COLLABORATIVE RESEARCH: Centers for Ocean Science Education Excellence- Ocean in the Earth-Sun System

This award establishes a new Center for Ocean Science Education Excellence (COSEE) via awards to the Bigelow Laboratory for Ocean Sciences (0528706), the University of Maine (0528702), and the University of New Hampshire (0528686). The main goals of this thematic Center are to broaden understanding of the oceans in the context of the earth and solar systems and to help the COSEE network reach rural and inland audiences. The PIs will pioneer a system of interfaces, tools, and resources to reach underserved and underrepresented groups, and to bring ocean sciences to inland audiences by presenting it in the context of more familiar components of the earth system, including environmental and space sciences. One goal is to explore the effectiveness of expanding knowledge of the ocean\u27s role beyond being a driver of earth\u27s climate to placing the earth in the context of its unique place in the solar system. Activities include building and training educator-scientist teams to work towards specific goals, e.g., testing strategies for effective use of ocean data, training in the use of concept mapping, and the identification and evaluation of high-quality resources. Evaluation of products, models and information is integrated throughout, with continuous self-assessment. Formal education partners at the University of Maine and University of New Hampshire will test the efficacy of materials with educators whose knowledge of ocean-related content ranges from novice to expert. Maine will be a test bed for the COSEE network to start reaching inland rural populations. The team includes scientists and educators with expertise in the hydrosphere, biosphere, cryosphere, geosphere, and atmosphere. The team will develop concept maps and case studies that show application of ocean topics to the National Science Education Standards. The Center will develop a formal mechanism for scientific review of materials to ensure the products they recommend are of the highest quality and meet rigorous standards, as well as to provide feedback from educators and scientists to product developers. They will select resources from DLESE, the BRIDGE, NOAA and others and evaluate these for classroom readiness and scientific accuracy using their team of well-trained resource evaluators with first-hand knowledge of earth systems science. They also will do a gap analysis of missing resources. The Gap Analysis will also inform the science community about avoiding developing materials for well-covered topics. The review process developed by COSEE-OESS, from initial use of NASA\u27s education product review, will be disseminated nationally as a model for evaluating best practices and assessment and evaluation guidelines for education materials.In-service teacher programs will focus on expansion of University of New Hampshire\u27s Coastal Observing Center summer in-service teacher workshops to incorporate OESS content and evaluation of activities ( test bed for novel materials and activities). These workshops have annual themes focusing on ocean observing systems and the integration of buoy, shipboard, and satellite data (GoMOOS). Pre-service teachers and general science students at the University of Maine will take a new course created by OESS to learn ocean research methods by focusing on using physical principles, concepts and approaches to explain phenomena in aquatic sciences that are aligned to the NSES. The course will be developed for distribution to teachers after rigorous evaluation.Intellectual Merit of the Center: This thematic center focuses on creating and evaluating a series of interconnected tools and techniques designed to broaden understanding of the ocean in the context of the earth and solar systems. Results will be translated into innovative multimedia products that showcase the ocean in the earth-sun system. Educational resources will be evaluated for science and education impact, and gaps in these resources will be identified and filled. A new undergraduate course to teach about ocean phenomena will be developed, tested, and disseminated nationally. The proposed Center will help COSEE reach inland and rural audiences. Broader impact: This Center will serve as a learning organization to deliver excellent products, models, and information that can be applied virtually anywhere. The final products, publication of Best Practices (a document that describes the value of system context in terms of learning) and Strategies to reach inland audiences will be disseminated throughout and beyond the COSEE network

Hands-on Oceanography. Diffusion at Work: An Interactive Simulation

The goal of this activity is to help students better understand the nonintuitive concept of diffusion and introduce them to a variety of diffusion-related processes in the ocean. As part of this activity, students also practice data collection and statistical analysis (e.g., average, variance, and probability distribution functions). This activity is also used as an introduction for a subsequent lesson on stirring and mixing

Collaborative Proposal: Form and function of phytoplankton in unsteady, low Reynolds-number flows

Small-scale flow dynamics at low Reynolds numbers (Re) are important to phytoplankton cells in delivery of nutrients, sensory detection by and physical encounter with herbivores, accumulation of bacterial populations in the phycosphere or region immediately surrounding phytoplankton cells and coagulation of cells themselves as a mechanism terminating blooms. In nature most phytoplankton experience unsteady flows, i.e., velocities near the cells that vary with time due to the intermittency of turbulence and to discontinuous, spatially distributed pumping by herbivores. This unsteadiness has not previously been taken into account in models or measurements with plankton. Moreover, there have been decade- and century- long lags in moving relevant models of unsteady flow effects at low Re from applied mathematics and engineering to ecological applications. Engineering models show unsteady effects due to the history of formation of spatially extensive flow perturbations or wakes should be important to unsteady motions of moderately small biota. This project will address these affects. Non-swimming phytoplankton, and in particular diatoms, will be used as the simplest case where important unsteady flow behaviors should arise. This research activity will include a multi-level educational program, aimed at graduate research assistants, undergraduate research interns, undergraduate marine sciences majors and high-school teachers. Low-Re behaviors afford unusual opportunities to experience how mathematics, physics and biology inseparably catalyze understanding of phenomena that run counter to intuition. This activity will also include international collaborations with world experts on organism-flow interaction in Cambridge (T.J. Pedley) and Copenhagen (T. Kiorboe & A.W. Visser). The overall goals of the activity are to accelerate the flow of understanding from modelers to measurers to users of the information and back again. Educational materials that project U.S. national standards will be developed during intensive summer workshops with the high-school teachers and be made available on the web. Unsteady flow effects on phytoplankton will be predicted with explicit models based on singularity solutions (that involve the useful simplification that force is applied to the fluid at a small number of points) and mathematical models that include both the near field at low Re and the far field over a range of Re, both representative of nature. Singularity solutions allow explicit treatment of the role of complex cell shapes. Scaled-up analog models will be placed in a large Couette vessel to better visualize behaviors for both the research and teaching efforts. Natural-scale, but simplified, unsteady flows will be produced in smaller Couettes (nested, counter-rotating cylinders with seawater in the gap between the two cylinders) containing live phytoplankton and will be quantified by magnifying, particle-imaging velocimetry (PIV). Image analysis will be used to measure translation, rotation and flexural deformation of the phytoplankton. These studies will test various hypotheses derived from the general thesis that cell shapes and mechanical properties interact with unsteady flows to produce potentially fitness-enhancing, relative motions of the cell or chain and its surrounding fluids. A basic hypothesis is that unsteady fluid motion will interact with bending of cells to produce relative motion of fluid and phytoplankter. A very exciting prospect is that periodic instabilities known to arise at low Re may allow flexible organisms to act as self-organizing engines - through elasticity to harness energy from decaying turbulence and thereby move relative to the fluid. It is also expected that this study of passively bending structures in unsteady flows will help to understand the use of flexible appendages in swimming. The work is likely to aid significantly in associating functions with the shapes and spines of microplankton that are used in the identification of fossil specimens. By including relevant, unsteady fluid motions at low Re, the study will also provide firmer linkages between form and function in living plankton in the size range from 10 - 1000 mm that many large phytoplankton, invertebrate and fish larvae and other small zooplankton occupy

Hands-on Oceanography. Settling of Particles in Aquatic Environments Low Reynolds Numbers

The purpose of this activity is to familiarize students with how a particle’s size, shape and orientation affects its settling at low Reynolds numbers. This activity can also be used to teach statistical skills (e.g., replication of measurements, propagation of error, type I vs. type II regressions)

CMG Collaborative Research: Interactions of Phytoplankton with Dissipative Vortices

The aim of this project is to develop coordinated laboratory experiments and computational models to address a fundamental question in oceanography concerning magnitudes and mechanisms of turbulence effects on phytoplankton and other particles at the spatial scale of individual organisms. The importance of external energy in the form of turbulence in determining relative success of different kinds of phytoplankton dates to the seminal analysis of Munk and Riley (1952) and Margalef (1978). Margalef\u27s mandala asserts that high nutrient concentrations and turbulence intensities favor dominance by diatoms, whereas low values favor non-red-tide dinoflagellates. Subsequent work has revealed a wide spectrum of turbulence effects among species of dinoflagellates, including growth stimulation. The physicochemical mechanisms that govern these effects largely remain to be determined, however.Through iteration between innovative numerical models and experiments, the investigators will close a growing gap between textbook understanding of turbulent flows and understanding of consequences for suspended organisms and particles. Models and experiments have used one-dimensional shear to assess turbulence effects at the level of single cells and chains. Effects of fluid straining on concentration fields and cell rotation have been predicted, and effects on cell growth and motion, documented. Current understanding of turbulence, however, places greater emphasis on vorticity, gradients in vorticity and vortices at dissipation scales experienced by individual phytoplankton cells. We propose to develop a framework for both numerical and analog evaluation of effects that cells experience from being in and near viscous-scale vortices, that capture effects of vorticity as well as fluid deformation, evolution of concentration fields, and fluid-structure interactions. Roles of vorticity and gradients in vorticity in determining cell motions and thereby shaping concentration fields have been underappreciated, partly because a signature feature of turbulence, i.e., vortex stretching, is impossible in the two-dimensional flows that so far have been used as theoretical models and the primary basis of analog devices.Numerical approaches will use two simplified models of small-scale vortex structure and evolution, the Burgers vortex and the Lundgren stretched-spiral vortex, giving particular attention to diffusion of vorticity within and away from both. Both decaying and equilibrium vortices will be explored. Models of cells and chains of cells will be based on shapes and flexural stiffnesses of actual cells and chains. Each will be placed successively at a range of positions within and near a vortex and will be fully coupled mechanically to the fluid. Behaviors of interest are cell and chain translation, rotation and deformation and their feedbacks to local velocity and vorticity fields that could be used by grazers to locate a cell. Also to be modeled is the diffusion of scalars (nutrients with cell as sink or metabolites with cell as source), allowing calculation of diffusive fluxes for nutrient acquisition and prediction of chemical fields used by grazers. The investigators will further take advantage of their existing models of flow around flagella to include motile dinoflagellates in the modeling and measurement scheme.Analog experiments will exploit the fact that flows near Kolmogorov scale are dominated by viscosity, just as in earlier Couette experiments, but will incorporate realistic, 3D time variation. Borrowing from a burgeoning variety of geometries used in microfluidics, the investigators will construct a variety of small devices that utilize shed vortex streets, mild jets and cavity flows to match deformation rates, vorticities and gradients in them that produce interesting effects on phytoplankton in their numerical models of vortices. These analogs will be used to test the model predictions and to pose new questions of the models.Broader impacts: Results for phytoplankton extend easily to other important phenomena such as diffusion of attractants from eggs spawned in a turbulent environment (e.g., by abalone and other benthic invertebrates) and corresponding sperm swimming capabilities. They have implications for other important encounter processes such as particle coagulation and sedimentation, hydrosol filtration, and predator-prey interactions. This new approach provides both a natural bridge from larger-scale, direct numerical simulation (DNS) models of turbulence to these individual-scale effects of turbulence and a logical path to parameterizing these effects in larger-scale fluid dynamic models.Turbulence intensity is one of the parameters most likely to be influenced by climate change, and the investigators will work closely with the Center for Ocean Sciences Education Excellence Ocean Systems (COSEE-OS) that has chosen oceans under climate change as its major focus. They will also build on their history of providing teaching and outreach materials in biomechanics at low Reynolds numbers for graduate students, undergraduates and high-school teachers. They will complement both of these efforts with professionally produced, evocative visual animations of the important phenomena that they identify for incorporation into the COSEE-OS website

Teaching Physical Concepts in Oceanography: An Inquiry-Based Approach

This supplement to Oceanography magazine focuses on educational approaches to help engage students in learning and offers a collection of hands-on/minds-on activities for teaching physical concepts that are fundamental in oceanography. These key concepts include density, pressure, buoyancy, heat and temperature, and gravity waves. We focus on physical concepts for two reasons. First, students whose attraction to marine science stems from an interest in ocean organisms are typically unaware that physics is fundamental to understanding how the ocean, and all the organisms that inhabit it, function. Second, existing marine education and outreach programs tend to emphasize the biological aspects of marine sciences. While many K–12 activities focus on marine biology, comparatively few have been developed for teaching about the physical and chemical aspects of the marine environment (e.g., Ford and Smith, 2000, and a collection of activities on the Digital Library for Earth System Education Web site [DLESE; http://www.dlese.org/library/index.jsp]). The ocean provides an exciting context for science education in general and physics in particular. Using the ocean as a platform to which specific physical concepts can be related helps to provide the environmental relevance that science students are often seeking. The activities described in this supplement were developed as part of a Centers for Ocean Sciences Education Excellence (COSEE) collaboration between scientists and education specialists, and they were implemented in two undergraduate courses that targeted sophomores, juniors, and seniors (one for marine science majors and one including both science and education majors) and in four, week-long workshops for middle- and high-school science teachers. Support for this project was provided by the National Science Foundation\u27s Division of Ocean Sciences Centers for Ocean Sciences Education Excellence (COSEE), grant number OCE-0528702. Any opinions, findings, conclusions, or recommendations expressed in this publication do not necessarily reflect the views of NSF

Turbulence-plankton interactions : a new cartoon

Author Posting. © John Wiley & Sons, 2009. This is the author's version of the work. It is posted here by permission of John Wiley & Sons for personal use, not for redistribution. The definitive version was published in Marine Ecology 30 (2009): 133-150, doi:10.1111/j.1439-0485.2009.00288.x.Climate change will alter turbulence intensity, motivating greater attention to mechanisms of turbulence effects on organisms. Many analytic and analog models used to simulate and assess effects of turbulence on plankton rely on a one-dimensional simplification of the dissipative scales of turbulence, i.e., simple, steady, uniaxial shears, as produced in Couette vessels. There shear rates are constant and spatially uniform, and hence so is vorticity. Studies in such Couette flows have greatly informed, spotlighting stable orientations of nonspherical particles and predictable, periodic, rotational motions of steadily sheared particles in Jeffery orbits that steepen concentration gradients around nutrient-absorbing phytoplankton and other chemically (re)active particles. Over the last decade, however, turbulence research within fluid dynamics has focused on the structure of dissipative vortices in space and time and on spatially and temporally varying 2 vorticity fields in particular. Because steadily and spatially uniformly sheared flows are exceptional, so therefore are stable orientations for particles in turbulent flows. Vorticity gradients, finite net diffusion of vorticity and small radii of curvature of streamlines are ubiquitous features of turbulent vortices at dissipation scales that are explicitly excluded from simple, steady Couette flows. All of these flow components contribute instabilities that cause rotational motions of particles and so are important to simulate in future laboratory devices designed to assess effects of turbulence on nutrient uptake, particle coagulation and predatorprey encounter in the plankton. The Burgers vortex retains these signature features of turbulence and provides a simplified “cartoon” of vortex structure and dynamics that nevertheless obeys the Navier-Stokes equations. Moreover, this idealization closely resembles many dissipative vortices observed in both the laboratory and the field as well as in direct numerical simulations of turbulence. It is simple enough to allow both simulation in numerical models and fabrication of analog devices that selectively reproduce its features. Exercise of such numerical and analog models promises additional insights into mechanisms of turbulence effects on passive trajectories and local accumulations of both living and nonliving particles, into solute exchange with living and nonliving particles and into more subtle influences on sensory processes and swimming trajectories of plankton, including demersal organisms and settling larvae in turbulent bottom boundary layers. The literature on biological consequences of vortical turbulence has focused primarily on the smallest, Kolmogorov-scale vortices of length scale η. Theoretical dissipation spectra and direct numerical simulation, however, indicate that typical dissipative vortices with radii of 7η to 8η, peak azimuthal speeds of order 1 cm s-1 and lifetimes of order 10 s as a minimum (and much longer for moderate pelagic turbulence intensities) deserve new attention in studies of biological effects of turbulence.This research was supported by collaborative U.S. National Science Foundation grant (OCE- 0724744) to Jumars and Karp-Boss

Spectral backscattering properties of marine phytoplankton cultures

The backscattering properties of marine phytoplankton, which are assumed to vary widely with differences in size, shape, morphology and internal structure, have been directly measured in the laboratory on a very limited basis. This work presents results from laboratory analysis of the backscattering properties of thirteen phytoplankton species from five major taxa. Optical measurements include portions of the volume scattering function (VSF) and the absorption and attenuation coefficients at nine wavelengths. The VSF was used to obtain the backscattering coefficient for each species, and we focus on intra- and interspecific variability in spectral backscattering in this work. Ancillary measurements included chlorophyll-a concentration, cell concentration, and cell size, shape and morphology via microscopy for each culture. We found that the spectral backscattering properties of phytoplankton deviate from theory at wavelengths where pigment absorption is significant. We were unable to detect an effect of cell size on the spectral shape of backscattering, but we did find a relationship between cell size and both the backscattering ratio and backscattering crosssection. While particulate backscattering at 555 nm was well correlated to chlorophyll-a concentration for any given species, the relationship was highly variable between species. Results from this work indicate that phytoplankton cells may backscatter light at significantly higher efficiencies than what is predicted by Mie theory, which has important implications for closing the underwater and remotely sensed light budget

Distributions and Variability of Particulate Organic Matter in a Coastal Upwelling System

In this study we examined the spatial and temporal variability of particulate organic material (POM) off Oregon during the upwelling season. High-resolution vertical profiling of beam attenuation was conducted along two cross-shelf transects. One transect was located in a region where the shelf is relatively uniform and narrow (off Cascade Head (CH)); the second transect was located in a region where the shelf is shallow and wide (off Cape Perpetua (CP)). In addition, water samples were collected for direct analysis of chlorophyll, particulate organic carbon (POC), and particulate organic nitrogen (PON). Beam attenuation was highly correlated with POC and PON. Striking differences in distribution patterns and characteristics of POM were observed between CH and CP. Off CH, elevated concentrations of chlorophyll and POC were restricted to the inner shelf and were highly variable in time. The magnitude of the observed short-term temporal variability was of the same order as that of the seasonal variability reported in previous studies. Elevated concentrations of nondegraded chlorophyll and POM were observed near the bottom. Downwelling and rapid sinking are two mechanisms by which phytoplankton cells can be delivered to the bottom before being degraded. POM may be then transported across the shelf via the benthic nepheloid layer. Along the CP transect, concentrations of POM were generally higher than they were along the CH transect and extended farther across the shelf. Characteristics of surface POM, namely, C: N ratios and carbon: chlorophyll ratios, differed between the two sites. These differences can be attributed to differences in shelf circulation