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• 1. [Article] New Insights into the Controls and Mechanisms of Plankton Productivity Along the US West Coast

  During the lifetime of the National Science Foundation's Coastal Ocean Processes program, four experiments were conducted on the US West Coast in the northern California Current System. Although each project ...

  Citation × Citation Citation Abstract Copy Title: New Insights into the Controls and Mechanisms of Plankton Productivity Along the US West Coast Author: Kudela, Raphael M., Banas, Neil S., Barth, John A., Frame, Elizabeth R., Jay, David A., Largier, John L., Lessard, Evelyn J., Peterson, Tawnya D., Vander Woude, Andrea J. Year: 2008 During the lifetime of the National Science Foundation's Coastal Ocean Processes program, four experiments were conducted on the US West Coast in the northern California Current System. Although each project had a unique scientific focus, all four addressed the mechanisms causing eastern boundary current systems in general, and the California Current System in particular, to be biologically rich, from phytoplankton to apex predators. Taken together, findings from these projects provide new insights into the canonical view that upwelling systems are simple wind-driven "conveyor belts," bringing cold, nutrient-rich waters to the well-lit surface ocean where biological organisms flourish. We highlight new insights and advances gained from these programs, including recognition that (a) elements other than nitrogen, particularly iron, may limit the base of the food chain, and (b) the source of these nutrients is not solely a result of wind-driven Ekman transport. The importance of retentive features has clearly emerged, whether these are associated with topography, bathymetry, or more transient features such as river plumes. These new insights into the drivers and fate of this high biological productivity should greatly improve current and future generations of ecosystem models and provide a better understanding of the unique physical-biological coupling that makes the California Current System so rich. Title: New Insights into the Controls and Mechanisms of Plankton Productivity Along the US West Coast Author: Kudela, Raphael M., Banas, Neil S., Barth, John A., Frame, Elizabeth R., Jay, David A., Largier, John L., Lessard, Evelyn J., Peterson, Tawnya D., Vander Woude, Andrea J. Year: 2008 During the lifetime of the National Science Foundation's Coastal Ocean Processes program, four experiments were conducted on the US West Coast in the northern California Current System. Although each project had a unique scientific focus, all four addressed the mechanisms causing eastern boundary current systems in general, and the California Current System in particular, to be biologically rich, from phytoplankton to apex predators. Taken together, findings from these projects provide new insights into the canonical view that upwelling systems are simple wind-driven "conveyor belts," bringing cold, nutrient-rich waters to the well-lit surface ocean where biological organisms flourish. We highlight new insights and advances gained from these programs, including recognition that (a) elements other than nitrogen, particularly iron, may limit the base of the food chain, and (b) the source of these nutrients is not solely a result of wind-driven Ekman transport. The importance of retentive features has clearly emerged, whether these are associated with topography, bathymetry, or more transient features such as river plumes. These new insights into the drivers and fate of this high biological productivity should greatly improve current and future generations of ecosystem models and provide a better understanding of the unique physical-biological coupling that makes the California Current System so rich. Close

• 2. [Article] Anomalously warm July 2005 in the northern California Current : historical context and the significance of cumulative wind stress

  copyrighted by American Geophysical Union

  Citation × Citation Citation Abstract Copy Title: Anomalously warm July 2005 in the northern California Current : historical context and the significance of cumulative wind stress Author: Fleischer, Guy W., Pierce, Stephen D., Thomas, Rebecca E., Barth, John A. copyrighted by American Geophysical Union Title: Anomalously warm July 2005 in the northern California Current : historical context and the significance of cumulative wind stress Author: Fleischer, Guy W., Pierce, Stephen D., Thomas, Rebecca E., Barth, John A. copyrighted by American Geophysical Union Close

• 3. [Article] The front on the northern flank of Georges Bank in spring : 1. tidal and subtidal variability

  copyrighted by American Geophysical Union

  Citation × Citation Citation Abstract Copy Title: The front on the northern flank of Georges Bank in spring : 1. tidal and subtidal variability Author: Hebert, Dave, Dale, Andrew C., Barth, John A., Ullman, David S. copyrighted by American Geophysical Union Title: The front on the northern flank of Georges Bank in spring : 1. tidal and subtidal variability Author: Hebert, Dave, Dale, Andrew C., Barth, John A., Ullman, David S. copyrighted by American Geophysical Union Close

• 4. [Article] Coastal ocean response to summer upwelling favorable winds in a region of alongshore bottom topography variations off Oregon

  copyrighted by American Geophysical Union

  Citation × Citation Citation Abstract Copy Title: Coastal ocean response to summer upwelling favorable winds in a region of alongshore bottom topography variations off Oregon Author: Castelao, Renato M., Barth, John A. copyrighted by American Geophysical Union Title: Coastal ocean response to summer upwelling favorable winds in a region of alongshore bottom topography variations off Oregon Author: Castelao, Renato M., Barth, John A. copyrighted by American Geophysical Union Close

• 5. [Article] Mesoscale physical and bio-optical structure of the Antarctic Polar Front near 170°W during austral spring

  copyrighted by American Geophysical Union

  Citation × Citation Citation Abstract Copy Title: Mesoscale physical and bio-optical structure of the Antarctic Polar Front near 170°W during austral spring Author: Cowles, Timothy J., Barth, John A., Pierce, Stephen D. copyrighted by American Geophysical Union Title: Mesoscale physical and bio-optical structure of the Antarctic Polar Front near 170°W during austral spring Author: Cowles, Timothy J., Barth, John A., Pierce, Stephen D. copyrighted by American Geophysical Union Close

• 6. [Article] Short-wavelength instabilities on coastal jets and fronts

  copyrighted by American Geophysical Union

  Citation × Citation Citation Abstract Copy Title: Short-wavelength instabilities on coastal jets and fronts Author: Barth, John A. copyrighted by American Geophysical Union Title: Short-wavelength instabilities on coastal jets and fronts Author: Barth, John A. copyrighted by American Geophysical Union Close

• 7. [Article] Diagnosis of the Three-Dimensional Circulation Associated with Mesoscale Motion in the California Current

  A high-resolution upper-ocean survey of a cyclonic jet meander and an adjacent cyclonic eddy in the California Current region near 38°N, 126°W was conducted as part of the summer of 1993 Eastern Boundary ...

  Citation × Citation Citation Abstract Copy Title: Diagnosis of the Three-Dimensional Circulation Associated with Mesoscale Motion in the California Current Author: Shearman, R. Kipp, Kosro, P. Michael, Barth, John A. A high-resolution upper-ocean survey of a cyclonic jet meander and an adjacent cyclonic eddy in the California Current region near 38°N, 126°W was conducted as part of the summer of 1993 Eastern Boundary Currents program. Temperature and salinity were measured from a SeaSoar vehicle, and velocity was measured by shipboard acoustic Doppler current profiler (ADCP). SeaSoar data show a density front at a depth of 70–100 m with strong cyclonic curvature. The geostrophic velocity fields, referenced to the ADCP data at 200 m, show a strong surface-intensified jet (maximum speed of 0.9 m s⁻¹) that follows the density front along a cyclonic meander. Relative vorticities within the jet are large, ranging from −0.8ƒ to +1.2ƒ, where ƒ is the local Coriolis parameter. The SeaSoar density and ADCP velocity data are used to diagnose the vertical velocity via the Q-vector form of the quasigeostrophic omega equation. The diagnosed vertical velocity field shows a maximum speed of 40–45 m d⁻¹. The lateral distribution of vertical velocity is characterized by two length scales: a large (~75 km) pattern where there is downwelling upstream and upwelling downstream of the cyclonic bend, and smaller patches arrayed along the jet core with diameters of 20–30 km. Geostrophic streamline analysis of vertical velocity indicates that water parcels make net vertical excursions of 20–30 m over 2–3 days, resulting in net vertical velocities of 7–15 m d⁻¹. Water parcels moving along geostrophic streamlines experience maximum vertical velocities in the regions of maximum alongstream change in relative vorticity, an indication of potential vorticity conservation. Title: Diagnosis of the Three-Dimensional Circulation Associated with Mesoscale Motion in the California Current Author: Shearman, R. Kipp, Kosro, P. Michael, Barth, John A. A high-resolution upper-ocean survey of a cyclonic jet meander and an adjacent cyclonic eddy in the California Current region near 38°N, 126°W was conducted as part of the summer of 1993 Eastern Boundary Currents program. Temperature and salinity were measured from a SeaSoar vehicle, and velocity was measured by shipboard acoustic Doppler current profiler (ADCP). SeaSoar data show a density front at a depth of 70–100 m with strong cyclonic curvature. The geostrophic velocity fields, referenced to the ADCP data at 200 m, show a strong surface-intensified jet (maximum speed of 0.9 m s⁻¹) that follows the density front along a cyclonic meander. Relative vorticities within the jet are large, ranging from −0.8ƒ to +1.2ƒ, where ƒ is the local Coriolis parameter. The SeaSoar density and ADCP velocity data are used to diagnose the vertical velocity via the Q-vector form of the quasigeostrophic omega equation. The diagnosed vertical velocity field shows a maximum speed of 40–45 m d⁻¹. The lateral distribution of vertical velocity is characterized by two length scales: a large (~75 km) pattern where there is downwelling upstream and upwelling downstream of the cyclonic bend, and smaller patches arrayed along the jet core with diameters of 20–30 km. Geostrophic streamline analysis of vertical velocity indicates that water parcels make net vertical excursions of 20–30 m over 2–3 days, resulting in net vertical velocities of 7–15 m d⁻¹. Water parcels moving along geostrophic streamlines experience maximum vertical velocities in the regions of maximum alongstream change in relative vorticity, an indication of potential vorticity conservation. Close

• 8. [Article] Northern Monterey Bay upwelling shadow front : observations of a coastally and surface-trapped bouyant plume

  copyrighted by American Geophysical Union

  Citation × Citation Citation Abstract Copy Title: Northern Monterey Bay upwelling shadow front : observations of a coastally and surface-trapped bouyant plume Author: Ryan, J. P., Washburn, L., Hoover, D. J., Tyburczy, J., Barth, John A., McManus, M. A., Kirinicich, A. R., Woodson, C. B. copyrighted by American Geophysical Union Title: Northern Monterey Bay upwelling shadow front : observations of a coastally and surface-trapped bouyant plume Author: Ryan, J. P., Washburn, L., Hoover, D. J., Tyburczy, J., Barth, John A., McManus, M. A., Kirinicich, A. R., Woodson, C. B. copyrighted by American Geophysical Union Close

• 9. [Article] Wind-driven inner-shelf circulation off central Oregon during summer

  copyrighted by American Geophysical Union

  Citation × Citation Citation Abstract Copy Title: Wind-driven inner-shelf circulation off central Oregon during summer Author: Menge, Bruce A., Lubchenco, Jane, Kirincich, Anthony R., Grantham, Brian A., Barth, John A. copyrighted by American Geophysical Union Title: Wind-driven inner-shelf circulation off central Oregon during summer Author: Menge, Bruce A., Lubchenco, Jane, Kirincich, Anthony R., Grantham, Brian A., Barth, John A. copyrighted by American Geophysical Union Close

• 10. [Article] The nature of the cold filaments in the California current system

  Data from the Coastal Transition Zone (CTZ) experiment are used to describe the velocity fields and water properties associate with cold filaments in the California Current. Combined with previous field ...

  Citation × Citation Citation Abstract Copy Title: The nature of the cold filaments in the California current system Author: Mackas, D. L., Swenson, M., Chavez, F., James, C., Batteen, M., Strub, P. Ted, Kadko, D., Abbott, Mark R., Hayward, T., Dewey, R., Ramp, S., Brink, K. H., Niiler, Pearn P., Huyer, Adriana, 1945-, Kosro, P. Michael, 1951-, Haidvogel, D., Barber, R., Haney, R., Walstad, L., Hood, R. R., Barth, John A., Washburn, L. A. Data from the Coastal Transition Zone (CTZ) experiment are used to describe the velocity fields and water properties associate with cold filaments in the California Current. Combined with previous field surveys and satellite imagery, these show seasonal variability with maximum dynamic height ranges and velocities in summer and minimum values in late winter and early spring. North of Point Arenda (between 39ºN and 42ºN) in spring–summer the flow field on the outer edge of the cold water has the character of a meandering jet, carrying fresh, nutrient-poor water from farther north on its offshore side and cold, salty, nutrient-rich water on its inshore side. At Point Arena in midsummer, the jet often flows offshore and continues south without meandering back onshore as strongly as it does farther north. The flow field south of Point Arena in summer takes on more of the character of a field of mesoscale eddies, although the meandering jet from the north continues to be identifiable. The conceptual model for the May–July period between 36ºN and 42ºN is thus of a surface jet that meanders through and interacts with a field of eddies; the eddies are more dominant south of 39ºN, where the jet broadens and where multiple jets and filaments are often present. At the surface, the jet often separates biological communities and may appear as a barrier to cross-jet transport, especially north of Point Arena early in the season (March–May) However, phytoplankton pigment and nutrients are carried on the inshore flank of the jet, and pigment maxima are sometimes found in the core of the jet. The biological effect of the jet is to define a convoluted, 100 to 400-km-wide region next to the coast, within which much of the richer water is contained, and also to carry some of that richer water offshore in meanders along the outer edge of that region. Title: The nature of the cold filaments in the California current system Author: Mackas, D. L., Swenson, M., Chavez, F., James, C., Batteen, M., Strub, P. Ted, Kadko, D., Abbott, Mark R., Hayward, T., Dewey, R., Ramp, S., Brink, K. H., Niiler, Pearn P., Huyer, Adriana, 1945-, Kosro, P. Michael, 1951-, Haidvogel, D., Barber, R., Haney, R., Walstad, L., Hood, R. R., Barth, John A., Washburn, L. A. Data from the Coastal Transition Zone (CTZ) experiment are used to describe the velocity fields and water properties associate with cold filaments in the California Current. Combined with previous field surveys and satellite imagery, these show seasonal variability with maximum dynamic height ranges and velocities in summer and minimum values in late winter and early spring. North of Point Arenda (between 39ºN and 42ºN) in spring–summer the flow field on the outer edge of the cold water has the character of a meandering jet, carrying fresh, nutrient-poor water from farther north on its offshore side and cold, salty, nutrient-rich water on its inshore side. At Point Arena in midsummer, the jet often flows offshore and continues south without meandering back onshore as strongly as it does farther north. The flow field south of Point Arena in summer takes on more of the character of a field of mesoscale eddies, although the meandering jet from the north continues to be identifiable. The conceptual model for the May–July period between 36ºN and 42ºN is thus of a surface jet that meanders through and interacts with a field of eddies; the eddies are more dominant south of 39ºN, where the jet broadens and where multiple jets and filaments are often present. At the surface, the jet often separates biological communities and may appear as a barrier to cross-jet transport, especially north of Point Arena early in the season (March–May) However, phytoplankton pigment and nutrients are carried on the inshore flank of the jet, and pigment maxima are sometimes found in the core of the jet. The biological effect of the jet is to define a convoluted, 100 to 400-km-wide region next to the coast, within which much of the richer water is contained, and also to carry some of that richer water offshore in meanders along the outer edge of that region. Close