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• 1. [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

• 2. [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

• 3. [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

• 4. [Article] Wave-Driven Inner-Shelf Motions on the Oregon Coast*

  Recent work by S. Lentz et al. documents offshore transport in the inner shelf due to a wave-driven return flow associated with the Hasselmann wave stress (the Stokes–Coriolis force). This analysis is ...

  Citation × Citation Citation Abstract Copy Title: Wave-Driven Inner-Shelf Motions on the Oregon Coast* Author: Kirincich, Anthony R., Barth, John A., Lentz, Steven J. Recent work by S. Lentz et al. documents offshore transport in the inner shelf due to a wave-driven return flow associated with the Hasselmann wave stress (the Stokes–Coriolis force). This analysis is extended using observations from the central Oregon coast to identify the wave-driven return flow present and quantify the potential bias of wind-driven across-shelf exchange by unresolved wave-driven circulation. Using acoustic Doppler current profiler (ADCP) measurements at six stations, each in water depths of 13–15 m, observed depth-averaged, across-shelf velocities were generally correlated with theoretical estimates of the proposed return flow. During times of minimal wind forcing, across-shelf velocity profiles were vertically sheared, with stronger velocities near the top of the measured portion of the water column, and increased in magnitude with increasing significant wave height, consistent with circulation due to the Hasselmann wave stress. Yet velocity magnitudes and vertical shears were stronger than that predicted by linear wave theory, and more similar to the stratified ‘‘summer’’ velocity profiles described by S. Lentz et al. Additionally, substantial temporal and spatial variability of the wave-driven return flow was found, potentially due to changing wind and wave conditions as well as local bathymetric variability. Despite the wave-driven circulation found, subtracting estimates of the return flow from the observed across-shelf velocity had no significant effect on estimates of the across-shelf exchange due to along-shelf wind forcing at these water depths along the Oregon coast during summer. Title: Wave-Driven Inner-Shelf Motions on the Oregon Coast* Author: Kirincich, Anthony R., Barth, John A., Lentz, Steven J. Recent work by S. Lentz et al. documents offshore transport in the inner shelf due to a wave-driven return flow associated with the Hasselmann wave stress (the Stokes–Coriolis force). This analysis is extended using observations from the central Oregon coast to identify the wave-driven return flow present and quantify the potential bias of wind-driven across-shelf exchange by unresolved wave-driven circulation. Using acoustic Doppler current profiler (ADCP) measurements at six stations, each in water depths of 13–15 m, observed depth-averaged, across-shelf velocities were generally correlated with theoretical estimates of the proposed return flow. During times of minimal wind forcing, across-shelf velocity profiles were vertically sheared, with stronger velocities near the top of the measured portion of the water column, and increased in magnitude with increasing significant wave height, consistent with circulation due to the Hasselmann wave stress. Yet velocity magnitudes and vertical shears were stronger than that predicted by linear wave theory, and more similar to the stratified ‘‘summer’’ velocity profiles described by S. Lentz et al. Additionally, substantial temporal and spatial variability of the wave-driven return flow was found, potentially due to changing wind and wave conditions as well as local bathymetric variability. Despite the wave-driven circulation found, subtracting estimates of the return flow from the observed across-shelf velocity had no significant effect on estimates of the across-shelf exchange due to along-shelf wind forcing at these water depths along the Oregon coast during summer. Close

• 5. [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

• 6. [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

• 7. [Article] Flow-topography interactions in the northern California Current System observed from geostationary satellite data

  copyrighted by American Geophysical Union

  Citation × Citation Citation Abstract Copy Title: Flow-topography interactions in the northern California Current System observed from geostationary satellite data Author: Castelao, Renato M., Mavor, Timothy P., Barth, John A. copyrighted by American Geophysical Union Title: Flow-topography interactions in the northern California Current System observed from geostationary satellite data Author: Castelao, Renato M., Mavor, Timothy P., Barth, John A. copyrighted by American Geophysical Union Close

• 8. [Article] Time-dependent, wind-driven flow over a shadow midshelf submarine bank

  copyrighted by American Geophysical Union

  Citation × Citation Citation Abstract Copy Title: Time-dependent, wind-driven flow over a shadow midshelf submarine bank Author: Castelao, R. M., Pierce, S. D., Barth, John A. copyrighted by American Geophysical Union Title: Time-dependent, wind-driven flow over a shadow midshelf submarine bank Author: Castelao, R. M., Pierce, S. D., Barth, John A. copyrighted by American Geophysical Union Close

• 9. [Article] Declining Oxygen in the Northeast Pacific

  This is the publisher’s final pdf. The published article is copyrighted by the American Meteorological Society and can be found at: http://journals.ametsoc.org/loi/phoc.

  Citation × Citation Citation Abstract Copy Title: Declining Oxygen in the Northeast Pacific Author: Shearman, R. Kipp, Pierce, Stephen D., Erofeev, Anatoli Y., Barth, John A. This is the publisher’s final pdf. The published article is copyrighted by the American Meteorological Society and can be found at: http://journals.ametsoc.org/loi/phoc. Title: Declining Oxygen in the Northeast Pacific Author: Shearman, R. Kipp, Pierce, Stephen D., Erofeev, Anatoli Y., Barth, John A. This is the publisher’s final pdf. The published article is copyrighted by the American Meteorological Society and can be found at: http://journals.ametsoc.org/loi/phoc. Close

• 10. [Article] Direct Observations of Along-Isopycnal Upwelling and Diapycnal Velocity at a Shelfbreak Front

  By mapping the three-dimensional density field while simultaneously tracking a subsurface, isopycnal float, direct observations of upwelling along a shelfbreak front were made on the southern flank of ...

  Citation × Citation Citation Abstract Copy Title: Direct Observations of Along-Isopycnal Upwelling and Diapycnal Velocity at a Shelfbreak Front Author: Hebert, Dave, Dale, Andrew C., Barth, John A., Ullman, David S. By mapping the three-dimensional density field while simultaneously tracking a subsurface, isopycnal float, direct observations of upwelling along a shelfbreak front were made on the southern flank of Georges Bank. The thermohaline and bio-optical fields were mapped using a towed undulating vehicle, and horizontal velocity was measured with a shipboard acoustic Doppler current profiler. A subsurface isopycnal float capable of measuring diapycnal flow past the float was acoustically tracked from the ship. The float was released near the foot of the shelfbreak front (95–100-m isobath) and moved 15 km seaward as it rose from 80 to 50 m along the sloping frontal isopycnals over a 2-day deployment. The float's average westward velocity was 0.09 m s⁻¹, while a drifter drogued at 15 m released at the same location moved westward essentially alongfront at 0.18 m s⁻¹. The float measured strong downward vertical velocities (in excess of 0.02 m s−¹) associated with propagation of internal tidal solibores in the onbank direction from their formation near the shelf break. The float measured large upward vertical velocities (in excess of 0.001 m s⁻¹ 100 m day⁻¹) as the pycnocline rebounded adiabatically after the passage of the internal tide solibore. The directly measured mean along-isopycnal vertical velocity was 17.5 m day⁻¹. Intense mixing events lasting up to 2 hours were observed in the shelfbreak front at the boundary between cold, fresh shelf water and warm, salty slope water. Diapycnal velocities of up to 3 × 10⁻³ m s⁻¹ were measured, implying a diapycnal thermal diffusivity as large as 10⁻² m2 s⁻¹, indicative of strong mixing events in this coastal front. Title: Direct Observations of Along-Isopycnal Upwelling and Diapycnal Velocity at a Shelfbreak Front Author: Hebert, Dave, Dale, Andrew C., Barth, John A., Ullman, David S. By mapping the three-dimensional density field while simultaneously tracking a subsurface, isopycnal float, direct observations of upwelling along a shelfbreak front were made on the southern flank of Georges Bank. The thermohaline and bio-optical fields were mapped using a towed undulating vehicle, and horizontal velocity was measured with a shipboard acoustic Doppler current profiler. A subsurface isopycnal float capable of measuring diapycnal flow past the float was acoustically tracked from the ship. The float was released near the foot of the shelfbreak front (95–100-m isobath) and moved 15 km seaward as it rose from 80 to 50 m along the sloping frontal isopycnals over a 2-day deployment. The float's average westward velocity was 0.09 m s⁻¹, while a drifter drogued at 15 m released at the same location moved westward essentially alongfront at 0.18 m s⁻¹. The float measured strong downward vertical velocities (in excess of 0.02 m s−¹) associated with propagation of internal tidal solibores in the onbank direction from their formation near the shelf break. The float measured large upward vertical velocities (in excess of 0.001 m s⁻¹ 100 m day⁻¹) as the pycnocline rebounded adiabatically after the passage of the internal tide solibore. The directly measured mean along-isopycnal vertical velocity was 17.5 m day⁻¹. Intense mixing events lasting up to 2 hours were observed in the shelfbreak front at the boundary between cold, fresh shelf water and warm, salty slope water. Diapycnal velocities of up to 3 × 10⁻³ m s⁻¹ were measured, implying a diapycnal thermal diffusivity as large as 10⁻² m2 s⁻¹, indicative of strong mixing events in this coastal front. Close