Description: Author Posting. © American Meteorological Society, 2007. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Atmospheric and Oceanic Technology 24 (2007): 1117-1130, doi:10.1175/JTECH2016.1.

Description: Sensor response corrections for two models of Sea-Bird Electronics, Inc., conductivity–temperature–depth (CTD) instruments (the SBE-41CP and SBE-41) designed for low-energy profiling applications were estimated and applied to oceanographic data. Three SBE-41CP CTDs mounted on prototype ice-tethered profilers deployed in the Arctic Ocean sampled diffusive thermohaline staircases and telemetered data to shore at their full 1-Hz resolution. Estimations of and corrections for finite thermistor time response, time shifts between when a parcel of water was sampled by the thermistor and when it was sampled by the conductivity cell, and the errors in salinity induced by the thermal inertia of the conductivity cell are developed with these data. In addition, thousands of profiles from Argo profiling floats equipped with SBE-41 CTDs were screened to select examples where thermally well-mixed surface layers overlaid strong thermoclines for which standard processing often yields spuriously fresh salinity estimates. Hundreds of profiles so identified are used to estimate and correct for the conductivity cell thermal mass error in SBE-41 CTDs.

Description: The National Ocean Partnership Program and the National Oceanic and Atmospheric Administration (NOAA) Office of Oceanic and Atmospheric Research funded this analysis. The ITP data were acquired under National Science Foundation (NSF) Grant OCE0324233.

Description: Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution September 1990

Description: Theory and observations of deep circulation in the near-equatorial Atlantic, Indian and Pacific Oceans are reviewed. Flow of deep and bottom water in the near-equatorial Indian and Pacific oceans, the two oceans with only a southern source of bottom water, is described through analysis of recent CTD data. Zero-velocity surfaces are chosen through use of water-mass properties and transports are estimated. Effects of basin geometry, bottom bathymetry and vertical diffusivity as well as a model meridional inertial current on a sloping bottom near the equator are all discussed in conjunction with the flow patterns inferred from observations. In the western equatorial Indian Ocean, repeat CTD surveys in the Somali Basin at the height of subsequent northeast and southwest monsoons show only small differences in the strength of the circulation of the bottom water (potential temperature θ ≤1.2°C). A deep western boundary current (DWBC) carrying about 4x106 m3 s-1 of this water is observed moving north along the continental rise of Africa at 3°S. The cross-equatorial sections suggest that the current turns eastward at the equator. The northern sections show a large mass of the coldest water in the interior east of the Chain Ridge, augmenting the evidence that the DWBC observed south of the equator turns east at the equator rather than remaining on the boundary, and feeds the interior circulation in the northern part of the basin from the equator. The circulation of deep water (1.2°C〈 θ ≤ 1.7°C) in the Somali and Arabian Basins is also analyzed. A DWBC flowing southward along the Carlsberg ridge in the Arabian Basin is described. In the central equatorial Pacific Ocean a recent zonal CTD section at 10°N, allows estimation that 5.0x106 m3 s-1 of Lower Circumpolar Water (LCPW, θ ≤ 1.2°C) moves northward as a DWBC along the Caroline Seamounts in the East Mariana Basin. In the Central Pacific Basin, 8.1x106 m3 s-1 of LCPW is estimated to move northward along the Marshal Seamounts as a DWBC at this latitude. An estimated 4.7x106 m3 s-1 of the LCPW moves back southward across 10°N in the Northeast Pacific Basin along the western flank of the East Pacific Rise and an equatorial jet is observed to flow westward from 138°W to 148°W shifting south of the Line Islands at 2.5°S, 159°W. The net northward flow of LCPW across 10°N in the Pacific Ocean is estimated at 8.4x106 m3 s-I. The net southward flow of the silica-rich North Pacific Deep Water (NPDW, 1.2 〈 θ ≤ 2.0°C) in the central Pacific Ocean estimated at 2.7x106 m3 s-1 is also discussed. In the Indian Ocean, the eastward equatorial flow in the the bottom water of the Somali Basin differs from the prediction of a flat-bottom uniform-upwelling Stommel-Arons calculation with realistic basin geometry and source location. The behavior of a uniform potential vorticity meridional jet on a sloping bottom is examined in an attempt to explain the observed behavior at the equator. The inertial jet does not cross the equator in a physically plausible fashion owing to the constraint of conservation of potential vorticity. Mass and heat budgets for the bottom water of the Somali Basin are of interest with respect to the equatorial feature. Upwelling through the θ = 1.2°C surface is estimated at 12±4x10-5 cm s-1 and a rough heat budget for the deep Somali Basin results in an estimate of vertical diffusivity of 9±5 cm2 s-1 at 3800 m. Numerical model results indicate that large vertical diffusivities result in eastward jets in the bottom water at the equator. In the Pacific Ocean the DWBC observed flowing northward south of the equator crosses the equator with transport nearly intact, albeit split into two at 10°N by the tortuous bathymetry. However the southward flow along the East Pacific Rise in the Northeast Pacific Basin and the westward equatorial jet this flow feeds are puzzling. The basin depth decreases equatorward and eastward, which may allow some southeastward flow in the Stommel-Arons framework. However, the equatorial jet is still unexplained. The estimated vertical velocity and diffusivity at 3600 db of 2±2x10-5 cm s-1 and 4±3 cm2 s-1 for the area between 12°8 and 10°N are much smaller than estimates in the Somali Basin. Thus the two oceans, similar in their single southern source of bottom water, have DWBC's which behave remarkably differently near the equator. In the Somali Basin of the Indian Ocean the DWBC appears to turn eastward at the equator, with large vertical upwelling velocity and large vertical diffusivity estimates for the bottom water of the basin. In the Pacific Ocean the DWBC appears to cross the equator, but there is a puzzling westward flowing equatorial jet in the bottom water of the Northeast Pacific Basin.

Description: The author began this research in the M.I.T.-W.H.O.I Joint Program while supported by the U. S. Offce of Naval Research through a Secretary of the Navy Graduate Fellowship in Oceanography. Support for collection and analysis of the data taken during R.R.S. Charles Darwin cruises 86-19 and 87-25 was provided by the U. S. National Science Foundation under grants OCE8800135 and OCE8513825 to D. B. Olson at the University of Miami and by the U. S. Offce of Naval Research under contract N00014-87-K-0001, NR083-004 and grant N00014-89-J-1076 to B. A. Warren at W.H.O.I. Collection of data taken during R.Y. Moana Wave cruise 89- 3 was supp6rted by the U. S. National Science Foundation under grant OCE881691O to H. L. Bryden and J. M. Toole at W.H.O.I. Collection of data taken during the U.S.-P.R.C. Toga cruises was supported by N.O.A.A. under grant NA85AA-DACU7.

Description: © The Author(s), 2019. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Roemmich, D., Alford, M. H., Claustre, H., Johnson, K., King, B., Moum, J., Oke, P., Owens, W. B., Pouliquen, S., Purkey, S., Scanderbeg, M., Suga, T., Wijffels, S., Zilberman, N., Bakker, D., Baringer, M., Belbeoch, M., Bittig, H. C., Boss, E., Calil, P., Carse, F., Carval, T., Chai, F., Conchubhair, D. O., 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, G. C., Kang, K., Kolodziejczyk, N., Kortzinger, A., Le Traon, P., Lenn, Y., Maze, G., Mork, K. A., Morris, T., Nagai, T., Nash, J., Garabato, A. N., Olsen, A., Pattabhi, R. R., 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, T. W., Turton, J., Velez-Belchi, P. J., Walczowski, W., Wang, H., Wanninkhof, R., Waterhouse, A. F., Waterman, S., Watson, A., Wilson, C., Wong, A. P. S., Xu, J., & Yasuda, I. On the future of Argo: A global, full-depth, multi-disciplinary array. Frontiers in Marine Science, 6, (2019): 439, doi:10.3389/fmars.2019.00439.

Description: 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.

Description: DR, MS, and NZ were supported by the US Argo Program through the NOAA Grant NA15OAR4320071 (CIMEC). WO, SJ, and SWi were supported by the US Argo Program through the NOAA Grant NA14OAR4320158 (CINAR). EuroArgo scientists were supported by the two grants: (1) AtlantOS funding by the European Union’s Horizon 2020 Research and Innovation Programme under the Grant Agreement No. 633211 and (2) Monitoring the Oceans and Climate Change with Argo (MOCCA) Co-funded by the European Maritime and Fisheries Fund (EMFF) Project No. SI2.709624. This manuscript represents a contribution to the following research projects for HC, CaS, and FD: remOcean (funded by the European Research Council, grant 246777), NAOS (funded by the Agence Nationale de la Recherche in the frame of the French “Equipement d’avenir” program, grant ANR J11R107-F), AtlantOS (funded by the European Union’s Horizon 2020 Research and Innovation Programme, grant 2014-633211), and the BGC-Argo project funded by the CNES. DB was funded by the EU RINGO project (730944 H2020-INFRADEV-2016-1). RF was supported by the AGS-1835576. GCJ was supported by the Global Ocean Monitoring and Observing Program, National Oceanic and Atmospheric Administration (NOAA), U.S., and the Department of Commerce and NOAA Research. LT was funded under the SOCCOM Grant No. NSF PLR-1425989. VT’s contribution was supported by the French National Research Agency (ANR) through the EQUIPEX NAOS (Novel Argo Observing System) under the reference ANR-10-EQPX-40 and by the European H2020 Research and Innovation Programme through the AtlantOS project under the reference 633211. WW was supported by the Argo Poland program through the Ministry of Sciences and Higher Education Grant No. DIR/WK/2016/12. AmW was funded by the NSF-OCE1434722. K-RK is funded by the National Institute of Meteorological Sciences’ Research and Development Program “Development of Marine Meteorology Monitoring and Next-generation Ocean Forecasting System” under the grant KMA2018-00421. CSchmid is funded by NOAA/AOML and the US Argo Program through NOAA/OOMD. MBa is funded by NOAA/AOML.