Index Catalog // ScholarsArchive@OSU

Historical trends and future projections of climate and streamflow in the Willamette Valley and Rogue River Basins

Creator:: Dalton, Meghan, Rupp, David, Dello, Kathie, and Mote, Philip
Abstract:: A report to the US Army Corps of Engineers Portland District Office.
Resource Type:: Technical Report

The manganese and iron shuttle in a modern euxinic basin and implications for molybdenum cycling at euxinic ocean margins

Creator:: Scholz, Florian, McManus, James, and Sommer, Stefan
Abstract:: A meaningful application of Mo as a paleo-redox proxy requires an understanding of Mo cycling in modern reducing environments. Stagnant euxinic basins such as the Black Sea are generally regarded as model systems for understanding euxinic systems during early Earth history. However, drawing direct parallels between the Black Sea and...
Resource Type:: Article

Seasonality of U[superscript K’]₃₇ temperature estimates as inferred from sediment trap data

Creator:: Rosell-Melé, Antoni and Prahl, Fredrick G.
Abstract:: The seasonality of sea surface temperatures (SST) estimated from the alkenone-U[superscript K’]₃₇ index has been a debated issue since the development of the sediment trap time series data from 34 sampling locations, we show that the maximum alkenone flux in sediment traps varies markedly across the oceans, only on latitude...
Resource Type:: Article

Ecosystem effects of shell aggregations and cycling in coastal waters: an example of Chesapeake Bay oyster reefs

Creator:: Waldbusser, George G., Powell, Eric N., and Mann, Roger
Abstract:: Disease, overharvesting, and pollution have impaired the role of bivalves on coastal ecosystems, some to the point of functional extinction. An underappreciated function of many bivalves in these systems is shell formation. The ecological significance of bivalve shell has been recognized; geochemical effects are now more clearly being understood. A...
Resource Type:: Article

Particulate organic matter export by two contrasting small mountainous rivers from the Pacific Northwest, U.S.A.

Creator:: Goñi, Miguel A., Hatten, Jeff A., Wheatcroft, Robert A., and Borgeld, Jeffry C.
Abstract:: We investigated the export of particulate organic matter (POM) to the ocean by two contrasting small, mountainous rivers, the Umpqua and Eel Rivers, by collecting suspended sediment samples over a range of discharges and analyzing them for a variety of constituents, including organic carbon, nitrogen, biomarkers with distinct biochemical sources,...
Resource Type:: Article

Assessment of diffusive isotopic fractionation in polar firn, and application to ice core trace gas records

Creator:: Buizert, Christo, Sowers, Todd, and Blunier, Thomas
Abstract:: During rapid variations of the atmospheric mixing ratio of a trace gas, diffusive transport in the porous firn layer atop ice sheets and glaciers alters the isotopic composition of that gas relative to the overlying atmosphere. Records of past atmospheric trace gas isotopic composition from ice cores and firn need...
Resource Type:: Article

Non-additive and non-stationary properties in the spatial distribution of a large marine fish population

Creator:: Ciannelli, Lorenzo, Bartolino, Valerio, and Chan, Kung-Sik
Abstract:: Density-independent and density-dependent variables both affect the spatial distributions of species. However, their effects are often separately addressed using different analytical techniques. We apply a spatially explicit regression framework that incorporates localized, interactive and threshold effects of both density-independent (water temperature) and density-dependent (population abundance) variables, to study the spatial...
Resource Type:: Article

Satellite views of Pacific chlorophyll variability: comparisons to physical variability, local versus nonlocal influences and links to climate indices

Creator:: Thomas, Andrew C., Strub, P. Ted, Weatherbee, Ryan A., and James, Corinne
Abstract:: Concurrent satellite-measured chlorophyll (CHL), sea surface temperature (SST), sea level anomaly (SLA) and model-derived wind vectors from the 13+ year SeaWiFS period September 1997 – December 2010 quantify time and space patterns of phytoplankton variability and its links to physical forcing in the Pacific Ocean. The CHL fields are a...
Resource Type:: Preprint and Article

Periglacial debris-flow initiation and susceptibility and glacier recession from imagery, airborne LiDAR, and ground-based mapping

Creator:: Lancaster, Stephen T., Nolin, Anne W., Copeland, Elizabeth A., and Grant, Gordon E.
Abstract:: Climate changes in the Pacific Northwest, USA, may cause both retreat of alpine glaciers and increases in the frequency and magnitude of storms delivering rainfall at high elevations absent significant snowpack, and both of these changes may affect the frequency and severity of destructive debris flows initiating on the region's...
Resource Type:: Article

Satellite-based detection and monitoring of phytoplankton blooms along the Oregon coast

Creator:: McKibben, S. M., Strutton, P. G., Foley, D. G., Peterson, T. D., and White, A. E.
Abstract:: We have applied a normalized difference algorithm to 8 day composite chlorophyll-a (CHL) and fluorescence line height (FLH) imagery obtained from the Moderate Resolution Imaging Spectroradiometer aboard the Aqua spacecraft in order to detect and monitor phytoplankton blooms in the Oregon coastal region. The resulting bloom products, termed CHL[subscript rel]...
Resource Type:: Article

The Unpredictable Nature of Internal Tides on Continental Shelves

Creator:: Nash, Jonathan D., Kelly, Samuel M., Shroyer, Emily L., Moum, James N., and Duda, Timothy F.
Abstract:: Packets of nonlinear internal waves (NLIWs) in a small area of the Mid-Atlantic Bight were 10 times more energetic during a local neap tide than during the preceding spring tide. This counterintuitive result cannot be explained if the waves are generated near the shelf break by the local barotropic tide...
Resource Type:: Article

Ensemble-Based Data Assimilation for Estimation of River Depths

Creator:: Wilson, Greg and Özkan-Haller, H. Tuba
Abstract:: A method is presented for estimating bathymetry in a river, based on observations of depth-averaged velocity during steady flow. The estimator minimizes a cost function that combines known information in the form of a prior estimate and measured data (including measurement noise). State augmentation is used to relate the measured...
Resource Type:: Article

Baroclinic Frontal Instabilities and Turbulent Mixing in the Surface Boundary Layer. Part I: Unforced Simulations

Creator:: Skyllingstad, Eric D. and Samelson, R. M.
Abstract:: Interaction between mixed layer baroclinic eddies and small-scale turbulence is studied using a nonhydrostatic large-eddy simulation (LES) model. Free, unforced flow evolution is considered, for a standard initialization consisting of an 80-m-deep mixed layer with a superposed warm filament and two frontal interfaces in geostrophic balance, on a model domain...
Resource Type:: Article

Noble gases and coupled heat/fluid flow modeling for evaluating hydrogeologic conditions of volcanic island aquifers

Creator:: Heilweil, Victor M., Healy, Richard W., and Harris, Robert N.
Abstract:: Understanding groundwater conditions in the upland parts of volcanic island aquifers is critical for sustainable groundwater development in these resource-limited environments. Yet groundwater conditions in such settings are generally difficult to characterize because of sparse well drilling (high cost and/or limited access). Information needed for resource evaluation includes upland depth...
Resource Type:: Article

Dynamic range and sensitivity requirements of satellite ocean color sensors: learning from the past

Creator:: Hu, Chuanmin, Feng, Lian, Lee, Zhongping, Davis, Curtiss O., Mannino, Antonio, McClain, Charles R., and Franz, Bryan A.
Abstract:: Sensor design and mission planning for satellite ocean color measurements requires careful consideration of the signal dynamic range and sensitivity (specifically here signal-to-noise ratio or SNR) so that small changes of ocean properties (e.g., surface chlorophyll-a concentrations or Chl) can be quantified while most measurements are not saturated. Past and...
Resource Type:: Article

Ocean Mixing by Kelvin-Helmholtz Instability

Creator:: Smyth, William D. and Moum, James N.
Abstract:: Kelvin-Helmholtz (KH) instability, characterized by the distinctive finite-amplitude billows it generates, is an important mechanism in the development of turbulence in the stratified interior of the ocean. In particular, it is often assumed that the onset of turbulence in internal waves begins in this way. Clear recognition of the importance...
Resource Type:: Article

Effect of forecast skill on management of the Oregon coast coho salmon (Oncorhynchus kisutch) fishery

Creator:: Rupp, David E., Wainwright, Thomas C., and Lawson, Peter W.
Abstract:: Better fisheries management is often given as one justification for research on improving forecasts of fish survival. However, the value gained from expected improvements in forecast skill in terms of achieving management goals is rarely quantified as part of research objectives. Using Monte Carlo simulations of population dynamics, we assessed...
Resource Type:: Article

Rent Generation and Dissipation in the Western Central Pacific Ocean Tuna Fishery

Creator:: Harte, Michael
Abstract:: Proceedings of the Eighteenth Biennial Conference of the International Institute of Fisheries Economics and Trade, held July 11-15, 2016 at Aberdeen Exhibition and Conference Center (AECC), Aberdeen, Scotland, UK.
Resource Type:: Presentation and Conference Proceeding

Deeply dredged submarine HIMU glasses from the Tuvalu Islands, Polynesia: Implications for volatile budgets of recycled oceanic crust

Creator:: Jackson, M. G., Koga, K. T., Price, A., Koppers, A. A. P., Finlayson, V. A., Konrad, K., Hauri, E. H., Kylander-Clark, A., Kelley, K. A., and Kendrick, M. A.
Abstract:: Ocean island basalts (OIB) with extremely radiogenic Pb-isotopic signatures are melts of a mantle component called HIMU (high µ, high ²³⁸U/²⁰⁴Pb). Until now, deeply dredged submarine HIMU glasses have not been available, which has inhibited complete geochemical (in particular, volatile element) characterization of the HIMU mantle. We report major, trace...
Resource Type:: Article

Seasonal hydrologic responses to climate change in the Pacific Northwest

Creator:: Vano, Julie A., Nijssen, Bart, and Lettenmaier, Dennis P.
Abstract:: Increased temperatures and changes in precipitation will result in fundamental changes in the seasonal distribution of streamflow in the Pacific Northwest and will have serious implications for water resources management. To better understand local impacts of regional climate change, we conducted model experiments to determine hydrologic sensitivities of annual, seasonal,...
Resource Type:: Article

Legacy of Hydrate Ridge: an illustrated account

Creator:: Suess, Erwin
Abstract:: Hydrate Ridge has the distinction of hosting the first documented subduction-driven cold seep system that supports chemosynthetic life by Anaerobic Oxidation of Methane as well as the most widely researched methane hydrate setting at any active continental margin. Today this site is a vital node of Northeast Pacific regional long-term...
Resource Type:: Conference Proceeding

A field comparison of multiple techniques to quantify groundwater–surface-water interactions

Creator:: González-Pinzón, Ricardo, Ward, Adam S., Hatch, Christine E., Wlostowski, Adam N., Singha, Kamini, Gooseff, Michael N., Haggerty, Roy, Harvey, Judson W., Cirpka, Olaf A., and Brock, James T.
Abstract:: Groundwater–surface-water (GW-SW) interactions in streams are difficult to quantify because of heterogeneity in hydraulic and reactive processes across a range of spatial and temporal scales. The challenge of quantifying these interactions has led to the development of several techniques, from centimeter-scale probes to whole-system tracers, including chemical, thermal, and electrical...
Resource Type:: Article

Metabolic balance of coastal Antarctic waters revealed by autonomous pCO₂ and ΔO₂/Ar measurements

Creator:: Tortell, Philippe D., Asher, Elizabeth C., Ducklow, Hugh W., Goldman, Johanna A. L., Dacey, John W. H., Grzymski, Joseph J., Young, Jodi N., Kranz, Sven A., Bernard, Kim S., and Morel, François M. M.
Abstract:: We use autonomous gas measurements to examine the metabolic balance (photosynthesis minus respiration) of coastal Antarctic waters during the spring/summer growth season. Our observations capture the development of a massive phytoplankton bloom and reveal striking variability in pCO₂ and biological oxygen saturation (ΔO₂/Ar) resulting from large shifts in community metabolism...
Resource Type:: Article

Paired windward and leeward biogeochemical time series reveal consistent surface ocean CO₂ trends across the Hawaiian Ridge

Creator:: Dore, John E., Church, Matthew J., Karl, David M., Sadler, Daniel W., and Letelier, Ricardo M.
Abstract:: Sustained time series have provided compelling evidence for progressive acidification of the surface oceans through exchange with the growing atmospheric reservoir of carbon dioxide. However, few long-term programs exist, and extrapolation of results from one site to larger oceanic expanses is hampered by the lack of spatial coverage inherent to...
Resource Type:: Article

Air-Sea Interactions from Westerly Wind Bursts During the November 2011 MJO in the Indian Ocean

Creator:: Moum, James N., de Szoeke, Simon P., Smyth, William D., Edson, James B., DeWitt, H. Langley, Moulin, Aurélie J., Thompson, Elizabeth J., Zappa, Christopher J., Rutledge, Steven A., Johnson, Richard H., and Fairall, Christopher W.
Abstract:: The life cycles of three Madden–Julian oscillation (MJO) events were observed over the Indian Ocean as part of the Dynamics of the MJO (DYNAMO) experiment. During November 2011 near 0°, 80°E, the site of the research vessel Roger Revelle, the authors observed intense multiscale interactions within an MJO convective envelope,...
Resource Type:: Article

Earliest Holocene south Greenland ice sheet retreat within its late Holocene extent

Creator:: Carlson, Anders E., Winsor, Kelsey, Ullman, David J., Brook, Edward J., Hood, Dylan H., Axford, Yarrow, LeGrande, Allegra N., Anslow, Faron S., and Sinclair, Gaylen
Abstract:: Early Holocene summer warmth drove dramatic Greenland ice sheet (GIS) retreat. Subsequent insolation-driven cooling caused GIS margin readvance to late Holocene maxima, from which ice margins are now retreating. We use ¹⁰Be surface exposure ages from four locations between 69.4°N and 61.2°N to date when in the early Holocene south...
Resource Type:: Article

Limacina helicina shell dissolution as an indicator of declining habitat suitability owing to ocean acidification in the California Current Ecosystem

Creator:: Bednaršek, N., Feely, R. A., Reum, J. C. P., Peterson, B., Menkel, J., Alin, S. R., and Hales, B.
Abstract:: Few studies to date have demonstrated widespread biological impacts of ocean acidification (OA) under conditions currently found in the natural environment. From a combined survey of physical and chemical water properties and biological sampling along the Washington–Oregon–California coast in August 2011, we show that large portions of the shelf waters...
Resource Type:: Article

Biological production in the NE Pacific and its influence on air-sea CO2 flux: Evidence from dissolved oxygen isotopes and O2/Ar

Creator:: Juranek, L. W., Quay, P. D., Feely, R. A., Lockwood, D., Karl, D. M., and Church, M. J.
Abstract:: We determine rates of gross photosynthetic O₂ production (GOP) and net community O₂ production (NCP) using the triple oxygen isotope and O₂/Ar approach on two spring and two late summer meridional transects of the NE Pacific. Observed GOP and NCP in the subtropical (89 ± 9 and 8.3 ± 1.3...
Resource Type:: Article

Global climate evolution during the last deglaciation

Creator:: Clark, Peter U., Shakun, Jeremy D., Baker, Paul A., Bartlein, Patrick J., Brewer, Simon, Brook, Edward J., Carlson, Anders E., Cheng, Hai, Kaufman, Darrell S., Liu, Zhengyu, Marchitto, Thomas M., Mix, Alan C., Morrill, Carrie, Otto-Bliesner, Bette L., Pahnke, Katharina, Russell, James M., Whitlock, Cathy, Adkins, Jess F., Blois, Jessica L., Clark, Jorie, Colman, Steven M., Curry, William B., Flower, Ben P., He, Feng, Johnson, Thomas C., Lynch-Stieglitz, Jean, Markgraf, Vera, McManus, Jerry, Mitrovica, Jerry X., Moreno, Patricio I., and Williams, John W.
Abstract:: Deciphering the evolution of global climate from the end of the Last Glacial Maximum approximately 19 ka to the early Holocene 11 ka presents an outstanding opportunity for understanding the transient response of Earth's climate system to external and internal forcings. During this interval of global warming, the decay of...
Resource Type:: Article

Geographically and environmentally driven spawning distributions of tuna species in the western Mediterranean Sea

Creator:: Reglero, Patricia, Ciannelli, Lorenzo, Alvarez-Berastegui, D., Balbin, R., Lopez-Jurado, J. L., and Alemany, F.
Abstract:: The spawning habitats of many large marine pelagic predators are poorly known. This lack of knowledge hampers conservation efforts that are aimed at identifying critical habitats for the spawning of these species. We hypothesized that phylogenetically related species show different adaptations and respond differently to environmental and geographical cues for...
Resource Type:: Article

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