Recent Publications

Weekly Highlighted Publication

Multiple meltwater discharge and ice rafting events recorded in the deglacial sediments along the Beaufort Margin, Arctic Ocean

Impact:
Thick, acoustically transparent Holocene sediment imaged from Barrow Canyon to the Mackenzie Trough indicates that discharge down Barrow Canyon and sediment from the Alaskan continent were important sources during this time period, possibly due to rivers reworking glacial sediment exposed by the retreat of glacier ice on the Brooks Range. Acoustically laminated sediments with coarser grain size and higher magnetic susceptibility underlie the Holocene unit. The acoustic reflectivity and thickness of this unit increases towards the Mackenzie Trough, suggesting that it is the main source of the acoustically laminated sediment, in addition to ice-rafted debris (IRD) from the Amundsen and M'Clure ice streams.

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  • Kolody B.C, McCrow J.P, L. Allen Z, Aylward F.O, Fontanez K.M, Moustafa A., Moniruzzaman M., Chavez F.P, Scholin C.A, Allen EE et al..  2019.  Diel transcriptional response of a California Current plankton microbiome to light, low iron, and enduring viral infection.
    Abstract Summary:

    Phytoplankton and associated microbial communities provide organic carbon to oceanic food webs and drive ecosystem dynamics. However, capturing those dynamics is challenging. Here, an in situ, semi-Lagrangian, robotic sampler profiled pelagic microbes at 4 h intervals over ~2.6 days in North Pacific high-nutrient, low-chlorophyll waters. We report on the community structure and transcriptional dynamics of microbes in an operationally large...

  • Kranzler CF, Krause JW, Brzezinski MA, Edwards BR, Biggs WP, Maniscalco M, McCrow JP, Van Mooy BAS, Bidle KD, Allen AE et al..  2019.  Silicon limitation facilitates virus infection and mortality of marine diatoms.
    Abstract Summary:

    Diatoms are among the most globally distributed and ecologically successful organisms in the modern ocean, contributing upwards of 40% of total marine primary productivity1,2. By converting dissolved silicon into biogenic silica, and photosynthetically fixing carbon dioxide into particulate organic carbon, diatoms effectively couple the silicon (Si) and carbon cycles and ballast substantial vertical flux of carbon out of the euphotic zone...

  • Pearlman J., Bushnell M., Coppola L., Karstensen J, Buttigieg P.L, Pearlman F., Simpsons P., Barbier M., Muller-Karger F.E, Munoz-Mas C. et al..  2019.  Evolving and sustaining ocean best practices and standards for the next decade. 6
    Abstract Summary:

    The oceans play a key role in global issues such as climate change, food security, and human health. Given their vast dimensions and internal complexity, efficient monitoring and predicting of the planet's ocean must be a collaborative effort of both regional and global scale. A first and foremost requirement for such collaborative ocean observing is the need to follow well-defined and reproducible methods across activities: from strategies...

  • Lundesgaard O., Powell B., Merrifield M., Hahn-Woernle L., Winsor P..  2019.  Response of an Antarctic Peninsula fjord to summer katabatic wind events. 49:1485-1502.
    Abstract Summary:

    Fjords along the western Antarctic Peninsula are episodically exposed to strong winds flowing down marine-terminating glaciers and out over the ocean. These wind events could potentially be an important mechanism for the ventilation of fjord waters. A strong wind event was observed in Andvord Bay in December 2015, and was associated with significant increases in upper-ocean salinity. We examine the dynamical impacts of such wind events during...

  • Vittori G., Blondeaux P., Coco G., Guza RT.  2019.  Subharmonic edge wave excitation by narrow-band, random incident waves. 868
    Abstract Summary:

    A monochromatic, small amplitude, normally incident standing wave on a sloping beach is unstable to perturbation by subharmonic (half the frequency) edge waves. At equilibrium, edge wave shoreline amplitudes can exceed incident wave amplitudes. Here, the effect of incident wave randomness on subharmonic edge wave excitation is explored following a weakly nonlinear stability analysis under the assumption of narrow-band incident random waves....

  • Choy C.A, Robison B.H, Gagne T.O, Erwin B., Firl E., Halden R.U, Hamilton J.A, Katija K., Lisin S.E, Rolsky C. et al..  2019.  The vertical distribution and biological transport of marine microplastics across the epipelagic and mesopelagic water column. 9
    Abstract Summary:

    Plastic waste has been documented in nearly all types of marine environments and has been found in species spanning all levels of marine food webs. Within these marine environments, deep pelagic waters encompass the largest ecosystems on Earth. We lack a comprehensive understanding of the concentrations, cycling, and fate of plastic waste in sub-surface waters, constraining our ability to implement effective, large-scale policy and...

  • de Morals M.G, de Morais E.G, Duarte J.H, Deamici K.M, Mitchell B.G, Costa J.AV.  2019.  Biological CO2 mitigation by microalgae: technological trends, future prospects and challenges. 35
    Abstract Summary:

    The increase in the CO2 concentration in the Earth's atmosphere has been a topic of worldwide concern since anthropogenic emissions of greenhouse gases began increasing considerably during the industrial period. The effects of these mass emissions are probably the main cause of global warming, which has been observed over recent decades. Among the various techniques of CO2 capture, microalgal biofixation by photosynthesis is considered a...

  • Stukel M.R, Kelly T.B, Aluwihare LI, Barbeau K.A, Goericke R, Krause J.W, Landry MR, Ohman MD.  2019.  The Carbon:(234)Thorium ratios of sinking particles in the California current ecosystem 1: relationships with plankton ecosystem dynamics. Marine Chemistry. 212:1-15.
    Abstract Summary:

    We investigated variability in the C:Th-234 ratio of sinking particles and its relationship to changing water column characteristics and plankton ecological dynamics during 29 Lagrangian experiments conducted on six cruises of the California Current Ecosystem Long-Term Ecological Research (CCE-LTER) Program. C:Th-234 ratios of sinking particles collected by a surface-tethered sediment trap ((CThST)-Th-:234) varied from 2.3 to 20.5 mu mol C...

  • Broddrick J.T, Du N., Smith S.R, Tsuji Y., Jallet D., Ware M.A, Peers G., Matsuda Y., Dupont C.L, Mitchell B.G et al..  2019.  Cross-compartment metabolic coupling enables flexible photoprotective mechanisms in the diatom Phaeodactylum tricornutum. New Phytologist. 222:1364-1379.
    Abstract Summary:

    Photoacclimation consists of short- and long-term strategies used by photosynthetic organisms to adapt to dynamic light environments. Observable photophysiology changes resulting from these strategies have been used in coarse-grained models to predict light-dependent growth and photosynthetic rates. However, the contribution of the broader metabolic network, relevant to species-specific strategies and fitness, is not accounted for in these...

  • Hetherington E.D, Kurle C.M, Ohman MD, Popp BN.  2019.  Effects of chemical preservation on bulk and amino acid isotope ratios of zooplankton, fish, and squid tissues. 33:935-945.
    Abstract Summary:

    Rationale It is imperative to understand how chemical preservation alters tissue isotopic compositions before using historical samples in ecological studies. Specifically, although compound-specific isotope analysis of amino acids (CSIA-AA) is becoming a widely used tool, there is little information on how preservation techniques affect amino acid delta N-15 values. Methods We evaluated the effects of chemical preservatives on bulk tissue...

  • Eddebbar Y.A, Rodgers K.B, Long M.C, Subramanian AC, Xie SP, Keeling RF.  2019.  El Nino-like physical and biogeochemical ocean response to tropical eruptions. Journal of Climate. 32:2627-2649.
    Abstract Summary:

    The oceanic response to recent tropical eruptions is examined in Large Ensemble (LE) experiments from two fully coupled global climate models, the Community Earth System Model (CESM) and the Geophysical Fluid Dynamics Laboratory Earth System Model (ESM2M), each forced by a distinct volcanic forcing dataset. Following the simulated eruptions of Agung, El Chichon, and Pinatubo, the ocean loses heat and gains oxygen and carbon, in general...

  • Olli K., Halvorsen E., Vernet M, Lavrentyev P.J, Franze G., Sanz-Martin M., Paulsen M.L, Reigstad M..  2019.  Food web functions and interactions during spring and summer in the Arctic Water inflow region: Investigated through inverse modeling. 6
    Abstract Summary:

    We used inverse modeling to reconstruct major planktonic food web carbon flows in the Atlantic Water inflow, east and north of Svalbard during spring (18-25 May) and summer (9-13 August), 2014. The model was based on three intensively sampled stations during both periods, corresponding to early, peak, and decline phases of a Phaeocystis and diatom dominated bloom (May), and flagellates dominated post bloom stages (August). The food web carbon...

  • Young A.P, Carilli JE.  2019.  Global distribution of coastal cliffs. 44:1309-1316.
    Abstract Summary:

    Previous studies have estimated that coastal cliffs exist on about 80% of the global shoreline, but have not been validated on a global scale. This study uses two approaches to capture information on the worldwide existence and erosion of coastal cliffs: a detailed literature survey and imagery search, and a GIS-based global mapping analysis. The literature and imagery review show coastal cliffs exist in 93% of the combined recognized...

  • Levin L.A, Bett B.J, Gates A.R, Heimbach P., Howe B.M, Janssen F., McCurdy A., Ruhl H.A, Snelgrove P., Stocks K.I et al..  2019.  Global observing needs in the deep ocean. 6
    Abstract Summary:

    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...

  • White-Gaynor A.L, Nyblade A.A, Aster R.C, Wiens D.A, Bromirski PD, Gerstoft P, Stephen R.A, Hansen S.E, Wilson T., Dalziel I.W et al..  2019.  Heterogeneous upper mantle structure beneath the Ross Sea Embayment and Marie Byrd Land, West Antarctica, revealed by P-wave tomography. Earth and Planetary Science Letters. 513:40-50.
    Abstract Summary:

    We present an upper mantle P-wave velocity model for the Ross Sea Embayment (RSE) region of West Antarctica, constructed by inverting relative P-wave travel-times from 1881 teleseismic earthquakes recorded by two temporary broadband seismograph deployments on the Ross Ice Shelf, as well as by regional ice- and rock-sited seismic stations surrounding the RSE. Faster upper mantle P-wave velocities (similar to +1%) characterize the eastern part...

  • Anderson C.R, Berdalet E., Kudela R.M, Cusack C.K, Silke J., O'Rourke E., Dugan D., McCammon M., Newton J.A, Moore S.K et al..  2019.  Scaling up from regional case studies to a global Harmful Algal Bloom observing system. 6
    Abstract Summary:

    Harmful algal blooms (HABs) produce local impacts in nearly all freshwater and marine systems. They are a problem that occurs globally requiring an integrated and coordinated scientific understanding, leading to regional responses and solutions. Given that these natural phenomena will never be completely eliminated, an improved scientific understanding of HAB dynamics coupled with monitoring and ocean observations, facilitates new prediction...

  • Jagannathan A., Winters K., Armi L..  2019.  Stratified flows over and around long dynamically tall mountain ridges. 76:1265-1287.
    Abstract Summary:

    Uniformly stratified flows approaching long and dynamically tall ridges develop two distinct flow components over disparate time scales. The fluid upstream and below a "blocking level" is stagnant in the limit of an infinite ridge and flows around the sides when the ridge extent is finite. The streamwise half-width of the obstacle at the blocking level arises as a natural inner length scale for the flow, while the excursion time over this...

  • Lombard F., Boss E., Waite AM, Vogt M., Uitz J., Stemmann L., Sosik H.M, Schulz J., Romagnan J.B, Picheral M. et al..  2019.  Globally consistent quantitative observations of planktonic ecosystems. 6
    Abstract Summary:

    In this paper we review the technologies available to make globally quantitative observations of particles in general-and plankton in particular-in the world oceans, and for sizes varying from sub-microns to centimeters. Some of these technologies have been available for years while others have only recently emerged. Use of these technologies is critical to improve understanding of the processes that control abundances, distributions and...

  • Gutierrez-Rodriguez A., Stukel M.R, Santos A.L dos, Biard T., Scharek R., Vaulot D., Landry MR, Not F..  2019.  High contribution of Rhizaria (Radiolaria) to vertical export in the California Current Ecosystem revealed by DNA metabarcoding. Isme Journal. 13:964-976.
    Abstract Summary:

    Passive sinking of particulate organic matter (POM) is the main mechanism through which the biological pump transports surface primary production to the ocean interior. However, the contribution and variability of different biological sources to vertical export is not fully understood. Here, we use DNA metabarcoding of the 18S rRNA gene and particle interceptor traps (PITs) to characterize the taxonomic composition of particles sinking out of...

  • Spydell M.S, Feddersen F, Suanda S..  2019.  Inhomogeneous turbulent dispersion across the nearshore induced by surfzone eddies. Journal of Physical Oceanography. 49:1015-1034.
    Abstract Summary:

    In various oceanic regions, drifter-derived diffusivities reach a temporal maximum and subsequently decrease. Often, these are regions of inhomogeneous eddies, however, the effect of inhomogeneous turbulence on dispersion is poorly understood. The nearshore region (spanning from the surfzone to the inner shelf) also has strong cross-shore inhomogeneous turbulence. Nearshore Lagrangian statistics are estimated from drifter trajectories...

  • Thompson P.R, Widlansky M.J, Merrifield M.A, Becker J.M, Marra J.J.  2019.  A statistical model for frequency of coastal flooding in Honolulu, Hawaii, during the 21st century. 124:2787-2802.
    Abstract Summary:

    The state of Hawaii and city of Honolulu experienced an unprecedented number of minor flooding episodes during 2017 due to the combination of seasonal high tides and record-high mean sea levels. To quantify the impact of sea level rise on the tendency for flooding events to cluster in future years, we developed a hierarchical statistical model describing the number of days per year for which sea level exceeds a prescribed threshold in...

  • Negrete-Garcia G., Lovenduski N.S, Hauri C., Krumhardt K.M, Lauvset S.K.  2019.  Sudden emergence of a shallow aragonite saturation horizon in the Southern Ocean. Nature Climate Change. 9:313-+.
    Abstract Summary:

    Models project that with current CO2 emission rates, the Southern Ocean surface will be undersaturated with respect to aragonite by the end of this century(1-4). This will result in widespread impacts on biogeochemistry and ocean ecosystems(5-7), particularly the health of aragonitic organisms, such as pteropods(7), which can dominate polar surface water communities(6). Here, we quantify the depth of the present-day Southern Ocean aragonite...

  • Cape M.R, Vernet M, Pettit E.C, Wellner J., Truffer M., Akie G., Domack E., Leventer A., Smith C.R, Huber B.A.  2019.  Circumpolar deep water impacts glacial meltwater export and coastal biogeochemical cycling along the West Antarctic Peninsula. Frontiers in Marine Science. 6
    Abstract Summary:

    Warming along the Antarctic Peninsula has led to an increase in the export of glacial meltwater to the coastal ocean. While observations to date suggest that this freshwater export acts as an important forcing on the marine ecosystem, the processes linking ice-ocean interactions to lower trophic-level growth, particularly in coastal bays and fjords, are poorly understood. Here, we identify salient hydrographic features in Barilari Bay, a west...

  • Landry MR, Beckley L.E, Muhling B.A.  2019.  Climate sensitivities and uncertainties in food-web pathways supporting larval bluefin tuna in subtropical oligotrophic oceans. Ices Journal of Marine Science. 76:359-369.
    Abstract Summary:

    Compared with high-latitude seas, the ecological implications of climate change for top consumers in subtropical regions are poorly understood. One critical area of knowledge deficiency is the nature of food-web connections to larvae during their vulnerable time in the plankton. Bluefin tuna (BFT) are highly migratory temperate species whose early life stages are spent in ultra-oligotrophic subtropical waters. Dietary studies of BFT larvae...

  • Kim S, Hammerstrom K, Dayton P..  2019.  Epifaunal community response to iceberg-mediated environmental change in McMurdo Sound, Antarctica. Marine Ecology Progress Series. 613:1-14.
    Abstract Summary:

    High-latitude marine communities are dependent on sea ice patterns. Sea ice cover limits light, and hence primary production and food supply. Plankton, carried by currents from open water to areas under the sea ice, provides a transitory food resource that is spatially and temporally variable. We recorded epifaunal abundances at 17 sites in McMurdo Sound, Antarctica, over 12 yr, and found differences in communities based on location and time...

  • Stark J.S, Peltzer E.T, Kline DI, Queiros A.M, Cox T.E, Headley K., Barry J, Gazeau F., Runcie J.W, Widdicombe S. et al..  2019.  Free Ocean CO2 Enrichment (FOCE) experiments: Scientific and technical recommendations for future in situ ocean acidification projects. Progress in Oceanography. 172:89-107.
    Abstract Summary:

    Free Ocean CO2 Enrichment (FOCE) experiments are a relatively recent development in ocean acidification research, designed to address the need for in situ, long-term, community level experiments. FOCE studies have been conducted across different marine benthic habitats and regions, from Antarctica to the tropics. Based on this previous research we have formed some core operating principles that will aid those embarking on future FOCE...

  • de Verneil A., Franks PJS, Ohman MD.  2019.  Frontogenesis and the creation of fine-scale vertical phytoplankton structure. Journal of Geophysical Research-Oceans. 124:1509-1523.
    Abstract Summary:

    Fine-scale spatial structuring of phytoplankton patches has significant consequences for the marine food web, from altering phytoplankton exposure to surface light and limiting nutrients, to influencing the foraging of zooplankton, modifying carbon export, and impacting patterns of diversity. Hence, it is important to identify these fine-scale features and determine what generates their variability. Here we present evidence of fine-scale,...

  • Decima M, Stukel M.R, Lopez-Lopez L., Landry MR.  2019.  The unique ecological role of pyrosomes in the Eastern Tropical Pacific. Limnology and Oceanography. 64:728-743.
    Abstract Summary:

    Pyrosomes are an important but often overlooked component of marine zooplankton communities, with limited existing information regarding their ecological and trophic roles in pelagic ecosystems. We present the first estimates of grazing and trophic interactions of the large tropical pyrosome, Pyrostremma spinosum, in the Eastern Tropical Pacific. While patchy in distribution, Pyrostremma spinosum's grazing impact was substantial, up to 17.5%...

  • Dayton PK, Oliver JS, Thrush S.F, Hammerstrom K.  2019.  Bacteria defend carrion from scavengers. Antarctic Science. 31:13-15.
    Abstract Summary:

    Carrion in the form of dead seal pups and algal mats placed on soft bottom habitats at Explorers Cove and Salmon Bay, McMurdo Sound, attract scavenging invertebrates that are driven away by hydrogen sulphide produced by sulphate-reducing bacteria sequestered below a layer of Beggiatoa/Thioploca-like filamentous bacteria. This system is usually found for lipid-rich marine mammal carrion, but also occurred with natural algal mats.


  • Abstract Summary:

    The green microalga, Tetraselmis suecica, is commonly used in scientific, industrial, and aquacultural purposes because of its high stress tolerance and ease of culture in wide spectrums of environments. We hypothesized that carotenoids help to protect Tetraselmis cells from environmental stress by regulating genes in biosynthetic pathways. Here, we determined three major carotenogenic genes, phytoene synthase (PSY), phytoene desaturase (PDS...

  • Yarimizu K., Cruz-Lopez R., Garcia-Mendoza E., Edwards M., Carter ML, Carrano C.J.  2019.  Distribution of dissolved iron and bacteria producing the photoactive siderophore, vibrioferrin, in waters off Southern California and Northern Baja. 32:139-154.
    Abstract Summary:

    Phytoplankton blooms can cause acute effects on marine ecosystems due either to their production of endogenous toxins or to their enormous biomass leading to major impacts on local economies and public health. Despite years of effort, the causes of these Harmful Algal Blooms are still not fully understood. Our hypothesis is that bacteria that produce photoactive siderophores may provide a bioavailable source of iron for phytoplankton which...

  • Murik O., Tirichine L., Prihoda J., Thomas Y., Araujo W.L, Allen A.E, Fernie A.R, Bowler C..  2019.  Downregulation of mitochondrial alternative oxidase affects chloroplast function, redox status and stress response in a marine diatom. New Phytologist. 221:1303-1316.
    Abstract Summary:

    Diatom dominance in contemporary aquatic environments indicates that they have developed unique and effective mechanisms to cope with the rapid and considerable fluctuations that characterize these environments. In view of their evolutionary history from a secondary endosymbiosis, inter-organellar regulation of biochemical activities may be of particular relevance. Diatom mitochondrial alternative oxidase (AOX) is believed to play a...

  • Mullineaux L.S, Metaxas A., Beaulieu S.E, Bright M., Gollner S., Grupe B.M, Herrera S., Kellner J.B, Levin L.A, Mitarai S. et al..  2018.  Exploring the ecology of deep-sea hydrothermal vents in a metacommunity framework. Frontiers in Marine Science. 5
    Abstract Summary:

    Species inhabiting deep-sea hydrothermal vents are strongly influenced by the geological setting, as it provides the chemical-rich fluids supporting the food web, creates the patchwork of seafloor habitat, and generates catastrophic disturbances that can eradicate entire communities. The patches of vent habitat host a network of communities (a metacommunity) connected by dispersal of planktonic larvae. The dynamics of the metacommunity are...

  • Webb S.J, Rabsattt T., Erazo N., Bowman J.S.  2019.  Impacts of Zostera eelgrasses on microbial community structure in San Diego coastal waters. 7
    Abstract Summary:

    Marine eelgrasses are influential to their surrounding environments through their many ecosystem services, ranging from the provisioning of food and shelter for marine life to serving as a natural defense against pollution and pathogenic bacteria. In the marine waters of San Diego, CA, USA, eelgrass beds comprised of Zostera spp. are an integral part of the coastal ecosystem. To evaluate the impact of eelgrass on bacterial and archaeal...

  • Abstract Summary:

    Temperature and light are fundamental environmental variables which regulate phytoplankton growth rates when nutrients are in excess. For polar coastal oceans that are undergoing changes in sea ice cover and warming, light, and temperature are particularly important for bloom dynamics. Using colonial Phaeocystis antarctica cultures grown at steady-state, we assessed the combined effect of these two environmental controls on net growth rate (...

  • B. Pan J, Vernet M, Reynolds RA, B. Mitchell G.  2019.  The optical and biological properties of glacial meltwater in an Antarctic fjord. Plos One. 14
    Abstract Summary:

    As the Western Antarctic Peninsula (WAP) region responds to a warmer climate, the impacts of glacial meltwater on the Southern Ocean are expected to intensify. The Antarctic Peninsula fjord system offers an ideal system to understand meltwater’s properties, providing an extreme in the meltwater’s spatial gradient from the glacio-marine boundary to the WAP continental shelf. Glacial meltwater discharge in Arctic and Greenland fjords is...

  • Crosby S.C, Kumar N., O'Reilly W.C, Guza RT.  2019.  Regional swell transformation by backward ray tracing and SWAN. Journal of Atmospheric and Oceanic Technology. 36:217-229.
    Abstract Summary:

    Beach erosion and wave-induced flooding models are often initialized in O(10)-m depth, seaward of the surfzone, with wave conditions estimated from regional nonlinear spectral wave models [e.g., Simulating Waves Nearshore (SWAN)]. These models are computationally expensive for high-resolution, long-term regional O(100)-km hindcasts, and they limit examination of the effect of different climate scenarios on nearshore processes. Alternatively,...

  • Lee K.H, Jeong H.J, Lee K., Franks PJS, Seong K.A, Lee S.Y, Lee M.J, Jang S.H, Potvin E., Lim A.S et al..  2019.  Effects of warming and eutrophication on coastal phytoplankton production. Harmful Algae. 81:106-118.
    Abstract Summary:

    Phytoplankton production in coastal waters influences seafood production and human health and can lead to harmful algal blooms. Water temperature and eutrophication are critical factors affecting phytoplankton production, although the combined effects of warming and nutrient changes on phytoplankton production in coastal waters are not well understood. To address this, phytoplankton production changes in natural waters were investigated using...

  • Nickels C.F, Sala L.M, Ohman MD.  2019.  The euphausiid prey field for blue whales around a steep bathymetric feature in the southern California current system. Limnology and Oceanography. 64:390-405.
    Abstract Summary:

    Euphausiids are important prey for many marine organisms and often occur in patchy aggregations. Euphausiid predators, such as blue whales, may become concentrated in the vicinity of these aggregations. We investigated an area called Nine Mile Bank (NMB) near San Diego, California, defined by an area of steep bathymetry, to determine whether the frequent whale sightings in that locality can be explained by the distribution of euphausiids...

  • Till C.P, Solomon J.R, Cohen N.R, Lampe R.H, Marchetti A., Coale T.H, Bruland K.W.  2019.  The iron limitation mosaic in the California Current System: Factors governing Fe availability in the shelf/near-shelf region. Limnology and Oceanography. 64:109-123.
    Abstract Summary:

    The California Current System is a productive eastern boundary region off the coasts of Washington, Oregon, and California. There is strong seasonality to the region, with high levels of rainfall and river input to the coastal ocean during the winter season, and coastal and Ekman upwelling during the spring and summer. Iron (Fe) input to the coastal ocean during the winter months can be stored in the continental shelf mud belts and then be...

  • Swalethorp R., Dinasquet J., Logares R., Bertilsson S., Kjellerup S., Krabberod A.K, Moksnes P.O, Nielsen T.G, Riemann L..  2019.  Microzooplankton distribution in the Amundsen Sea Polynya (Antarctica) during an extensive Phaeocystis antarctica bloom. Progress in Oceanography. 170:1-10.
    Abstract Summary:

    In Antarctica, summer is a time of extreme environmental shifts resulting in large coastal phytoplankton blooms fueling the food web. Despite the importance of the microbial loop in remineralizing biomass from primary production, studies of how microzooplankton communities respond to such blooms in the Southern Ocean are rather scarce. Microzooplankton (ciliate and dinoflagellate) communities were investigated combining microscopy and 18S...

  • Hendrix A.R, Hurford T.A, Barge L.M, Bland M.T, Bowman J.S, Brinckerhoff W., Buratti B.J, Cable M.L, Castillo-Rogez J., Collins G.C et al..  2019.  The NASA Roadmap to Ocean Worlds. Astrobiology. 19:1-27.
    Abstract Summary:

    In this article, we summarize the work of the NASA Outer Planets Assessment Group (OPAG) Roadmaps to Ocean Worlds (ROW) group. The aim of this group is to assemble the scientific framework that will guide the exploration of ocean worlds, and to identify and prioritize science objectives for ocean worlds over the next several decades. The overarching goal of an Ocean Worlds exploration program as defined by ROW is to "identify ocean worlds,...

  • Fiedler J.W, Smit P.B, Brodie K.L, McNinch J., Guza RT.  2019.  The offshore boundary condition in surf zone modeling. Coastal Engineering. 143:12-20.
    Abstract Summary:

    Numerical models predicting surfzone waves and shoreline runup in field situations are often initialized with shoreward propagating (sea-swell, and infragravity) waves at an offshore boundary in 10-30 m water depth. We develop an offshore boundary condition, based on Fourier analysis of observations with co-located current and pressure sensors, that accounts for reflection and includes nonlinear phase-coupling. The performance of additional...

  • Taboada F.G, Barton A.D, Stock C.A, Dunne J., John J.G.  2019.  Seasonal to interannual predictability of oceanic net primary production inferred from satellite observations. Progress in Oceanography. 170:28-39.
    Abstract Summary:

    Seasonal to interannual predictions of ecosystem dynamics have the potential to improve the management of living marine resources. Prediction of oceanic net primary production (NPP), the foundation of marine food webs and the biological carbon pump, is particularly promising, with recent analysis suggesting that ecosystem feedback processes may lead to higher predictability of NPP at interannual scales than for physical variables like sea...

  • Highlighted Publication
    Dayton PK, Jarrell SC, Kim S, Parnell P.E, Thrush S.F, Hammerstrom K, Leichter J.J.  2019.  Benthic responses to an Antarctic regime shift: food particle size and recruitment biology. Ecological Applications. 29
    Abstract Summary:

    Polar ecosystems are bellwether indicators of climate change and offer insights into ecological resilience. In this study, we describe contrasting responses to an apparent regime shift of two very different benthic communities in McMurdo Sound, Antarctica. We compared species-specific patterns of benthic invertebrate abundance and size between the west (low productivity) and east (higher productivity) sides of McMurdo Sound across multiple...

  • Lampe R.H, Mann E.L, Cohen N.R, Till C.P, Thamatrakoln K., Brzezinski M.A, Bruland K.W, Twining B.S, Marchetti A..  2018.  Different iron storage strategies among bloom-forming diatoms. Proceedings of the National Academy of Sciences of the United States of America. 115:E12275-E12284.
    Abstract Summary:

    Diatoms are prominent eukaryotic phytoplankton despite being limited by the micronutrient iron in vast expanses of the ocean. As iron inputs are often sporadic, diatoms have evolved mechanisms such as the ability to store iron that enable them to bloom when iron is resupplied and then persist when low iron levels are reinstated. Two iron storage mechanisms have been previously described: the protein ferritin and vacuolar storage. To...

  • Neira C., Ingels J., Mendoza G., Hernandez-Lopez E., Levin L.A.  2018.  Distribution of meiofauna in bathyal sediments influenced by the oxygen minimum zone off Costa Rica. Frontiers in Marine Science. 5
    Abstract Summary:

    Ocean deoxygenation has become a topic of increasing concern because of its potential impacts on marine ecosystems, including oxygen minimum zone (OMZ) expansion and subsequent benthic effects. We investigated the influence of oxygen concentration and organic matter (OM) availability on metazoan meiofauna within and below an OMZ in bathyal sediments off Costa Rica, testing the hypothesis that oxygen and OM levels are reflected in meiofaunal...

  • Bowman J.S.  2018.  Identification of microbial dark matter in Antarctic environments. Frontiers in Microbiology. 9
    Abstract Summary:

    Numerous studies have applied molecular techniques to understand the diversity, evolution, and ecological function of Antarctic bacteria and archaea. One common technique is sequencing of the 16S rRNA gene, which produces a nearly quantitative profile of community membership. However, the utility of this and similar approaches is limited by what is known about the evolution, physiology, and ecology of surveyed taxa. When representative...

  • Dayton PK, Robilliard G.A, Oliver JS, Kim S, Hammerstrom K, O'Connor K, Fisher J., Barber J., Jarrell S..  2018.  Long-term persistence of wood on the sea floor at McMurdo Sound, Antarctica. Antarctic Science. 30:355-356.
    Abstract Summary:
  • Kuhn A.M, Fennel K., Berman-Frank I..  2018.  Modelling the biogeochemical effects of heterotrophic and autotrophic N-2 fixation in the Gulf of Aqaba (Israel), Red Sea. Biogeosciences. 15:7379-7401.
    Abstract Summary:

    Recent studies demonstrate that marine N-2 fixation can be carried out without light by heterotrophic N-2 fixers (diazotrophs). However, direct measurements of N-2 fixation in aphotic environments are relatively scarce. Heterotrophic as well as unicellular and colonial photoautotrophic diazotrophs are present in the oligotrophic Gulf of Aqaba (northern Red Sea). This study evaluates the relative importance of these different diazotrophs by...