ALBERT

Description: The deep ocean below 200 m water depth is the least observed, but largest habitat on our planet by volume and area. Over 150 years of exploration has revealed that this dynamic system provides critical climate regulation, houses a wealth of energy, mineral, and biological resources, and represents a vast repository of biological diversity. A long history of deep-ocean exploration and observation led to the initial concept for the Deep-Ocean Observing Strategy (DOOS), under the auspices of the Global Ocean Observing System (GOOS). Here we discuss the scientific need for globally integrated deep-ocean observing, its status, and the key scientific questions and societal mandates driving observing requirements over the next decade. We consider the Essential Ocean Variables (EOVs) needed to address deep-ocean challenges within the physical, biogeochemical, and biological/ecosystem sciences according to the Framework for Ocean Observing (FOO), and map these onto scientific questions. Opportunities for new and expanded synergies among deep-ocean stakeholders are discussed, including academic-industry partnerships with the oil and gas, mining, cable and fishing industries, the ocean exploration and mapping community, and biodiversity conservation initiatives. Future deep-ocean observing will benefit from the greater integration across traditional disciplines and sectors, achieved through demonstration projects and facilitated reuse and repurposing of existing deep-sea data efforts. We highlight examples of existing and emerging deep-sea methods and technologies, noting key challenges associated with data volume, preservation, standardization, and accessibility. Emerging technologies relevant to deep-ocean sustainability and the blue economy include novel genomics approaches, imaging technologies, and ultra-deep hydrographic measurements. Capacity building will be necessary to integrate capabilities into programs and projects at a global scale. Progress can be facilitated by Open Science and Findable, Accessible, Interoperable, Reusable (FAIR) data principles and converge on agreed to data standards, practices, vocabularies, and registries. We envision expansion of the deep-ocean observing community to embrace the participation of academia, industry, NGOs, national governments, international governmental organizations, and the public at large in order to unlock critical knowledge contained in the deep ocean over coming decades, and to realize the mutual benefits of thoughtful deep-ocean observing for all elements of a sustainable ocean.

Description: Climate change and variability are major societal challenges, and the ocean is an integral part of this complex and variable system. Key to the understanding of the ocean�s role in the Earth�s climate system is the study of ocean and sea-ice physical processes, including its interactions with the atmosphere, cryosphere, land, and biosphere. These processes include those linked to ocean circulation; the storage and redistribution of heat, carbon, salt and other water properties; and air-sea exchanges of heat, momentum, freshwater, carbon, and other gasses. Measurements of ocean physics variables are fundamental to reliable earth prediction systems for a range of applications and users. In addition, knowledge of the physical environment is fundamental to growing understanding of the ocean�s biogeochemistry and biological/ecosystem variability and function. Through the progress from OceanObs�99 to OceanObs�09, the ocean observing system has evolved from a platform centric perspective to an integrated observing system. The challenge now is for the observing system to evolve to respond to an increasingly diverse end user group. The Ocean Observations Physics and Climate panel (OOPC), formed in 1995, has undertaken many activities that led to observing system-related agreements. Here, OOPC will explore the opportunities and challenges for the development of a fit-for-purpose, sustained and prioritized ocean observing system, focusing on physical variables that maximize support for fundamental research, climate monitoring, forecasting on different timescales, and society. OOPC recommendations are guided by the Framework for Ocean Observing which emphasizes identifying user requirements by considering time and space scales of the Essential Ocean Variables. This approach provides a framework for reviewing the adequacy of the observing system, looking for synergies in delivering an integrated observing system for a range of applications and focusing innovation in areas where existing technologies do not meet these requirements.

Description: The Arabian Sea is strongly forced by monsoon winds. Surface moorings deployed in the Arabian Sea are exposed to high winds and large waves. The waves, generated by strong wind events, impose a dynamic load on all mooring components. The dynamic cycling of mooring components can be so severe that ultimate strength considerations are superseded by the fatigue properties of the standard hardware components. Concerns about all in-line mooring components and their fatigue endurance dictated the need for an independent series of cyclic fatigue tests. The components tested included shackles of various sizes and configurations, wire rope, instrument cages, chain, and a variety of interconnecting links such as weldless sling links and end links. The information gained from these tests was used in the design of the surface moorings deployed in the Arabian Sea by the Upper Ocean Processes group of the Woods Hole Oceanographic Institution. The results of the cyclic fatigue tests conducted in support of the Arabian Sea surface mooring design effort are presented in this report. Recommendations are made with regard to all in-line components for surface moorings where dynamic conditions might be encountered for extended periods. The fatigue test results from shackles, and sling links were compiled to generate an SIN diagram where the cyclic stress amplitude is plotted versus the number of cycles to failure. In addition, the wire rope test results were compiled with historical wire rope data from US steel to generate a SIN diagram for torque balanced 3x19 wire rope. These results can be used in conjunction with future design efforts.

Description: Funding was provided by the Office of Naval Research through Grant No. N00014-94-1-0161.

Description: Author Posting. © Sears Foundation for Marine Research, 2006. This article is posted here by permission of Sears Foundation for Marine Research for personal use, not for redistribution. The definitive version was published in Journal of Marine Research 64 (2006): 745-758, doi:10.1357/002224006779367285.

Description: Mixed layer depth (MLD) is an important oceanographic parameter. However, the lack of direct observations of MLD hampers both specification and investigation of its spatial and temporal variability. An important alternative to direct observation would be the ability to estimate MLD from surface parameters easily available from satellites. In this study, we demonstrate estimation of MLD using Artificial Neural Network methods and surface meteorology from a surface mooring in the Arabian Sea. The estimated MLD had a root mean square error of 7.36 m and a coefficient of determination (R2) of 0.94. About 67% (91%) of the estimates lie within ± 5 m (± 10 m) of the MLD determined from temperature sensors on the mooring.

Description: Author Posting. © American Geophysical Union, 2007. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 112 (2007): C06014, doi:10.1029/2006JC003947.

Description: In aerial surveys conducted during the Tropical Ocean–Global Atmosphere Coupled Ocean-Atmosphere Response Experiment and the low-wind component of the Coupled Boundary Layer Air-Sea Transfer (CBLAST-Low) oceanographic field programs, sea surface temperature (SST) variability at relatively short spatial scales (O(50 m) to O(1 km)) was observed to increase with decreasing wind speed. A unique set of coincident surface and subsurface oceanic temperature measurements from CBLAST-Low is used to investigate the subsurface expression of this spatially organized SST variability, and the SST variability is linked to internal waves. The data are used to test two previously hypothesized mechanisms for SST signatures of oceanic internal waves: a modulation of the cool-skin effect and a modulation of vertical mixing within the diurnal warm layer. Under conditions of weak winds and strong insolation (which favor formation of a diurnal warm layer), the data reveal a link between the spatially periodic SST fluctuations and subsurface temperature and velocity fluctuations associated with oceanic internal waves, suggesting that some mechanism involving the diurnal warm layer is responsible for the observed signal. Internal-wave signals in skin temperature very closely resemble temperature signals measured at a depth of about 20 cm, indicating that the observed internal-wave SST signal is not a result of modulation of the cool-skin effect. Numerical experiments using a one-dimensional upper ocean model support the notion that internal-wave heaving of the warm-layer base can produce alternating bands of relatively warm and cool SST through the combined effects of surface heating and modulation of wind-driven vertical shear.

Description: We gratefully acknowledge funding for this research from the Office of Naval Research through the CBLAST Departmental Research Initiative (grants N00014-01-1-0029, N00014-05-10090, N00014-01-1-0081, N00014-04-1-0110, N00014-05-1-0036, N00014-01-1-0080) and the Secretary of the Navy/Chief of Naval Operations Chair (grant N00014-99-1-0090).

Description: CLIMODE (CLIVAR Mode Water Dynamic Experiment) is a research program designed to understand and quantify the processes responsible for the formation and dissipation of North Atlantic subtropical mode water, also called Eighteen Degree Water (EDW). Among these processes, the amount of buoyancy loss at the ocean-atmosphere interface is still uncertain and needs to be accurately quantified. In November 2006, cruise 434 onboard R/V Oceanus traveled in the region of the separated Gulf Stream and its recirculation, where intense oceanic heat loss to the atmosphere in the winter is believed to trigger the formation of EDW. During this cruise, the surface mooring F that was anchored in the core of the Gulf Stream was replaced by a new one, as well as two subsurface moorings C and D located on the southeastern edge of the stream. Surface drifters, ARGO and bobbers RAFOS floats were deployed, CTD profiles and water samples were also carried out. This array of instruments will permit a characterization of EDW with high spatial and temporal resolutions and accurate in-situ measurements of air-sea fluxes in the EDW formation region. The present report documents this cruise, the methods and locations for the deployments of instruments and some evaluation of the measurements from these instruments.

Description: Funding was provided by the National Science Foundation under contract No. OCE04-24536

Description: The Ocean Reference Station at 20°S, 85°W under the stratus clouds west of northern Chile is being maintained to provide ongoing climate-quality records of surface meteorology; air-sea fluxes of heat, freshwater, and momentum; and of upper ocean temperature, salinity, and velocity variability. The Stratus Ocean Reference Station (ORS Stratus) is supported by the National Oceanic and Atmospheric Administration’s (NOAA) Climate Observation Program. It is recovered and redeployed annually, with cruises that have come between October and December. During the 2008 cruise on the NOAA ship Ronald H. Brown to the ORS Stratus site, the primary activities were recovery of the Stratus 8 WHOI surface mooring that had been deployed in October 2007, deployment of a new (Stratus 9) WHOI surface mooring at that site; in-situ calibration of the buoy meteorological sensors by comparison with instrumentation put on board by staff of the NOAA Earth System Research Laboratory (ESRL); and observations of the stratus clouds and lower atmosphere by NOAA ESRL. A buoy for the Pacific tsunami warning system was also serviced in collaboration with the Hydrographic and Oceanographic Service of the Chilean Navy (SHOA). The DART (Deep-Ocean Assessment and Reporting of Tsunami) carries IMET sensors and subsurface oceanographic instruments. A DART II buoy was deployed north of the STRATUS buoy, by personnel from the National Data Buoy Center (NDBC) Argo floats and drifters were launched, and CTD casts carried out during the cruise. The ORS Stratus buoys are equipped with two Improved Meteorological (IMET) systems, which provide surface wind speed and direction, air temperature, relative humidity, barometric pressure, incoming shortwave radiation, incoming longwave radiation, precipitation rate, and sea surface temperature. Additionally, the Stratus 8 buoy received a partial CO2 detector from the Pacific Marine Environmental Laboratory (PMEL). IMET data are made available in near real time using satellite telemetry. The mooring line carries instruments to measure ocean salinity, temperature, and currents. The ESRL instrumentation used during the 2008 cruise included cloud radar, radiosonde balloons, and sensors for mean and turbulent surface meteorology. Finally, the cruise hosted a teacher participating in NOAA’s Teacher at Sea Program.

Description: Funding was provided by the National Oceanic and Atmospheric Administration under Grant No. NA17RJ1223 for the Cooperative Institute for Climate and Ocean Research (CICOR).

Description: Author Posting. © American Geophysical Union, 2007. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 112 (2007): C03011, doi:10.1029/2007JC004135.

Description: Author Posting. © American Meteorological Society, 2009. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Bulletin of the American Meteorological Society 90 (2009): 1337-1350, doi:10.1175/2009BAMS2706.1.

Description: A major oceanographic field experiment is described, which is designed to observe, quantify, and understand the creation and dispersal of weakly stratified fluid known as “mode water” in the region of the Gulf Stream. Formed in the wintertime by convection driven by the most intense air–sea fluxes observed anywhere over the globe, the role of mode waters in the general circulation of the subtropical gyre and its biogeo-chemical cycles is also addressed. The experiment is known as the CLIVAR Mode Water Dynamic Experiment (CLIMODE). Here we review the scientific objectives of the experiment and present some preliminary results.

Description: Physical Oceanography program of NSF

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 Bulletin of the American Meteorological Society 88 (2007): 527-539, doi:10.1175/bams-88-4-527.

Description: A 25-yr (1981–2005) time series of daily latent and sensible heat fluxes over the global ice-free oceans has been produced by synthesizing surface meteorology obtained from satellite remote sensing and atmospheric model reanalyses outputs. The project, named Objectively Analyzed Air–Sea Fluxes (OAFlux), was developed from an initial study of the Atlantic Ocean that demonstrated that such data synthesis improves daily flux estimates over the basin scale. This paper introduces the 25-yr heat flux analysis and documents variability of the global ocean heat flux fields on seasonal, interannual, decadal, and longer time scales suggested by the new dataset. The study showed that, among all the climate signals investigated, the most striking is a long-term increase in latent heat flux that dominates the data record. The globally averaged latent heat flux increased by roughly 9 W m−2 between the low in 1981 and the peak in 2002, which amounted to about a 10% increase in the mean value over the 25-yr period. Positive linear trends appeared on a global scale, and were most significant over the tropical Indian and western Pacific warm pool and the boundary current regions. The increase in latent heat flux was in concert with the rise of sea surface temperature, suggesting a response of the atmosphere to oceanic forcing.

Description: The authors gratefully acknowledge support from NOAA through the Cooperative Institute for Climate and Oceanic Research (CICOR) at the Woods Hole Oceanographic Institution (WHOI). Supporting NOAA grants are from the Office of Climate Observations (OCO) and Climate Change Data and Detection (CCDD).