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The authors discuss water column measurements obtained using a light absorption and attenuation instrument mounted on a SeaSoar, a towed undulating vehicle.

The purpose of Oregon’s Nearshore Research Inventory (NRI) project was to understand the geographic use of ocean space by the marine science community in order to include the information in Oregon’s marine spatial planning (MSP) process. Spatial data and attributes about the geographic use of Oregon’s ocean and coast by marine scientists were inventoried and mapped; including information about the geographic distribution of research, research timelines, and the people and institutions that conduct scientific research. The results of the NRI interviews show that the scientific community conducts research in twenty percent of the nearshore grid cells used in the Oregon’s Territorial Sea amendment process. These results show that ocean space is used by the scientific community, and therefore, should be recognized as a use of ocean space in the MSP process. As new uses, such as wave energy extraction, are proposed along coastlines and in the ocean, MSP can be used as a tool to reduce conflict and find compatible uses of ocean and coastal space. A major benefit of the scientific community’s use of ocean and coastal space is that it results in data that can be used to inform ecosystem-based management decisions. Interruptions in long-term scientific research and monitoring as a result of ocean space use conflicts could limit the availability of information for use in future management decisions. While considering tradeoffs in the MSP process, decision makers need to recognize and account for the value of scientific space as a use of the ocean. [ABSTRACT FROM AUTHOR]

Abstract: A central challenge for natural resource management is developing rigorous yet practical approaches for balancing the costs and benefits of diverse human uses of ecosystems. Economic theory has a long history of evaluating tradeoffs in returns from different assets to identify optimal investment strategies. There has been recent progress applying this framework to the delivery of ecosystem services in land use planning. However, despite growing national and international interest in marine spatial planning, there is a lack of parallel frameworks in the marine realm. This paper reviews an ecosystem service tradeoff analysis framework and provides a more comprehensive synthesis for how it can be applied to marine spatial planning and marine ecosystem-based management. A tradeoff analysis approach can reveal inferior management options, demonstrate the benefits of comprehensive planning for multiple, interacting services over managing single services, and identify ‘compatible’ services that provide win–win management options. [Copyright &y& Elsevier]

Abstract: The California Current System (CCS) is forced by the distribution of atmospheric pressure and associated winds in relation to the west coast of North America. In this paper, we begin with a simplified case of winds and a linear coast, then consider variability characteristic of the CCS, and conclude by considering future change. The CCS extends from the North Pacific Current (∼50°N) to off Baja California, Mexico (∼15–25°N) with a major discontinuity at Point Conception (34.5°N). Variation in atmospheric pressure affects winds and thus upwelling. Coastal, wind-driven upwelling results in nutrification and biological production and a southward coastal jet. Offshore, curl-driven upwelling results in a spatially large, productive habitat. The California Current flows equatorward and derives from the North Pacific Current and the coastal jet. Dominant modes of spatial and temporal variability in physical processes and biological responses are discussed. High surface production results in deep and bottom waters depleted in oxygen and enriched in carbon dioxide. Fishing has depleted demersal stocks more than pelagic stocks, and marine mammals, including whales, are recovering. Krill, squid, and micronekton are poorly known and merit study. Future climate change will differ from past change and thus prediction of the CCS requires an understanding of its dynamics. Of particular concern are changes in winds, stratification, and ocean chemistry. [Copyright &y& Elsevier]

Abstract: During spring and summer 2000, two mesoscale mapping cruises were carried out in the northern California Current System between and and between the shallow, inner continental shelf and up to 150km offshore. Measurements were made using a towed undulating vehicle equipped with a conductivity-temperature-depth instrument and a chlorophyll fluorometer. A shipboard acoustic Doppler current profiler (ADCP) measured water velocities, and surface drifter trajectories and satellite sea-surface temperature imagery provide context for the mesoscale maps. Nearly identical upwelling favorable wind stresses of up to existed during both the spring and summer surveys. Early in the season (late May, early June) the upwelling front and jet followed the continental shelf bottom topography. There was cold water inshore of the shelfbreak all along the coast with pockets of elevated phytoplankton biomass (chlorophyll (chl) up to ) near the coast. Mesoscale activity was minimal. During late-summer (August), the upwelling front and jet were much more convoluted, including significant meanders offshore associated with a major submarine bank (Heceta Bank, 44.0–) and a large coastal promontory (Cape Blanco, ). High levels of phytoplankton biomass were found over Heceta Bank (chl ) and near the coast south of Cape Blanco (chl ). Low velocities inshore of Heceta Bank, measured by both shipboard ADCP and surface drifters, indicate the potential for retention of water over the Bank, leading to favorable conditions for phytoplankton biomass accumulation. The large offshore meander near Cape Blanco carried cold, nutrient-rich, high phytoplankton biomass (chl of 2–) water over 100km offshore. This flow–topography interaction feature was generated in mid-June and remained an important part of the regional circulation for about 2.5 months. [Copyright &y& Elsevier]

Provides information on a study which examined the coastal upwelling region near Cape Blanco, Oregon, using a conductivity-temperature-depth on SeaSoar, an acoustic Doppler current profiler, surface temperature maps and surface drifters. Data analysis and methods; Results and discussion.

• Mesoscale eddies impact the marine ecosystem of the North Pacific and its marginal Seas. • Impacts vary with time and regions. Knowns and unknowns are summarized. • How climate change will modify mesoscale processes remains a key open challenge. Physical transport dynamics occurring at the ocean mesoscale (∼20 km – 200 km) largely determine the environment in which biogeochemical processes occur. As a result, understanding and modeling mesoscale transport is crucial for determining the physical modulations of the marine ecosystem. This review synthesizes current knowledge of mesoscale eddies and their impacts on the marine ecosystem across most of the North Pacific and its marginal Seas. The North Pacific domain north of 20°N is divided in four regions, and for each region known, unknowns and known-unknowns are summarized with a focus on physical properties, physical-biogeochemical interactions, and the impacts of climate variability and change on the eddy field and on the marine ecosystem. [ABSTRACT FROM AUTHOR]

Abstract: Associations between cetacean distributions, oceanographic features, and bioacoustic backscatter were examined during two process cruises in the northern California Current System (CCS) during late spring and summer 2000. Line-transect surveys of cetaceans were conducted across the shelf and slope, out to 150km offshore from Newport, Oregon (44.6°N) to Crescent City, California (41.9°N), in conjunction with multidisciplinary mesoscale and fine-scale surveys of ocean and ecosystem structure. Occurrence patterns (presence/absence) of cetaceans were compared with hydrographic and ecological variables (e.g., sea surface salinity, sea surface temperature, thermocline depth, halocline depth, chlorophyll maximum, distance to the center of the equatorward jet, distance to the shoreward edge of the upwelling front, and acoustic backscatter at 38, 120, 200 and 420kHz) derived from a towed, undulating array and a bioacoustic system. Using a multiple logistic regression model, 60.2% and 94.4% of the variation in occurrence patterns of humpback whales Megaptera novaeangliae during late spring and summer, respectively, were explained. Sea surface temperature, depth, and distance to the alongshore upwelling front were the most important environmental variables during June, when humpbacks occurred over the slope (200–2000m). During August, when humpbacks concentrated over a submarine bank (Heceta Bank) and off Cape Blanco, sea surface salinity was the most important variable, followed by latitude and depth. Humpbacks did not occur in the lowest salinity water of the Columbia River plume. For harbor porpoise Phocoena phocoena, the model explained 79.2% and 70.1% of the variation in their occurrence patterns during June and August, respectively. During spring, latitude, sea surface salinity, and thermocline gradient were the most important predictors. During summer, latitude and distance to the inshore edge of the upwelling front were the most important variables. Typically a coastal species, harbor porpoises extended their distribution farther offshore at Heceta Bank and at Cape Blanco, where they were associated with the higher chlorophyll concentrations in these regions. Pacific white-sided dolphin Lagenorhynchus obliquidens was the most numerous small cetacean in early June, but was rare during August. The model explained 44.5% of the variation in their occurrence pattern, which was best described by distance to the upwelling front and acoustic backscatter at 38kHz. The model of the occurrence pattern of Dall''s porpoise Phocoenoides dalli was more successful when mesoscale variability in the CCS was higher during summer. Thus, the responses of cetaceans to biophysical features and upwelling processes in the northern CCS were both seasonally and spatially specific. Heceta Bank and associated flow-topography interactions were very important to a cascade of trophic dynamics that ultimately influenced the distribution of foraging cetaceans. The higher productivity associated with upwelling near Cape Blanco also had a strong influence on the distribution of cetaceans. [Copyright &y& Elsevier]

• A multi-stage milling used less energy by 43 % than did a single-stage. • Multi-stage milling runs more stable in grinding high-moisture content materials. • Bond's comminution law relates better starting size, product size, and energy. • The equations estimates the energy consumption to a target particle size. This study has evaluated the comminution energy reduction efficiency of a multi-stage milling method and established a mathematical model for estimating the specific energy consumption as a function of moisture content and particle size change. A Bliss hammer mill was employed to grind the feedstock targeting at two final screen sizes of 0.84 and 0.69 mm. For the target screen size of 0.84 mm, the single-stage, two-stage, and three-stage milling process were employed. Whereas, the single-stage, two-stage, and four-stage milling process were employed for the 0.69-mm target screen size. Four moisture content levels were employed, i.e. 6 %, 12 %, 18 %, and 28 %. While the final particle sizes and distributions were similar independent of the intermediate stages, the results showed that the single-stage milling consumed 43 % more energy than the three-stage grinding process. Also, multi-stage milling runs more stable in grinding high-moisture content materials. In addition, a mathematical model based on Bond's comminution law was established to predict the specific energy consumption with the moisture content and the particle sizes before and after grinding. [ABSTRACT FROM AUTHOR]

Abstract: Declining ocean health, increasing human demands on marine ecosystems, and a history of management focused on individual activities, species or sectors has led to calls for more comprehensive, integrated management that considers entire coupled social-ecological systems. This transition to ecosystem-based management (EBM) for the oceans will certainly face a number of hurdles, and many practitioners struggle with how to move forward with EBM. In this paper, we assess whether the necessary science exists to support EBM. Specifically, we evaluate the state of the social and natural sciences for three research areas that are critical to EBM: (1) ecosystem services, (2) cumulative impacts, and (3) ecosystem variability and change. For each of the three research areas, we describe its importance to EBM and assess existing and emerging information and application of this knowledge, focusing on the US West Coast. We conclude that available science is not the bottleneck for moving forward with comprehensive EBM for this region, although we highlight important remaining knowledge gaps, particularly within the social sciences. Given imperfect and uncertain knowledge, EBM calls for an adaptive management approach, starting with readily available information, and continuously adapting as new information emerges. This synthesis can serve as a basis for comparison for other regions; it provides guidance for organizing information in support of EBM and outlines many novel and broadly applicable scientific approaches. [Copyright &y& Elsevier]

Abstract: Spatial and temporal variability in regimes of coastal upwelling may have profound effects on the distribution and local dynamics of coastal marine populations and entire communities. Currently available mesoscale indices for upwelling intensity lack the resolution needed to characterize and compare inner-shelf upwelling regimes at small spatial scales (1–10’s km), which is often required to test relevant hypotheses in ecology, conservation, and management. We present local, quantitative indices of thermal variability, whose pattern across sites is largely driven by variation in coastal upwelling intensity at scales of few kilometers. Index calculations were based on daily records of in situ Sea Surface Temperature [SST], gathered at 30 sites along the Oregon–California coast, and at 25 sites along the coast of northern and central Chile. Several univariate metrics were calculated using daily series of temperature anomalies, and combined to produce a multivariate ordination of sites (Multivariate Upwelling Zone Index of Cooling, MUZIC) that allowed us to compare sites across regions. Multivariate indices calculated for 13 central Chile sites explained 52% and 50% of the among-site variance in corticated algal biomass and growth rate, respectively. Upwelling-induced variability at the scales documented here can have significant consequences on the ecology of coastal ecosystems. The basic data requirements (i.e. SST time series) and the simplicity of calculation make these indices a useful tool to apply at a large number of sites around the world, and to examine the generality of community- and population-level responses to physical forcing. [Copyright &y& Elsevier]

Abstract: As a part of the GLOBEC-Northeast Pacific project, we investigated variation in the abundance of marine birds in the context of biological and physical habitat conditions in the northern portion of the California Current System (CCS) during cruises during the upwelling season 2000. Continuous surveys of seabirds were conducted simultaneously in June (onset of upwelling) and August (mature phase of upwelling) with ocean properties quantified using a towed, undulating vehicle and a multi-frequency bioacoustic instrument (38–420kHz). Twelve species of seabirds contributed 99% of the total community density and biomass. Species composition and densities were similar to those recorded elsewhere in the CCS during earlier studies of the upwelling season. At a scale of 2–4km, physical and biological oceanographic variables explained an average of 25% of the variation in the distributions and abundance of the 12 species. The most important explanatory variables (among 14 initially included in each multiple regression model) were distance to upwelling-derived frontal features (center and edge of coastal jet, and an abrupt, inshore temperature gradient), sea-surface salinity, acoustic backscatter representing various sizes of prey (smaller seabird species were associated with smaller prey and the reverse for larger seabird species), and chlorophyll concentration. We discuss the importance of these variables in the context of what factors seabirds may use to find food. The high seabird density in the Heceta Bank and Cape Blanco areas indicates them to be refuges contrasting the low seabird densities currently found in most other parts of the CCS, following decline during the recent warm regime of the Pacific Decadal Oscillation. [Copyright &y& Elsevier]

Abstract: The location and size of euphausiid aggregations (patches) were identified using acoustic volume backscattering strength at 38 and 120kHz and vertically stratified MOCNESS sampling during a US GLOBEC cruise off southern Oregon and northern California in August 2000. Euphausiid patches were clustered inshore of Heceta Bank (44.0°N) and off Cape Blanco (42.8°N), but were not common elsewhere. The distribution of euphausiid patches throughout the study area was correlated with that of near-surface chlorophyll. We suggest that Heceta Bank and Cape Blanco were zones of plankton retention and concentration along the shelf and slope, and also that large offshore meanders in the equatorward upwelling jet carried upwelled water, chlorophyll, and euphausiids offshore. In particular, the complex interaction of mesoscale physical features, shoaling bottom topography, and diel vertical migration created large patches of euphausiids. These euphausiid patches, probably persisting on timescales of days to weeks, could function as relatively large and persistent resources for euphausiid predators. [Copyright &y& Elsevier]