific, likely extending the reach of Indian Ocean overturning up to shallower depths than in the Pacific. The horizontal distribution of transports in the Pacific at all depths changed notably from 2003 to 2009, despite the stability of its meridional overturning structure. The 2009 horizontal structure resembles a "bowed gyre"; the hydrographic section data show that this disturbance extends to the abyss and disrupts the Deep Western Boundary Current structure in the Southwest Pacific Basin. Satellite altimetry suggests association with slow westward Rossby wave propagation generated in the eastern Pacific, with no apparent effect on the net overturning circulation. The Indian Ocean's upper ocean horizontal structure was stable between the two years even though its shallow gyre overturning transports changed significantly. On the other hand, northward abyssal transports concentrated' in the central Indian Ocean (Crozet Basin) in 2002 shifted westward to the Mozambique and Madagascar Basins in 2009, although the Crozet Basin's Deep Western Boundary Current existed in both years. (C) 2016 Elsevier Ltd. All rights reserved.

Russell, JL, Kamenkovich I, Bitz C, Ferrari R, Gille ST, Goodman PJ, Hallberg R, Johnson K, Khazmutdinova K, Marinov I, Mazloff M, Riser S, Sarmiento JL, Speer K, Talley LD, Wanninkhof R.  2018.  Metrics for the evaluation of the Southern Ocean in coupled climate models and earth system models. Journal of Geophysical Research-Oceans. 123:3120-3143.   10.1002/2017jc013461   AbstractWebsite

The Southern Ocean is central to the global climate and the global carbon cycle, and to the climate's response to increasing levels of atmospheric greenhouse gases, as it ventilates a large fraction of the global ocean volume. Global coupled climate models and earth system models, however, vary widely in their simulations of the Southern Ocean and its role in, and response to, the ongoing anthropogenic trend. Due to the region's complex water-mass structure and dynamics, Southern Ocean carbon and heat uptake depend on a combination of winds, eddies, mixing, buoyancy fluxes, and topography. Observationally based metrics are critical for discerning processes and mechanisms, and for validating and comparing climate and earth system models. New observations and understanding have allowed for progress in the creation of observationally based data/model metrics for the Southern Ocean. Metrics presented here provide a means to assess multiple simulations relative to the best available observations and observational products. Climate models that perform better according to these metrics also better simulate the uptake of heat and carbon by the Southern Ocean. This report is not strictly an intercomparison, but rather a distillation of key metrics that can reliably quantify the "accuracy" of a simulation against observed, or at least observable, quantities. One overall goal is to recommend standardization of observationally based benchmarks that the modeling community should aspire to meet in order to reduce uncertainties in climate projections, and especially uncertainties related to oceanic heat and carbon uptake. Plain Language Summary Observationally based metrics are essential for the standardized evaluation of climate and earth system models, and for reducing the uncertainty associated with future projections by those models.

Carter, BR, Talley LD, Dickson AG.  2014.  Mixing and remineralization in waters detrained from the surface into Subantarctic Mode Water and Antarctic Intermediate Water in the southeastern Pacific. Journal of Geophysical Research-Oceans. 119:4001-4028.   10.1002/2013jc009355   AbstractWebsite

A hydrographic data set collected in the region and season of Subantarctic Mode Water and Antarctic Intermediate Water (SAMW and AAIW) formation in the southeastern Pacific allows us to estimate the preformed properties of surface water detrained into these water masses from deep mixed layers north of the Subantarctic Front and Antarctic Surface Water south of the front. Using 10 measured seawater properties, we estimate: the fractions of SAMW/AAIW that originate as surface source waters, as well as fractions that mix into these water masses from subtropical thermocline water above and Upper Circumpolar Deep Water below the subducted SAMW/AAIW; ages associated with the detrained surface water; and remineralization and dissolution rates and ratios. The mixing patterns imply that cabbeling can account for similar to 0.005-0.03 kg m(-3) of additional density in AAIW, and similar to 0-0.02 kg m(-3) in SAMW. We estimate a shallow depth (similar to 300-700 m, above the aragonite saturation horizon) calcium carbonate dissolution rate of 0.4 +/- 0.2 mmol CaCO3 kg(-1) yr(-1), a phosphate remineralization rate of 0.031 +/- 0.009 mu mol P kg(-1) yr(-1), and remineralization ratios of P:N:-O-2:C-org of 1:(15.5 +/- 0.6):(143 +/- 10):(104 +/- 22) for SAMW/AAIW. Our shallow depth calcium carbonate dissolution rate is comparable to previous estimates for our region. Our -O-2:P ratio is smaller than many global averages. Our model suggests neglecting diapycnal mixing of preformed phosphate has likely biased previous estimates of -O-2:P and C-org:P high, but that the C-org:P ratio bias may have been counteracted by a second bias in previous studies from neglecting anthropogenic carbon gradients.

Hanawa, K, Talley LD.  2001.  Mode Waters. Ocean circulation and climate : observing and modelling the global ocean. ( Siedler G, Church J, Gould WJ, Eds.).:373-386., San Diego, Calif. London: Academic Abstract
Cronin, MF, Bond N, Booth J, Ichikawa H, Joyce TM, Kelly K, Kubota M, Qiu B, Reason C, Rouault M, Sabine C, Saino T, Small J, Suga T, Talley LD, Thompson LA, Weller RA.  2010.  Monitoring Ocean - Atmosphere Interactions in Western Boundary Current Extensions. Proceedings of OceanObs’09: Sustained Ocean Observations and Information for Society. 2( Hall J, Harrison DE, Stammer D, Eds.).   doi:10.5270/OceanObs09.cwp.20   Abstract