Coastal Oceanography

Coastal oceanography at BML includes both physical (John Largier and Tessa Hill) and biological (Steven Morgan) aspects. The physical forcing in the coastal ocean on the North-Central coast is a topic of great interest and by nature is an interdisciplinary scientific problem.

Physical Oceanography

chl + currents

Physical coastal oceanography research at BML focuses on ocean upwelling, land runoff, and the connections between coastal estuaries (both small and large) and the ocean. Coastal oceanography at the land-sea interface is a unique niche in oceanography and there is little doubt that the Coastal Oceanography Group (COG), led by John Largier, is highly productive at both regional and national/international levels. The COG focuses on regional place-based research along the north coast of California, taking advantage of the unique ocean upwelling zone, as well as in comparable regions globally. With new as well as continued collaborations with biologists and modelers, and with diverse funding for this research, the COG has made a major impact on our understanding of coastal processes at both the basic physical oceanography level as well as the applied coastal management level.

The Bodega Marine Laboratory’s Coastal Oceanography Program is directed at the emerging discipline of “environmental oceanography,” in which oceanographic study, analysis and insight is directed at resolving environmental issues that are critical to the sustainable interaction between human society and our planet. The ocean off BML is renowned for strong winds that draw cold nutrient-rich water up to sunlit ocean surfaces and support one of the earth’s most productive marine ecosystems. BML scientists examine how oceanographic and atmospheric processes shape the environment and influence the distribution and growth of marine organisms along the coast. Studies address marine fisheries, atmospheric processes, Marine Protected Areas, carbon and nitrogen cycles, land runoff and water quality in coastal waters. This research utilizes BML’s environmental sensor network, the Bodega Ocean Observing Node (BOON), and state-of-the-art research vessel, the R/V Mussel Point.

Research areas include:

Coastal Upwelling

BML is located in the center of the California upwelling system, with the strongest and most persistent winds anywhere along the west coast of North America. It is logical then that researchers are leaders in the science of wind-driven coastal upwelling, and how it yields such a rich ecosystem. Ongoing studies and research campaigns yield new insight year after year – on physical processes, plankton productivity, and ecosystem connectivity.  At the heart of this research is the custom research vessel the R/V Mussel Point that allows researchers to quickly and safely travel offshore to probe the physics, biology and chemistry of this fertile ecosystem. Upwelling Oceanography focuses on addressing small-scale patterns in coastal upwelling, both spatial (e.g., cape-and-bay) and temporal (e.g. , upwelling-relaxation); emphasis on features and processes that play a primary role in ecosystem productivity (plankton communities) and the connectivity of coastal populations (larval dispersal).

Estuaries and Land Runoff

As part of the hydrological cycle, freshwater runs off the land and into the ocean – fueling ocean ecosystems with food and nutrients as well as affecting currents and stratification in coastal waters. Changes in the volume and timing of this runoff, as well as in the particulate and dissolved load, have a profound effect on coastal and estuarine waters with impacts on fisheries, ecosystems, wildlife and human health. BML research is focused on west-coast estuaries and river plumes, notably addressing estuaries with seasonal inflow (little runoff during long dry summers) and estuaries with wave-built sand barriers across their mouths. Runoff Oceanography focuses on addressing the role of land runoff in shaping estuaries (e.g., bar-built and low-inflow estuaries) and nearshore waters (i.e. , river plumes); emphasis on flow features and processes that exert control on estuarine habitats and coastal pollution.

Nearshore Oceanography and Hydrodynamics

The peculiarities of how coastal currents change close to the shore is a surprisingly recent field of research and one in which several BML researchers are active, using approaches that include mathematics and field-observations. The study of internal waves dissipating nearshore, the slowing of currents in the coastal boundary layer, the breaking of waves on the shore, and the retention of waters in small coves and bays is understood within a broader view of nearshore ecology and environmental issues. Nearshore Oceanography focuses on addressing the coupling between the ocean and the shoreline (i.e. , how material and energy are exchanged); with strong links to companion themes of upwelling and land runoff.

Ocean Observing Systems

Ocean temperature and salinity has been recorded daily at BML for over 50 years, and for a couple of decades additional data on winds, chlorophyll, weather and currents have been collected. BML is a leading member of the national Integrated Ocean Observing System, and the regional association Central and Northern California Ocean Observing System (CeNCOOS). Data are displayed and available via the Bodega Ocean Observing Node (BOON). In addition to the operational system that includes a permanent mooring a mile offshore and provides hourly surface data at distances over 100 miles offshore, BML provides leadership in the use of these data to better understand the ocean, specifically relating new insights to ecology and environmental science.

These areas of coastal oceanography research are all highly interdisciplinary and include other BML researchers, campus faculty, and researchers from other institutions.

Larval Dispersal and Biological Oceanography

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Professor Steven Morgan has developed key areas in coastal oceanography and larval biology at BML that are critical to the State’s needs and their priorities. His strong collaborations with the COG is one of the key examples of interdisciplinary science at BML. Examples include: 1) interdisciplinary projects investigating the linkages of ecological processes with physical oceanography in estuarine and ocean ecosystems in order to understand larval transport; 2) establishing and developing approaches for evaluating marine protected areas along the California coast; 3) use of resident sentinel species for assessing ecosystem health that include contaminant impacts on early life stages of indigenous invertebrates and vertebrates; and 4) the lead scientists who established the “Bodega Line”, a cross-continental shelf multidisciplinary monitoring effort that examines the physical forces on the productivity of the coastal ecosystem and directly forecasts year-class strength in critical species such as salmon.

Steven Morgan and BML researchers are at the forefront of using oceanographic data to better understand and quantify the dispersal of larvae in coastal upwelling ecosystems. In particular, hourly maps of surface currents obtained from an array of HF radar stations have proved invaluable in the assessment of connectivity between nearshore adult habitats. Oceanographers and ecologists at BML work closely to develop an integrated view of larval ecology.

Professor Morgan’s research has shown conclusively that the larval behavior of marine organisms effectively maintains them on the shelf and regulates recruitment back to adult habitats in spite of the strong persistent winds that prevail along the North coast of California. Portions of this research was published in the Proceedings of the National Academy of Sciences USA. These findings essentially overturn the long-standing ecological paradigm that larval recruitment in upwelling regions are regulated to the extent that prevailing winds move larvae out to sea. Professor Morgan has shown that reproductive timing is key to survival of larvae in upwelling regions. He has also demonstrated that indigenous organisms can be used to determine ecosystem health in coastal and marine environments.