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Zhang, HM, Talley LD.  1998.  Heat and buoyancy budgets and mixing rates in the upper thermocline of the Indian and global oceans. Journal of Physical Oceanography. 28:1961-1978.   10.1175/1520-0485(1998)028<1961:habbam>;2   AbstractWebsite

Diapycnal and diathermal diffusivity values in the upper thermocline are estimated from buoyancy and heat budgets for water volumes bounded by isopycnals and isotherms, the air-sea interface, and coastline where applicable. Comprehensive analysis is given to the Indian Ocean, with an extended global general description. The Indian Ocean,gains buoyancy in the north (especially in the northeast) and loses buoyancy in the subtropical south. Freshest and least-dense water appears in the Bay of Bengal and isopycnals outcrop southwestward from there and then southward. Computation of diapycnal diffusivity (K-p) starts from the Bay of Bengal, expanding southwestward and southward and with depth. As isopycnals extend equatorward from the northeast and with increasing depth, K-p remains at about 1.3 cm(2) s(-1) for 20.2 sigma(theta) (Bay of Bengal) to 22.0 sigma(theta) (northeast Indian Ocean). Farther south (poleward) and at greater depth, K-p decreases from 0.9 cm(2) s(-1) for 23.0 sigma(theta) (north of 20 degrees S) to 0.5 cm(2) s(-1) for 25.0 sigma(theta) (north of 35 degrees S). Isotherms outcrop poleward from the equator. Diathermal diffusivity values computed from the heat budget are large at the equator and near the surface (4.0 cm(2) s(-1) for 28.5 degrees C isotherm) but decrease rapidly poleward and with depth (1.3 cm(2) s(-1) for 27.0 degrees C). This indicates stronger mixing either near the equator or the surface, or a possible component in the diathermal direction of the larger isopycnal diffusivity, as isotherms do not follow isopycnals in the upper Indian Ocean north of 10 degrees S. For the 21.0 degrees C isotherm? which closely follows isopycnal 25.0 sigma(theta), the heat budget yields a K-theta again of 0.5 cm(2) s(-1), the value of the diapycnal diffusivity. For the Indian-Pacific system, K-rho decreases from 1.3 cm(2) s(-1) for 22.0 sigma(theta) (the warm pool water, depth similar to 60 m) to 0.9 cm(2) s(-1) for 23.0 sigma(theta) (the tropical water between 20 degrees N and 20 degrees S, depth similar to 100 m), and to 0.1 cm(2) s(-1) for 25.0 sigma(theta) (40 degrees N-40 degrees S, depth similar to 170 m). In the eastern tropical Pacific, K-rho = 1.1 cm(2) s(-1) for 21.5 sigma(theta) (depth similar to 25 m) while K-rho = 0.6 cm(2) s(-1) for 22.0 sigma(theta) (depth similar to 35 m). In the Atlantic, K-rho = 0.6 cm(2) s(-1) for 24.0 sigma(theta) between 20 degrees N and 15 degrees S (depth similar to 80 m), and 0.2 cm(2) s(-1) for 25.0 sigma(theta) between 30 degrees N and 35 degrees S (depth similar to 120 m). For the water volume bounded by 25.5 sigma(theta) farther south and north (50 degrees N-40 degrees S), air-sea buoyancy gain in the Tropics is about the size of the buoyancy loss in the subtropics, and the near-zero net flux may not have significance compared to the errors in the data. For 27.5 sigma(theta), which encompasses the large region from about 65 degrees N to the Antarctic (with midocean average depth of 400 m), K-rho is 0.2 cm(2) s(-1). The results indicate that mixing strength generally decreases poleward and with depth in the upper ocean.

Bourassa, MA, Gille ST, Bitz C, Carlson D, Cerovecki I, Clayson CA, Cronin MF, Drennan WM, Fairall CW, Hoffman RN, Magnusdottir G, Pinker RT, Renfrew IA, Serreze M, Speer K, Talley LD, Wick GA.  2013.  High-latitude ocean and sea ice surface fluxes: Challenges for climate research. Bulletin of the American Meteorological Society. 94:403-423.   10.1175/bams-d-11-00244.1   AbstractWebsite

Polar regions have great sensitivity to climate forcing; however, understanding of the physical processes coupling the atmosphere and ocean in these regions is relatively poor. Improving our knowledge of high-latitute surface fluxes will require close collaboration among meteorologists, oceanographers, ice physicists, and climatologists, and between observationalists and modelers, as well as new combinations of in situ measurements and satellite remote sensing. This article describes the deficiencies in our current state of knowledge about air-sea surface fluxes in high latitutes, the sensitivity of various high-latitude processes to changes in surface fluxes, and the scientific requirements for surface fluxes at high latitutdes. We inventory the reasons, both logistical and physical, why existing flux products do not meet these requirements. Capturing an annual cycle in fluxes requires that instruments function through long periods of cold polar darkness, often far from support services, in situations subject to icing and extreme wave conditions. Furthermore, frequent cloud cover at high latitudes restricts the avilability of surface and atmospheric data from visible and infrared (IR) wavelength satellite sensors. Recommendations are made for improving high-latitude fluxes, including 1) acquiring more in situ observations, 2) developing improved satellite-flux-observing capabilities, 3) making observations and flux products more accessible, and 4) encouraging flux intercomparisons.

Talley, LD.  2007.  Hydrographic Atlas of the World Ocean Circulation Experiment (WOCE). Volume 2: Pacific Ocean. ( Sparrow M, Chapman P, Gould J, Eds.)., Southampton, UK: International WOCE Project Office Abstract


Talley, LD.  2013.  Hydrographic Atlas of the World Ocean Circulation Experiment (WOCE). Volume 4: Indian Ocean. ( and M. Sparrow CPJ, Ed.)., Southampton, U.K.: International WOCE Project Office
Fiedler, PC, Talley LD.  2006.  Hydrography of the eastern tropical Pacific: A review. Progress in Oceanography. 69:143-180.   10.1016/j.pocean.2006.03.008   AbstractWebsite

Eastern tropical Pacific Ocean waters lie at the eastern end of a basin-wide equatorial current system, between two large subtropical gyres and at the terminus of two eastern boundary currents. Descriptions and interpretations of surface, pycnocline, intermediate and deep waters in the region are reviewed. Spatial and temporal patterns are discussed using (1) maps of surface temperature, salinity, and nutrients (phosphate, silicate, nitrate and nitrite), and thermocline and mixed layer parameters, and (2) meridional and zonal sections of temperature, salinity, potential density, oxygen, and nutrients. These patterns were derived from World Ocean Database observations by an ocean interpolation algorithm: loess-weighted observations were projected onto quadratic functions of spatial coordinates while simultaneously fitting annual and semiannual harmonics and the Southern Oscillation Index to account for interannual variability. Contrasts between the equatorial cold tongue and the eastern Pacific warm pool are evident in all the hydrographic parameters. Annual cycles and ENSO (El Nino-Southern Oscillation) variability are of similar amplitude in the eastern tropical Pacific, however, there are important regional differences in relative variability at these time scales. Unique characteristics of the eastern tropical Pacific are discussed: the strong and shallow pycnocline, the pronounced oxygen minimum layer, and the Costa Rica Dome. This paper is part of a comprehensive review of the oceanography of the eastern tropical Pacific. (c) 2006 Elsevier Ltd. All rights reserved.