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Monterey, CA, United States

Graham R.,Monterey Bay Aquarium Research Institute | Cortes J.,University of California at San Diego
IEEE Transactions on Automatic Control | Year: 2012

This work deals with trajectory optimization for a robotic sensor network sampling a spatio-temporal random field. We examine the optimal sampling problem of minimizing the maximum predictive variance of the estimator over the space of network trajectories. This is a high-dimensional, multi-modal, nonsmooth optimization problem, known to be NP-hard even for static fields and discrete design spaces. Under an asymptotic regime of near-independence between distinct sample locations, we show that the solutions to a novel generalized disk-covering problem are solutions to the optimal sampling problem. This result effectively transforms the search for the optimal trajectories into a geometric optimization problem. Constrained versions of the latter are also of interest as they can accommodate trajectories that satisfy a maximum velocity restriction on the robots. We characterize the solution for the unconstrained and constrained versions of the geometric optimization problem as generalized multicircumcenter trajectories, and provide algorithms which enable the network to find them in a distributed fashion. Several simulations illustrate our results. © 2011 IEEE. Source

Scholin C.A.,Monterey Bay Aquarium Research Institute
Ocean Science | Year: 2010

The OceanSensors08 workshop held 31 March- 4 April 2008 in Warnem̈unde, Germany, brought together an international group of marine scientists, sensor developers and technologists with a common interest in shaping the future of ocean sensing. In preparation for that meeting a series of review papers was commissioned, one of which was meant to cover Sensors for Ocean-omics. The "ocean-omics" topic was cast very broadly. The notion was to review use of genetic techniques for assessing presence and diversity of organisms, their genomic capacity and gene expression, and to provide a prospectus of how such methods could be applied in an autonomous capacity. I chose "ecogenomic sensor" as a descriptor to convey the essence of such a system - a device that integrates genetic level sensing with larger scale environmental characterization. This phrase is derived from workshops refining the US's Ocean Observatories Initiative (OOI) and visions for instrument systems that could be deployed on such a network. But what exactly are ecogenomic sensors? A clear definition is lacking and conceptualizations far outweigh actual hardware that can be deployed in the ocean. This prospectus builds from that point. I advance a definition of "ecogenomic sensor" and outline the opportunities and challenges associated with developing such instruments. Suggestions as to how this technology may be further refined and applied are offered against the backdrop of the Autonomous Microbial Genosensor (AMG) and Environmental Sample Processor (ESP). Applications that center on detection of DNA and RNA are emphasized. The word "review" appears in the title at the request of the editors. © 2010 Author(s). Source

Vrijenhoek R.C.,Monterey Bay Aquarium Research Institute
Molecular Ecology | Year: 2010

Deep-sea hydrothermal vents provide ephemeral habitats for animal communities that depend on chemosynthetic primary production. Sporadic volcanic and tectonic events destroy local vent fields and create new ones. Ongoing dispersal and cycles of extirpation and colonization affect the levels and distribution of genetic diversity in vent metapopulations. Several species exhibit evidence for stepping-stone dispersal along relatively linear, oceanic, ridge axes. Other species exhibit very high rates of gene flow, although natural barriers associated with variation in depth, deep-ocean currents, and lateral offsets of ridge axes often subdivide populations. Various degrees of impedance to dispersal across such boundaries are products of species-specific life histories and behaviours. Though unrelated to the size of a species range, levels of genetic diversity appear to correspond with the number of active vent localities that a species occupies within its range. Pioneer species that rapidly colonize nascent vents tend to be less subdivided and more diverse genetically than species that are slow to establish colonies at vents. Understanding the diversity and connectivity of vent metapopulations provides essential information for designing deep-sea preserves in regions that are under consideration for submarine mining of precious metals. © 2010 Blackwell Publishing Ltd. Source

Brewer P.G.,Monterey Bay Aquarium Research Institute
Biogeosciences | Year: 2013

This review covers the development of ocean acidification science, with an emphasis on the creation of ocean chemical knowledge, through the course of the 20th century. This begins with the creation of the pH scale by Sørensen in 1909 and ends with the widespread knowledge of the impact of the "High CO2 Ocean" by then well underway as the trajectory along the IPCC scenario pathways continues. By mid-century the massive role of the ocean in absorbing fossil fuel CO2 was known to specialists, but not appreciated by the greater scientific community. By the end of the century the trade-offs between the beneficial role of the ocean in absorbing some 90% of all heat created, and the accumulation of some 50% of all fossil fuel CO2 emitted, and the impacts on marine life were becoming more clear. This paper documents the evolution of knowledge throughout this period. © 2013 Author(s). Source

Haddock S.H.D.,Monterey Bay Aquarium Research Institute | Moline M.A.,California Polytechnic State University, San Luis Obispo | Case J.F.,University of California at Santa Barbara
Annual Review of Marine Science | Year: 2010

Bioluminescence spans all oceanic dimensions and has evolved many times from bacteria to fish to powerfully influence behavioral and ecosystem dynamics. New methods and technology have brought great advances in understanding of the molecular basis of bioluminescence, its physiological control, and its significance in marine communities. Novel tools derived from understanding the chemistry of natural light-producing molecules have led to countless valuable applications, culminating recently in a related Nobel Prize. Marine organisms utilize bioluminescence for vital functions ranging from defense to reproduction. To understand these interactions and the distributions of luminous organisms, new instruments and platforms allow observations on individual to oceanographic scales. This review explores recent advances, including the chemical and molecular, phylogenetic and functional, community and oceanographic aspects of bioluminescence. © 2010 by Annual Reviews. Source

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