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Greatly enhanced atmospheric carbon dioxide (CO2) levels relative to well-mixed marine air are observed during periods of offshore winds at coastal sensor platforms in Monterey Bay, California, USA. The highest concentrations originate from urban and agricultural areas, are driven by diurnal winds, and peak in the early morning. These enhanced atmospheric levels can be detected across a ~100km wide nearshore area and represent a significant addition to total oceanic CO2 uptake. A global estimate puts the added sea-air flux of CO2 from these greatly enhanced atmospheric CO2 levels at 25 million tonnes, roughly 1% of the ocean’s annual CO2 uptake. The increased uptake over the 100 km coastal swath is of order 20%, indicating a potentially large impact on ocean acidification in productive coastal waters. [ABSTRACT FROM AUTHOR]

Provides information on a study which applied a modified plankton model to the coastal upwelling ecosystem of Monterey Bay, California. Environmental setting; Details on the model; Results of the study.

Provides information on a study which estimated primary production using phytoplankton utilization of nitrate for the Monterey Bay, California region. Model description; Results and discussion.

Offers the results of a study on the connection between the deaths of sea lions along the central California coast and a bloom of Pseudo nitzschia australis, or diatom, during the same time span. Association of the bloom with production of domoic acid (DA), a neurotoxin; Sea lions as showing evidence of neurological dysfunction; Display of little or no amounts of DA in other marine life; Implications for the use of toxicity levels of mussels to provide adequate warning for marine wildlife and humans.

Examines the turbid underflows from a coastal river into the deep sea in Monterey Bay, California. Inferences from the structure of coastal sedimentary deposits; Observations of turbidity in deep water during high river flows; Causes of driving hyperpycnal flows of turbid freshwater into depth.

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: This paper investigates the transport structure of surface currents around the Monterey Bay, CA region. Currents measured by radar stations around Monterey Bay indicate the presence of strong, spatial and temporal, nonlinear patterns. To understand the geometry of the flow in the bay, Lagrangian coherent structures (LCS) are computed. These structures are mobile separatrices that divide the flow into regions of qualitatively different dynamics. They provide direct information about the flow structure but are geometrically simpler than particle trajectories themselves. The LCS patterns were used to reveal the mesoscale flow conditions observed during the 2003 Autonomous Ocean Sampling Network (AOSN-II) experiment. Drifter paths from the AOSN experiment were compared to the patterns induced by the LCS computed from high-frequency radar data. We verify that the fate of the drifters can be better characterized based on the LCS than direct interpretation of the current data. This property can be exploited to optimize drifter deployment. [Copyright &y& Elsevier]

We report results of ecosystem studies in Monterey Bay, California, during the summer upwelling periods, 1996–99, including impacts of El Nin˜o 1997–98 and La Nin˜a 1999. Random-systematic line-transect surveys of marine mammals were conducted monthly from August to November 1996, and from May to November 1997–99. CTDs and zooplankton net tows were conducted opportunistically, and at 10 predetermined locations. Hydroacoustic backscatter was measured continuously while underway to estimate prevalence of zooplankton, with emphasis on euphausiids, a key trophic link between primary production and higher trophic level consumers.The occurrences of several of the California Current’s most common cetaceans varied among years. The assemblage of odontocetes became more diverse during the El Nin˜o with a temporary influx of warm-water species. Densities of cold-temperate Dall’s porpoise, Phocoenoides dalli, were greatest before the onset of El Nin˜o, whereas warm-temperate common dolphins, Delphinus spp., were present only during the warm-water period associated with El Nin˜o. Rorqual densities decreased in August 1997 as euphausiid backscatter was reduced. In 1998, as euphausiid backscatter slowly increased, rorqual densities increased sharply to the greatest observed values. Euphausiid backscatter further increased in 1999, whereas rorqual densities were similar to those observed during 1998. We hypothesize that a dramatic reduction in zooplankton biomass offshore during El Nin˜o 1997–98 led to the concentration of rorquals in the remaining productive coastal upwelling areas, including Monterey Bay. These patterns exemplify short-term responses of cetaceans to large-scale changes in oceanic conditions. [Copyright &y& Elsevier]