@article {bhatt_overflow_2024,
	title = {Overflow waters in the western Irminger Sea modify deep sound speed structure and convergence zone propagation},
	journal = {The Journal of the Acoustical Society of America},
	volume = {155},
	number = {2},
	year = {2024},
	pages = {1216{\textendash}1229},
	abstract = {Deep sound speed structure in the western Irminger Sea is found to be highly dynamic in comparison to the adiabatic (uniform) sound speed gradient underpinning data assimilation and modeling efforts around the globe. A beamed source parabolic equation model is used to illustrate how the resulting non-uniform sound speed structure at 1 to 1.5 km in depth and sound speed inversion near the seafloor produce observable effects on acoustic signals between a shallow source and shallow vertical line array at convergence zone ranges. Beamforming analysis shows that a uniform sound speed gradient leads to {\textquotedblleft}ideal{\textquotedblright} interference patterns that do not capture or represent modeled convergence zone properties, such as location, strength, and sharpness. Overall findings suggest that in situ information about sound speed below 1 km is necessary for low frequency, long-range propagation studies, particularly in areas of complex thermohaline circulation.},
	keywords = {3706 Geophysics},
	issn = {0001-4966},
	doi = {10.1121/10.0024350},
	url = {https://doi.org/10.1121/10.0024350},
	author = {Bhatt, EeShan C. and Baggeroer, Arthur B. and Weller, Robert A.}
}
@article {RN148,
	title = {Constraining Southern Ocean Air-Sea-Ice Fluxes Through Enhanced Observations},
	journal = {Frontiers in Marine Science},
	volume = {6},
	year = {2019},
	pages = {421},
	type = {Journal Article},
	abstract = {Air-sea and air-sea-ice fluxes in the Southern Ocean play a critical role in global climate through their impact on the overturning circulation and oceanic heat and carbon uptake. The challenging conditions in the Southern Ocean have led to sparse spatial and temporal coverage of observations. This has led to a {\textquotedblleft}knowledge gap{\textquotedblright} that increases uncertainty in atmosphere and ocean dynamics and boundary-layer thermodynamic processes, impeding improvements in weather and climate models. Improvements will require both process-based research to understand the mechanisms governing air-sea exchange and a significant expansion of the observing system. This will improve flux parameterizations and reduce uncertainty associated with bulk formulae and satellite observations. Improved estimates spanning the full Southern Ocean will need to take advantage of ships, surface moorings, and the growing capabilities of autonomous platforms with robust and miniaturized sensors. A key challenge is to identify observing system sampling requirements. This requires models, Observing System Simulation Experiments (OSSEs), and assessments of the specific spatial-temporal accuracy and resolution required for priority science and assessment of observational uncertainties of the mean state and direct flux measurements. Year-round, high-quality, quasi-continuous in situ flux measurements and observations of extreme events are needed to validate, improve and characterize uncertainties in blended reanalysis products and satellite data as well as to improve parameterizations. Building a robust observing system will require community consensus on observational methodologies, observational priorities, and effective strategies for data management and discovery.},
	keywords = {air-sea/air-sea-ice fluxes, climate, ocean{\textendash}atmosphere interaction, ocean{\textendash}ice interaction, Southern Ocean},
	issn = {2296-7745},
	doi = {10.3389/fmars.2019.00421},
	url = {https://www.frontiersin.org/article/10.3389/fmars.2019.00421},
	author = {Swart, Sebastiaan and Gille, Sarah T. and Delille, Bruno and Josey, Simon and Mazloff, Matthew and Newman, Louise and Thompson, Andrew F. and Thomson, Jim and Ward, Brian and du Plessis, Marcel D. and Kent, Elizabeth C. and Girton, James and Gregor, Luke and Heil, Petra and Hyder, Patrick and Pezzi, Luciano Ponzi and de Souza, Ronald Buss and Tamsitt, Veronica and Weller, Robert A. and Zappa, Christopher J.}
}
@article {RN113,
	title = {Global Observing Needs in the Deep Ocean},
	journal = {Frontiers in Marine Science},
	volume = {6},
	year = {2019},
	pages = {241},
	type = {Journal Article},
	abstract = {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.

},
	keywords = {biodiversity, blue economy, deep sea, essential ocean variables, Ocean observation, ocean sensors},
	issn = {2296-7745},
	doi = {10.3389/fmars.2019.00241},
	url = {https://www.frontiersin.org/article/10.3389/fmars.2019.00241},
	author = {Levin, Lisa A. and Bett, Brian J. and Gates, Andrew R. and Heimbach, Patrick and Howe, Bruce M. and Janssen, Felix and McCurdy, Andrea and Ruhl, Henry A. and Snelgrove, Paul and Stocks, Karen I. and Bailey, David and Baumann-Pickering, Simone and Beaverson, Chris and Benfield, Mark C. and Booth, David J. and Carreiro-Silva, Marina and Cola{\c c}o, Ana and Ebl{\'e}, Marie C. and Fowler, Ashley M. and Gjerde, Kristina M. and Jones, Daniel O. B. and Katsumata, K. and Kelley, Deborah and Le Bris, Nadine and Leonardi, Alan P. and Lejzerowicz, Franck and Macreadie, Peter I. and McLean, Dianne and Meitz, Fred and Morato, Telmo and Netburn, Amanda and Pawlowski, Jan and Smith, Craig R. and Sun, Song and Uchida, Hiroshi and Vardaro, Michael F. and Venkatesan, R. and Weller, Robert A.}
}
@article {RN216,
	title = {Ocean Time Series Observations of Changing Marine Ecosystems: An Era of Integration, Synthesis, and Societal Applications},
	journal = {Frontiers in Marine Science},
	volume = {6},
	year = {2019},
	pages = {393},
	type = {Journal Article},
	abstract = {Sustained ocean time series are critical for characterizing marine ecosystem shifts in a time of accelerating, and at times unpredictable, changes. They represent the only means to distinguish between natural and anthropogenic forcings, and are the best tools to explore causal links and implications for human communities that depend on ocean resources. Since the inception of sustained ocean observations, ocean time series have withstood many challenges, most prominently availability of uninterrupted funding and retention of trained personnel. This OceanObs{\textquoteright}19 review article provides an overarching vision for sustained ocean time series observations for the next decade, focusing on the growing challenges of maintaining sustained ocean time series, including ship-based and autonomous coastal and open-ocean platforms, as well as remote sensing. In addition to increased diversification of funding sources to include the private sector, NGOs, and other groups, more effective engagement of stakeholders and other end-users will be critical to ensure the sustainability of ocean time series programs. Building a cohesive international time series network will require dedicated capacity to coordinate across observing programs and leverage existing infrastructure and platforms of opportunity. This review article outlines near-term observing priorities and technology needs; explores potential mechanisms to broaden ocean time series data applications and end-user communities; and describes current tools and future requirements for managing increasingly complex multi-platform data streams and developing synthesis products that support science and society. The actionable recommendations outlined herein ultimately form the basis for a robust, sustainable, fit-for-purpose time series network that will foster a predictive understanding of changing ocean systems for the benefit of society.},
	keywords = {climate, end-users, marine ecosystems, ocean time series, sustained observations, synthesis},
	issn = {2296-7745},
	doi = {10.3389/fmars.2019.00393},
	url = {https://www.frontiersin.org/article/10.3389/fmars.2019.00393},
	author = {Benway, Heather M. and Lorenzoni, Laura and White, Angelicque E. and Fiedler, Bj{\"o}rn and Levine, Naomi M. and Nicholson, David P. and DeGrandpre, Michael D. and Sosik, Heidi M. and Church, Matthew J. and O{\textquoteright}Brien, Todd D. and Leinen, Margaret and Weller, Robert A. and Karl, David M. and Henson, Stephanie A. and Letelier, Ricardo M.}
}
@article {RN24,
	title = {Overturning in the Subpolar North Atlantic Program: A New International Ocean Observing System},
	journal = {Bulletin of the American Meteorological Society},
	volume = {98},
	number = {4},
	year = {2017},
	pages = {737-752},
	type = {Journal Article},
	abstract = {For decades oceanographers have understood the Atlantic meridional overturning circulation (AMOC) to be primarily driven by changes in the production of deep-water formation in the subpolar and subarctic North Atlantic. Indeed, current Intergovernmental Panel on Climate Change (IPCC) projections of an AMOC slowdown in the twenty-first century based on climate models are attributed to the inhibition of deep convection in the North Atlantic. However, observational evidence for this linkage has been elusive: there has been no clear demonstration of AMOC variability in response to changes in deep-water formation. The motivation for understanding this linkage is compelling, since the overturning circulation has been shown to sequester heat and anthropogenic carbon in the deep ocean. Furthermore, AMOC variability is expected to impact this sequestration as well as have consequences for regional and global climates through its effect on the poleward transport of warm water. Motivated by the need for a mechanistic understanding of the AMOC, an international community has assembled an observing system, Overturning in the Subpolar North Atlantic Program (OSNAP), to provide a continuous record of the transbasin fluxes of heat, mass, and freshwater, and to link that record to convective activity and water mass transformation at high latitudes. OSNAP, in conjunction with the Rapid Climate Change{\textendash}Meridional Overturning Circulation and Heatflux Array (RAPID{\textendash}MOCHA) at 26{\textdegree}N and other observational elements, will provide a comprehensive measure of the three-dimensional AMOC and an understanding of what drives its variability. The OSNAP observing system was fully deployed in the summer of 2014, and the first OSNAP data products are expected in the fall of 2017.},
	issn = {0003-0007 1520-0477},
	doi = {10.1175/bams-d-16-0057.1},
	url = {https://staging-ddpp.dimensions.ai/details/publication/pub.1038223668 http://darchive.mblwhoilibrary.org/bitstream/1912/9015/1/bams-d-16-0057.1.pdf},
	author = {Susan Lozier, M. and Bacon, Sheldon and Bower, Amy S. and Cunningham, Stuart A. and Femke de Jong, M. and de Steur, Laura and deYoung, Brad and Fischer, J{\"u}rgen and Gary, Stefan F. and Greenan, Blair J. W. and Heimbach, Patrick and Holliday, Naomi P. and Houpert, Lo{\"\i}c and Inall, Mark E. and Johns, William E. and Johnson, Helen L. and Karstensen, Johannes and Li, Feili and Lin, Xiaopei and Mackay, Neill and Marshall, David P. and Mercier, Herl{\'e} and Myers, Paul G. and Pickart, Robert S. and Pillar, Helen R. and Straneo, Fiammetta and Thierry, Virginie and Weller, Robert A. and Williams, Richard G. and Wilson, Chris and Yang, Jiayan and Zhao, Jian and Zika, Jan D.}
}
