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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


Book Chapter
Doney, SC, Ruckelshaus M, Duffy JE, Barry JP, Chan F, English CA, Galindo HM, Grebmeier JM, Hollowed AB, Knowlton N, Polovina J, Rabalais NN, Sydeman WJ, Talley LD.  2012.  Climate Change Impacts on Marine Ecosystems. Annual Review of Marine Science, Vol 4. 4( Carlson CA, Giovannoni SJ, Eds.).:11-37., Palo Alto: Annual Reviews   10.1146/annurev-marine-041911-111611   Abstract

In marine ecosystems, rising atmospheric CO2 and climate change are associated with concurrent shifts in temperature, circulation, stratification, nutrient input, oxygen content, and ocean acidification, with potentially wide-ranging biological effects. Population-level shifts are occurring because of physiological intolerance to new environments, altered dispersal patterns, and changes in species interactions. Together with local climate-driven invasion and extinction, these processes result in altered community structure and diversity, including possible emergence of novel ecosystems. Impacts are particularly striking for the poles and the tropics, because of the sensitivity of polar ecosystems to sea-ice retreat and poleward species migrations as well as the sensitivity of coral-algal symbiosis to minor increases in temperature. Midlatitude upwelling systems, like the California Current, exhibit strong linkages between climate and species distributions, phenology, and demography. Aggregated effects may modify energy and material flows as well as biogeochemical cycles, eventually impacting the overall ecosystem functioning and services upon which people and societies depend.

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
Bindoff, NL, Willebrand J, Artale V, Cazenave A, Gregory J, Gulev S, Hanawa K, Le Quere C, Levitus S, Nojiri Y, Shum CK, Talley LD, Unnikrishnan A.  2007.  Observations: Oceanic Climate Change and Sea Level. Climate change 2007 : the physical science basis : contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. ( Solomon S, Qin D, Manning M, Chen Z, Marquis M, Avery KB, Tignor M, Miller H, Eds.).:387-432., Cambridge ; New York: Cambridge University Press Abstract
Talley, LD, Stammer D, Fukumori I.  2001.  The WOCE Synthesis. Ocean circulation and climate : observing and modelling the global ocean. ( Siedler G, Church J, Gould WJ, Eds.).:525-546., San Diego, Calif. London: Academic Abstract
Journal Article
Gordon, AL, Ma SB, Olson DB, Hacker P, Ffield A, Talley LD, Wilson D, Baringer M.  1997.  Advection and diffusion of Indonesian throughflow water within the Indian Ocean South Equatorial Current. Geophysical Research Letters. 24:2573-2576.   10.1029/97gl01061   AbstractWebsite

Warm, low salinity Pacific water weaves through the Indonesian Seas into the eastern boundary of the Indian Ocean. The Indonesian Throughflow Water (ITW) adds freshwater into the Indian Ocean as it spreads by the advection and diffusion within the Indian Ocean's South Equatorial Current (SEC). The low salinity throughflow trace, centered along 12 degrees S, stretches across the Indian Ocean, separating the monsoon dominated regime of the northern Indian Ocean from the more typical subtropical stratification to the south. ITW is well represented within the SEC thermocline, extending with concentrations above 80% of initial characteristics from the sea surface to 300-m within the eastern half of the Indian Ocean, with 60% concentration reaching well into the western Indian Ocean. The ITW transport within the SEC varies from 4 to 12 x 10(6) m(3)sec(-1), partly in response to variations of the injection rate at the eastern boundary and to the likelihood of a zonally elongated recirculation cell between the Equatorial Counter Current and the SEC within the Indian Ocean. Lateral mixing disperses the ITW plume meridionally with an effective isopycnal mixing coefficient of 1.1 to 1.6 x 10(4) m(2)sec(-1).

Holte, J, Talley LD, Gilson J, Roemmich D.  2017.  An Argo mixed layer climatology and database. Geophysical Research Letters. 44:5618-5626.   10.1002/2017gl073426   AbstractWebsite

A global climatology and database of mixed layer properties are computed from nearly 1,250,000 Argo profiles. The climatology is calculated with both a hybrid algorithm for detecting the mixed layer depth (MLD) and a standard threshold method. The climatology provides accurate information about the depth, properties, extent, and seasonal patterns of global mixed layers. The individual profile results in the database can be used to construct time series of mixed layer properties in specific regions of interest. The climatology and database are available online at . The MLDs calculated by the hybrid algorithm are shallower and generally more accurate than those of the threshold method, particularly in regions of deep winter mixed layers; the new climatology differs the most from existing mixed layer climatologies in these regions. Examples are presented from the Labrador and Irminger Seas, the Southern Ocean, and the North Atlantic Ocean near the Gulf Stream. In these regions the threshold method tends to overestimate winter MLDs by approximately 10% compared to the algorithm.

Gray, AR, Johnson KS, Bushinsky SM, Riser SC, Russell JL, Talley LD, Wanninkhof R, Williams NL, Sarmiento JL.  2018.  Autonomous biogeochemical floats detect significant carbon dioxide outgassing in the high-latitude Southern Ocean. Geophysical Research Letters. 45:9049-9057.   10.1029/2018gl078013   AbstractWebsite

Although the Southern Ocean is thought to account for a significant portion of the contemporary oceanic uptake of carbon dioxide (CO2), flux estimates in this region are based on sparse observations that are strongly biased toward summer. Here we present new estimates of Southern Ocean air-sea CO2 fluxes calculated with measurements from biogeochemical profiling floats deployed by the Southern Ocean Carbon and Climate Observations and Modeling project during 2014-2017. Compared to ship-based CO2 flux estimates, the float-based fluxes find significantly stronger outgassing in the zone around Antarctica where carbon-rich deep waters upwell to the surface ocean. Although interannual variability contributes, this difference principally stems from the lack of autumn and winter ship-based observations in this high-latitude region. These results suggest that our current understanding of the distribution of oceanic CO2 sources and sinks may need revision and underscore the need for sustained year-round biogeochemical observations in the Southern Ocean. Plain Language Summary The Southern Ocean absorbs a great deal of carbon dioxide from the atmosphere and helps to shape the climate of Earth. However, we do not have many observations from this part of the world, especially in winter, because it is remote and inhospitable. Here we present new observations from robotic drifting buoys that take measurements of temperature, salinity, and other water properties year-round. We use these data to estimate the amount of carbon dioxide being absorbed by the Southern Ocean. In the open water region close to Antarctica, the new estimates are remarkably different from the previous estimates, which were based on data collected from ships. We discuss some possible reasons that the float-based estimate is different and how this changes our understanding of how the ocean absorbs carbon dioxide.

Williams, NL, Juranek LW, Feely RA, Johnson KS, Sarmiento JL, Talley LD, Dickson AG, Gray AR, Wanninkhof R, Russell JL, Riser SC, Takeshita Y.  2017.  Calculating surface ocean pCO(2) from biogeochemical Argo floats equipped with pH: An uncertainty analysis. Global Biogeochemical Cycles. 31:591-604.   10.1002/2016gb005541   AbstractWebsite

More than 74 biogeochemical profiling floats that measure water column pH, oxygen, nitrate, fluorescence, and backscattering at 10 day intervals have been deployed throughout the Southern Ocean. Calculating the surface ocean partial pressure of carbon dioxide (pCO(2sw)) from float pH has uncertainty contributions from the pH sensor, the alkalinity estimate, and carbonate system equilibrium constants, resulting in a relative standard uncertainty in pCO(2sw) of 2.7% (or 11 mu atm at pCO(2sw) of 400 mu atm). The calculated pCO(2sw) from several floats spanning a range of oceanographic regimes are compared to existing climatologies. In some locations, such as the subantarctic zone, the float data closely match the climatologies, but in the polar Antarctic zone significantly higher pCO(2sw) are calculated in the wintertime implying a greater air-sea CO2 efflux estimate. Our results based on four representative floats suggest that despite their uncertainty relative to direct measurements, the float data can be used to improve estimates for air-sea carbon flux, as well as to increase knowledge of spatial, seasonal, and interannual variability in this flux. Plain Language Summary The Southern Ocean is a key player in the global flow of carbon, yet it is hard to reach, and there are relatively few measurements there, especially in winter. Measuring the amount of carbon dioxide gas in seawater is key to advancing our understanding of the Southern Ocean. More than 74 robotic floats that use sensors to measure seawater properties have been deployed throughout the Southern Ocean, and each has a lifetime of around 5 years. It is currently not possible to directly measure carbon dioxide gas from these floats; however, it is possible to estimate carbon dioxide from things that the float can measure, like pH, a measure of ocean acidity. Here surface ocean carbon dioxide is estimated from several floats and compared to two ship-based estimates. In some locations, the floats closely match the existing estimates, but in other locations the floats see significantly higher surface ocean carbon dioxide in the wintertime, reinforcing the idea that the Southern Ocean's role in the global carbon cycle needs a closer look. Our results show that despite not measuring carbon dioxide directly, these floats will help scientists learn a lot about the Southern Ocean's part in the global flow of carbon.

Talley, LD, Feely RA, Sloyan BM, Wanninkhof R, Baringer MO, Bullister JL, Carlson CA, Doney SC, Fine RA, Firing E, Gruber N, Hansell DA, Ishii M, Johnson GC, Katsumata K, Key RM, Kramp M, Langdon C, Macdonald AM, Mathis JT, McDonagh EL, Mecking S, Millero FJ, Mordy CW, Nakano T, Sabine CL, Smethie WM, Swift JH, Tanhua T, Thurnherr AM, Warner MJ, Zhang J-Z.  2016.  Changes in Ocean Heat, Carbon Content, and Ventilation: A Review of the First Decade of GO-SHIP Global Repeat Hydrography. Annual Review of Marine Science. 8:185-215.   10.1146/annurev-marine-052915-100829   AbstractWebsite

Global ship-based programs, with highly accurate, full water column physical and biogeochemical observations repeated decadally since the 1970s, provide a crucial resource for documenting ocean change. The ocean, a central component of Earth's climate system, is taking up most of Earth's excess anthropogenic heat, with about 19% of this excess in the abyssal ocean beneath 2,000 m, dominated by Southern Ocean warming. The ocean also has taken up about 27% of anthropogenic carbon, resulting in acidification of the upper ocean. Increased stratification has resulted in a decline in oxygen and increase in nutrients in the Northern Hemisphere thermocline and an expansion of tropical oxygen minimum zones. Southern Hemisphere thermocline oxygen increased in the 2000s owing to stronger wind forcingand ventilation. The most recent decade of global hydrography has mapped dissolved organic carbon, a large, bioactive reservoir, for the first time and quantified its contribution to export production (∼20%) and deep-ocean oxygen utilization. Ship-based measurements also show that vertical diffusivity increases from a minimum in the thermocline to a maximum within the bottom 1,500 m, shifting our physical paradigm of the ocean's overturning circulation.

Marshall, J, Andersson A, Bates N, Dewar W, Doney S, Edson J, Ferrari R, Forget G, Fratantoni D, Gregg M, Joyce T, Kelly K, Lozier S, Lumpkin R, Maze G, Palter J, Samelson R, Silverthorne K, Skyllingstad E, Straneo F, Talley L, Thomas L, Toole J, Weller R, Climode G.  2009.  The CLIMODE FIELD CAMPAIGN Observing the Cycle of Convection and Restratification over the Gulf Stream. Bulletin of the American Meteorological Society. 90:1337-1350.   10.1175/2009bams2706.1   AbstractWebsite
Gladyshev, S, Talley L, Kantakov G, Khen G, Wakatsuchi M.  2003.  Distribution, formation, and seasonal variability of Okhotsk Sea Mode Water. Journal of Geophysical Research-Oceans. 108   10.1029/2001jc000877   AbstractWebsite

Russian historical data and recently completed conductivity-temperature-depth surveys are used to examine the formation and spread in the deep Ohkotsk Sea of dense shelf water (DSW) produced in the Okhotsk Sea polynyas. Isopycnal analysis indicates that all of the main polynyas contribute to the ventilation at sigma(theta) < 26.80, including the Okhotsk Sea Mode Water (OSMW), which has densities σ(θ) = 26.7-27.0. At densities greater than 26.9 σ(θ) the northwest polynya is the only contributor to OSMW. (Although Shelikhov Bay polynyas produce the densest water with σ(θ) > 27.1, vigorous tidal mixing leads to outflow of water with a density of only about 26.7 sigma(theta)). In the western Okhotsk Sea the East Sakhalin Current rapidly transports modified dense shelf water along the eastern Sakhalin slope to the Kuril Basin, where it is subject to further mixing because of the large anticyclonic eddies and tides. Most of the dense water flows off the shelves in spring. Their average flux does not exceed 0.2 Sv in summer and fall. The shelf water transport and water exchange with the North Pacific cause large seasonal variations of temperature at densities of 26.7-27.0 sigma(theta) (depths of 150-500 m) in the Kuril Basin, where the average temperature minimum occurs in April-May, and the average temperature maximum occurs in September, with a range of 0.2degrees-0.7degreesC. The average seasonal variations of salinity are quite small and do not exceed 0.05 psu. The Soya Water mixed by winter convection, penetrating to depths greater than 200 m, in the southern Kuril Basin also produces freezing water with density greater than 26.7 sigma(theta). Using a simple isopycnal box model and seasonal observations, the OSMW production rate is seen to increase in summer up to 2.2 +/- 1.7 Sv, mainly because of increased North Pacific inflow, and drops in winter to 0.2 +/- 0.1 Sv. A compensating decrease in temperature in the Kuril Basin implies a DSW volume transport of 1.4 +/- 1.1 Sv from February through May. The residence time of the OSMW in the Kuril Basin is 2 +/- 1.7 years.

Ogle, SE, Tamsitt V, Josey SA, Gille ST, Cerovecki I, Talley LD, Weller RA.  2018.  Episodic Southern Ocean heat loss and its mixed layer impacts revealed by the farthest south multiyear surface flux mooring. Geophysical Research Letters. 45:5002-5010.   10.1029/2017gl076909   AbstractWebsite

The Ocean Observatories Initiative air-sea flux mooring deployed at 54.08 degrees S, 89.67 degrees W, in the southeast Pacific sector of the Southern Ocean, is the farthest south long-term open ocean flux mooring ever deployed. Mooring observations (February 2015 to August 2017) provide the first in situ quantification of annual net air-sea heat exchange from one of the prime Subantarctic Mode Water formation regions. Episodic turbulent heat loss events (reaching a daily mean net flux of -294W/m(2)) generally occur when northeastward winds bring relatively cold, dry air to the mooring location, leading to large air-sea temperature and humidity differences. Wintertime heat loss events promote deep mixed layer formation that lead to Subantarctic Mode Water formation. However, these processes have strong interannual variability; a higher frequency of 2 sigma and 3 sigma turbulent heat loss events in winter 2015 led to deep mixed layers (>300m), which were nonexistent in winter 2016.

Waterhouse, AF, MacKinnon JA, Nash JD, Alford MH, Kunze E, Simmons HL, Polzin KL, St Laurent LC, Sun OM, Pinkel R, Talley LD, Whalen CB, Huussen TN, Carter GS, Fer I, Waterman S, Garabato ACN, Sanford TB, Lee CM.  2014.  Global patterns of diapycnal mixing from measurements of the turbulent dissipation rate. Journal of Physical Oceanography. 44:1854-1872.   10.1175/jpo-d-13-0104.1   AbstractWebsite

The authors present inferences of diapycnal diffusivity from a compilation of over 5200 microstructure profiles. As microstructure observations are sparse, these are supplemented with indirect measurements of mixing obtained from(i) Thorpe-scale overturns from moored profilers, a finescale parameterization applied to (ii) shipboard observations of upper-ocean shear, (iii) strain as measured by profiling floats, and (iv) shear and strain from full-depth lowered acoustic Doppler current profilers (LADCP) and CTD profiles. Vertical profiles of the turbulent dissipation rate are bottom enhanced over rough topography and abrupt, isolated ridges. The geography of depth-integrated dissipation rate shows spatial variability related to internal wave generation, suggesting one direct energy pathway to turbulence. The global-averaged diapycnal diffusivity below 1000-m depth is O(10(-4))m(2) s(-1) and above 1000-m depth is O(10(-5))m(2) s(-1). The compiled microstructure observations sample a wide range of internal wave power inputs and topographic roughness, providing a dataset with which to estimate a representative global-averaged dissipation rate and diffusivity. However, there is strong regional variability in the ratio between local internal wave generation and local dissipation. In some regions, the depth-integrated dissipation rate is comparable to the estimated power input into the local internal wave field. In a few cases, more internal wave power is dissipated than locally generated, suggesting remote internal wave sources. However, at most locations the total power lost through turbulent dissipation is less than the input into the local internal wave field. This suggests dissipation elsewhere, such as continental margins.

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.

Gordon, AL, Giulivi CF, Lee CM, Furey HH, Bower A, Talley L.  2002.  Japan/East Sea intrathermocline eddies. Journal of Physical Oceanography. 32:1960-1974.   10.1175/1520-0485(2002)032<1960:jesie>;2   AbstractWebsite

Intrathermocline eddies (ITE) with diameters of 100 km and of thickness greater than 100 m are observed within each of the three quasi-stationary meanders of the Tsushima Current of the Japan/East Sea. Within the ITE homogenous, anticyclonic flowing core, the temperature is near 10degreesC with a salinity of 34.12 psu. Because of compensatory baroclinicity of the upper and lower boundaries of the ITE core, the ITE has minor sea level expression. The ITE core displays positive oxygen and negative salinity anomalies in comparison to the surrounding thermocline water, indicative of formation from winter mixed layer water along the southern side of the Japan/East Sea subpolar front. The winter mixing layer is then overridden, or slips below, the regional upper thermocline stratification with its characteristic salinity maximum layer. The winter mixed layer off the coast of Korea closely matches the ITE core characteristics, and is considered as a potential source region. Other sources may be present along the southern boundary of the subpolar front, including a frequently observed warm eddy over the western side of Yamato Rise.

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.

Centurioni, LR, Hormann V, Talley LD, Arzeno I, Beal L, Caruso M, Conry P, Echols R, Fernando HJS, Giddings SN, Gordon A, Graber H, Harcourt RR, Jayne SR, Jensen TG, Lee CM, Lermusiaux PFJ, L'Hegaret P, Lucas AJ, Mahadevan A, McClean JL, Pawlak G, Rainville L, Riser SC, Seo H, Shcherbina AY, Skyllingstad E, Sprintall J, Subrahmanyam B, Terrill E, Todd RE, Trott C, Ulloa HN, Wang H.  2017.  Northern Arabian Sea Circulation Autonomous Research (NASCar): A research initiative based on autonomous sensors. Oceanography. 30:74-87.   10.5670/oceanog.2017.224   AbstractWebsite

The Arabian Sea circulation is forced by strong monsoonal winds and is characterized by vigorous seasonally reversing currents, extreme differences in sea surface salinity, localized substantial upwelling, and widespread submesoscale thermohaline structures. Its complicated sea surface temperature patterns are important for the onset and evolution of the Asian monsoon. This article describes a program that aims to elucidate the role of upper-ocean processes and atmospheric feedbacks in setting the sea surface temperature properties of the region. The wide range of spatial and temporal scales and the difficulty of accessing much of the region with ships due to piracy motivated a novel approach based on state-of-the-art autonomous ocean sensors and platforms. The extensive data set that is being collected, combined with numerical models and remote sensing data, confirms the role of planetary waves in the reversal of the Somali Current system. These data also document the fast response of the upper equatorial ocean to monsoon winds through changes in temperature and salinity and the connectivity of the surface currents across the northern Indian Ocean. New observations of thermohaline interleaving structures and mixing in setting the surface temperature properties of the northern Arabian Sea are also discussed.

Chamberlain, P, Talley LD, Mazloff M, Riser S, Speer K, Gray AR, Schwartzman A.  2018.  Observing the ice-covered Weddell Gyre with profiling floats: position uncertainties and correlation statistics. Journal of Geophysical Research: Oceans.   10.1029/2017JC012990   Abstract

Argo-type profiling floats do not receive satellite positioning while under sea ice. Common practice is to approximate unknown positions by linearly interpolating latitude-longitude between known positions before and after ice cover, although it has been suggested that some improvement may be obtained by interpolating along contours of planetary-geostrophic potential vorticity. Profiles with linearly interpolated positions represent 16% of the Southern Ocean Argo dataset; consequences arising from this approximation have not been quantified. Using three distinct datasets from the Weddell Gyre - 10 day satellite-tracked Argo floats, daily-tracked RAFOS-enabled floats, and a particle release simulation in the Southern Ocean State Estimate (SOSE) - we perform a data withholding experiment to assess position uncertainty in latitude-longitude and potential vorticity coordinates as a function of time since last fix. A spatial correlation analysis using the float data provides temperature and salinity uncertainty estimates as a function of distance error. Combining the spatial correlation scales and the position uncertainty, we estimate uncertainty in temperature and salinity as a function of duration of position loss. Maximum position uncertainty for interpolation during 8 months without position data is 116 ± 148 km for latitude-longitude and 92 ± 121 km for potential vorticity coordinates. The estimated maximum uncertainty in local temperature and salinity over the entire 2,000 m profiles during 8 months without position data is 0.66 ° C and 0.15 psu in the upper 300 m and 0.16 ° C and 0.01 psu below 300 m.

Roemmich, D, Alford MH, Claustre H, Johnson K, King B, Moum J, Oke P, Owens WB, Pouliquen S, Purkey S, Scanderbeg M, Suga T, Wijffels S, Zilberman N, Bakker D, Baringer M, Belbeoch M, Bittig HC, Boss E, Calil P, Carse F, Carval T, Chai F, Conchubhair DO, D'Ortenzio F, Dall'Olmo G, Desbruyeres D, Fennel K, Fer I, Ferrari R, Forget G, Freeland H, Fujiki T, Gehlen M, Greenan B, Hallberg R, Hibiya T, Hosoda S, Jayne S, Jochum M, Johnson GC, Kang K, Kolodziejczyk N, Kortzinger A, Le Traon PY, Lenn YD, Maze G, Mork KA, Morris T, Nagai T, Nash J, Garabato AN, Olsen A, Pattabhi RR, Prakash S, Riser S, Schmechtig C, Schmid C, Shroyer E, Sterl A, Sutton P, Talley L, Tanhua T, Thierry V, Thomalla S, Toole J, Troisi A, Trull TW, Turton J, Velez-Belchi PJ, Walczowski W, Wang HL, Wanninkhof R, Waterhouse AF, Waterman S, Watson A, Wilson C, Wong APS, Xu JP, Yasuda I.  2019.  On the future of Argo: A global, full-depth, multi-disciplinary array. Frontiers in Marine Science. 6   10.3389/fmars.2019.00439   AbstractWebsite

The Argo Program has been implemented and sustained for almost two decades, as a global array of about 4000 profiling floats. Argo provides continuous observations of ocean temperature and salinity versus pressure, from the sea surface to 2000 dbar. The successful installation of the Argo array and its innovative data management system arose opportunistically from the combination of great scientific need and technological innovation. Through the data system, Argo provides fundamental physical observations with broad societally-valuable applications, built on the cost-efficient and robust technologies of autonomous profiling floats. Following recent advances in platform and sensor technologies, even greater opportunity exists now than 20 years ago to (i) improve Argo's global coverage and value beyond the original design, (ii) extend Argo to span the full ocean depth, (iii) add biogeochemical sensors for improved understanding of oceanic cycles of carbon, nutrients, and ecosystems, and (iv) consider experimental sensors that might be included in the future, for example to document the spatial and temporal patterns of ocean mixing. For Core Argo and each of these enhancements, the past, present, and future progression along a path from experimental deployments to regional pilot arrays to global implementation is described. The objective is to create a fully global, top-to-bottom, dynamically complete, and multidisciplinary Argo Program that will integrate seamlessly with satellite and with other in situ elements of the Global Ocean Observing System (Legler et al., 2015). The integrated system will deliver operational reanalysis and forecasting capability, and assessment of the state and variability of the climate system with respect to physical, biogeochemical, and ecosystems parameters. It will enable basic research of unprecedented breadth and magnitude, and a wealth of ocean-education and outreach opportunities.

Carter, BR, Feely RA, Wanninkhof R, Kouketsu S, Sonnerup RE, Pardo PC, Sabine CL, Johnson GC, Sloyan BM, Murata A, Mecking S, Tilbrook B, Speer K, Talley LD, Millero FJ, Wijffels SE, Macdonald AM, Gruber N, Bullister JL.  2019.  Pacific anthropogenic carbon between 1991 and 2017. Global Biogeochemical Cycles. 33:597-617.   10.1029/2018gb006154   AbstractWebsite

We estimate anthropogenic carbon (C-anth) accumulation rates in the Pacific Ocean between 1991 and 2017 from 14 hydrographic sections that have been occupied two to four times over the past few decades, with most sections having been recently measured as part of the Global Ocean Ship-based Hydrographic Investigations Program. The rate of change of C-anth is estimated using a new method that combines the extended multiple linear regression method with improvements to address the challenges of analyzing multiple occupations of sections spaced irregularly in time. The C-anth accumulation rate over the top 1,500 m of the Pacific increased from 8.8 (+/- 1.1, 1 sigma) Pg of carbon per decade between 1995 and 2005 to 11.7 (+/- 1.1) PgC per decade between 2005 and 2015. For the entire Pacific, about half of this decadal increase in the accumulation rate is attributable to the increase in atmospheric CO2, while in the South Pacific subtropical gyre this fraction is closer to one fifth. This suggests a substantial enhancement of the accumulation of C-anth in the South Pacific by circulation variability and implies that a meaningful portion of the reinvigoration of the global CO2 sink that occurred between similar to 2000 and similar to 2010 could be driven by enhanced ocean C-anth uptake and advection into this gyre. Our assessment suggests that the accuracy of C-anth accumulation rate reconstructions along survey lines is limited by the accuracy of the full suite of hydrographic data and that a continuation of repeated surveys is a critical component of future carbon cycle monitoring.

Ruckelshaus, M, Doney SC, Galindo HM, Barry JP, Chan F, Duffy JE, English CA, Gaines SD, Grebmeier JM, Hollowed AB, Knowlton N, Polovina J, Rabalais NN, Sydeman WJ, Talley LD.  2013.  Securing ocean benefits for society in the face of climate change. Marine Policy. 40:154-159.   10.1016/j.marpol.2013.01.009   AbstractWebsite

Benefits humans rely on from the ocean - marine ecosystem services - are increasingly vulnerable under future climate. This paper reviews how three valued services have, and will continue to, shift under climate change: (1) capture fisheries, (2) food from aquaculture, and (3) protection from coastal hazards such as storms and sea-level rise. Climate adaptation planning is just beginning for fisheries, aquaculture production, and risk mitigation for coastal erosion and inundation. A few examples are highlighted, showing the promise of considering multiple ecosystem services in developing approaches to adapt to sea-level rise, ocean acidification, and rising sea temperatures. Ecosystem-based adaptation in fisheries and along coastlines and changes in aquaculture practices can improve resilience of species and habitats to future environmental challenges. Opportunities to use market incentives - such as compensation for services or nutrient trading schemes - are relatively untested in marine systems. Relocation of communities in response to rising sea levels illustrates the urgent need to manage human activities and investments in ecosystems to provide a sustainable flow of benefits in the face of future climate change. (C) 2013 Elsevier Ltd. All rights reserved.

Talley, LD, Rosso I, Kamenkovich I, Mazloff MR, Wang J, Boss E, Gray AR, Johnson KS, Key R, Riser SC, Williams NL, Sarmiento JL.  2018.  Southern Ocean biogeochemical float deployment strategy, with example from the Greenwich Meridian line (GO-SHIP A12). Journal of Geophysical Research: Oceans.   10.1029/2018JC014059   Abstract

Biogeochemical Argo floats, profiling to 2000 m depth, are being deployed throughout the Southern Ocean by the Southern Ocean Carbon and Climate Observations and Modeling program (SOCCOM). The goal is 200 floats by 2020, to provide the first full set of annual cycles of carbon, oxygen, nitrate and optical properties across multiple oceanographic regimes. Building from no prior coverage to a sparse array, deployments are based on prior knowledge of water mass properties, mean frontal locations, mean circulation and eddy variability, winds, air-sea heat/freshwater/carbon exchange, prior Argo trajectories, and float simulations in the Southern Ocean State Estimate (SOSE) and Hybrid Coordinate Ocean Model (HYCOM). Twelve floats deployed from the 2014-2015 Polarstern cruise from South Africa to Antarctica are used as a test case to evaluate the deployment strategy adopted for SOCCOM's 20 deployment cruises and 126 floats to date. After several years, these floats continue to represent the deployment zones targeted in advance: (1) Weddell Gyre sea ice zone, including the Antarctic Slope Front, Maud Rise, and the open gyre; (2) Antarctic Circumpolar Current (ACC) including the topographically-steered Southern zone ‘chimney' where upwelling carbon/nutrient-rich deep waters produce surprisingly large carbon dioxide outgassing; (3) Subantarctic and Subtropical zones between the ACC and Africa; and (4) Cape Basin. Argo floats and eddy-resolving HYCOM simulations were the best predictors of individual SOCCOM float pathways, with uncertainty after 2 years on the order of 1000 km in the sea ice zone and more than double that in and north of the ACC.

Talley, LD, Rosso I, Kamenkovich I, Mazloff MR, Wang J, Boss E, Gray AR, Johnson KS, Key RM, Riser SC, Williams NL, Sarmiento JL.  2019.  Southern Ocean biogeochemical float deployment strategy, with example from the Greenwich meridian line (GO-SHIP A12). Journal of Geophysical Research-Oceans. 124:403-431.   10.1029/2018jc014059   AbstractWebsite

Biogeochemical Argo floats, profiling to 2,000-m depth, are being deployed throughout the Southern Ocean by the Southern Ocean Carbon and Climate Observations and Modeling program (SOCCOM). The goal is 200 floats by 2020, to provide the first full set of annual cycles of carbon, oxygen, nitrate, and optical properties across multiple oceanographic regimes. Building from no prior coverage to a sparse array, deployments are based on prior knowledge of water mass properties, mean frontal locations, mean circulation and eddy variability, winds, air-sea heat/freshwater/carbon exchange, prior Argo trajectories, and float simulations in the Southern Ocean State Estimate and Hybrid Coordinate Ocean Model (HYCOM). Twelve floats deployed from the 2014-2015 Polarstern cruise from South Africa to Antarctica are used as a test case to evaluate the deployment strategy adopted for SOCCOM's 20 deployment cruises and 126 floats to date. After several years, these floats continue to represent the deployment zones targeted in advance: (1) Weddell Gyre sea ice zone, observing the Antarctic Slope Front, and a decadally-rare polynya over Maud Rise; (2) Antarctic Circumpolar Current (ACC) including the topographically steered Southern Zone chimney where upwelling carbon/nutrient-rich deep waters produce surprisingly large carbon dioxide outgassing; (3) Subantarctic and Subtropical zones between the ACC and Africa; and (4) Cape Basin. Argo floats and eddy-resolving HYCOM simulations were the best predictors of individual SOCCOM float pathways, with uncertainty after 2years of order 1,000km in the sea ice zone and more than double that in and north of the ACC.

Dong, S, Sprintall J, Gille ST, Talley L.  2008.  Southern Ocean mixed-layer depth from Argo float profiles. Journal of Geophysical Research-Oceans. 113   10.1029/2006jc004051   AbstractWebsite

Argo float profiles of temperature, salinity, and pressure are used to derive the mixed-layer depth (MLD) in the Southern Ocean. MLD is determined from individual profiles using both potential density and potential temperature criteria, and a monthly climatology is derived from individual MLDs using an objective mapping method. Quantitative data are available in the auxiliary material. The spatial structures of MLDs are similar in each month, with deep mixed layers within and just north of the Antarctic Circumpolar Current (ACC) in the Pacific and Indian oceans. The deepest mixed layers are found from June to October and are located just north of the ACC where Antarctic Intermediate Water (AAIW) and Subantarctic Mode Water ( SAMW) are formed. Examination of individual MLDs indicates that deep mixed layers ( MLD >= 400 m) from both the density and temperature criteria are concentrated in a narrow surface density band which is within the density range of SAMW. The surface salinity for these deep mixed layers associated with the SAMW formation are slightly fresher compared to historical estimates. Differences in air-sea heat exchanges, wind stress, and wind stress curl in the Pacific and Indian oceans suggest that the mode water formation in each ocean basin may be preconditioned by different processes. Wind mixing and Ekman transport of cold water from the south may assist the SAMW formation in the Indian Ocean. In the eastern Pacific, the formation of mode water is potentially preconditioned by the relative strong cooling and weak stratification from upwelling.