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• 1. [Article] Occurrence of demersal fishes in relation to near-bottom oxygen levels within the California Current large marine ecosystem

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by John Wiley ...

  Citation × Citation Citation Abstract Copy Title: Occurrence of demersal fishes in relation to near-bottom oxygen levels within the California Current large marine ecosystem Author: Ciannelli, Lorenzo, Pierce, Stephen D., Wakefield, W. Waldo, Simon, Victor, Keller, Aimee A., Barth, John A. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by John Wiley & Sons Ltd. and can be found at: http://onlinelibrary.wiley.com/journal/10.1111/%28ISSN%291365-2419. Title: Occurrence of demersal fishes in relation to near-bottom oxygen levels within the California Current large marine ecosystem Author: Ciannelli, Lorenzo, Pierce, Stephen D., Wakefield, W. Waldo, Simon, Victor, Keller, Aimee A., Barth, John A. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by John Wiley & Sons Ltd. and can be found at: http://onlinelibrary.wiley.com/journal/10.1111/%28ISSN%291365-2419. 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] SeaSoar CTD observations during the coastal mixing and optics experiment : R/V Endeavor cruises from 14-Aug to 1-Sep 1996 and 25-Apr to 15-May 1997

  Citation × Citation Citation Abstract Copy Title: SeaSoar CTD observations during the coastal mixing and optics experiment : R/V Endeavor cruises from 14-Aug to 1-Sep 1996 and 25-Apr to 15-May 1997 Author: Kosro, P. Michael, 1951-, Oregon State University. College of Oceanic and Atmospheric Sciences, O'Malley, Robert T., Erofeev, A. Y. (Anatoli Y.), Barth, John A., Pierce, Stephen D., Fleischbein, Jane Title: SeaSoar CTD observations during the coastal mixing and optics experiment : R/V Endeavor cruises from 14-Aug to 1-Sep 1996 and 25-Apr to 15-May 1997 Author: Kosro, P. Michael, 1951-, Oregon State University. College of Oceanic and Atmospheric Sciences, O'Malley, Robert T., Erofeev, A. Y. (Anatoli Y.), Barth, John A., Pierce, Stephen D., Fleischbein, Jane Close

• 4. [Article] Structure and dynamics of a coastal filament

  Copyrighted by American Geophysical Union.

  Citation × Citation Citation Abstract Copy Title: Structure and dynamics of a coastal filament Author: Dewey, Richard K., Paulson, Clayton A., Caldwell, Douglas R., Pierce, Stephen D., Moum, James N. Copyrighted by American Geophysical Union. Title: Structure and dynamics of a coastal filament Author: Dewey, Richard K., Paulson, Clayton A., Caldwell, Douglas R., Pierce, Stephen D., Moum, James N. Copyrighted by American Geophysical Union. Close

• 5. [Article] Physical versus biological spring transition: 2005

  In 2005, the onset of spring conditions in the physics of the coastal ocean (lowered sea level, spin-up of vertically-sheared equatorward coastal jet) came about 50 days later than average off Newport ...

  Citation × Citation Citation Abstract Copy Title: Physical versus biological spring transition: 2005 Author: Shearman, R. Kipp, Hickey, Barbara M., Pierce, Stephen D., Peterson, William T., Kosro, P. Michael, 1951- In 2005, the onset of spring conditions in the physics of the coastal ocean (lowered sea level, spin-up of vertically-sheared equatorward coastal jet) came about 50 days later than average off Newport Oregon, on May 24. There was a further delay of 50 days before the subsurface upwelled water penetrated into the anomalously stratified surface layer, becoming most available for biological activity. The warm anomaly in sea surface temperature which provided the surface cap was observed at mid-shelf locations from Washington to central California, but it ended sooner south of Oregon. Biological impacts of these delays to several trophic levels have been reported. Title: Physical versus biological spring transition: 2005 Author: Shearman, R. Kipp, Hickey, Barbara M., Pierce, Stephen D., Peterson, William T., Kosro, P. Michael, 1951- In 2005, the onset of spring conditions in the physics of the coastal ocean (lowered sea level, spin-up of vertically-sheared equatorward coastal jet) came about 50 days later than average off Newport Oregon, on May 24. There was a further delay of 50 days before the subsurface upwelled water penetrated into the anomalously stratified surface layer, becoming most available for biological activity. The warm anomaly in sea surface temperature which provided the surface cap was observed at mid-shelf locations from Washington to central California, but it ended sooner south of Oregon. Biological impacts of these delays to several trophic levels have been reported. Close

• 6. [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

• 7. [Article] Currents and water masses of the coastal transition zone off Northern California, June to August 1988

  In summer 1988, we made repeated mesoscale surveys of a grid extending 200 km offshore between 37°N and 39°N in the coastal transition zone off northern California, obtaining continuous acoustic Doppler ...

  Citation × Citation Citation Abstract Copy Title: Currents and water masses of the coastal transition zone off Northern California, June to August 1988 Author: Ramp, Steven R., Washburn, Libe, Cowles, Timothy J., Fleischbein, Jane, Stanton, Tim, Huyer, Adriana, 1945-, Kosro, P. Michael, 1951-, Smith, Robert L. (Robert Lloyd), 1935-, Pierce, Stephen D., Chavez, Francisco P. In summer 1988, we made repeated mesoscale surveys of a grid extending 200 km offshore between 37°N and 39°N in the coastal transition zone off northern California, obtaining continuous acoustic Doppler current profiler data and conductivity-temperature-depth data at standard stations 25 km apart on alongshore sections 40 km apart. All surveys showed a baroclinic equatorward jet, with core velocities of >50 cm/s at the surface decreasing to about 10 cm/s at 200m , a width of 50-75 km, and a baroclinic transporotf about4 Sv. The core of the jet lay between the 8.6 and9 .4 m²/s² contours of geopotential anomaly (relative to 500 dbar). Three current meter moorings, deployed at 25-km separation across the jet at the beginning of the survey sequence, provided time-series of the velocity; throughout the 37-day deployment, at least one mooring was within the core defined by the 8.6 and9 .4 m²/s² contours. The jet flowed southwestward across the grid from late June until mid-July 1988, when the jet axis moved offshore in the north and onshore in the southern portion of the grid. Temperature-salinity analysis shows that jet waters can be distinguished from both the freshly upwelled coastal waters and the offshore waters. Isopycnal maps indicate alongshore advection of relatively fresh, cool water from farther north, as well as small-scale patchiness not resolved by our survey grid. The baroclinic jet observed here may be continuous with the core of the California Current off central California. The later surveys clearly showed a poleward-flowing undercurrent adjacent to the continental slope, with core velocities up to 20 cm/s at depths of 150-250 m. Its baroclinic transport (relative to 500 dbar) increased from <0.5 Sv to >1.0 Sv between late June and early August 1988. Within the survey grid, there was a definite onshore gradient in the characteristics of North Pacific Intermediate Water. The subsurface waters adjacent to the continental margin were warmer and more saline than those offshore, indicating net northward advection by the California Undercurrent over the inshore 100 km and equatorward advection farther from shore. Title: Currents and water masses of the coastal transition zone off Northern California, June to August 1988 Author: Ramp, Steven R., Washburn, Libe, Cowles, Timothy J., Fleischbein, Jane, Stanton, Tim, Huyer, Adriana, 1945-, Kosro, P. Michael, 1951-, Smith, Robert L. (Robert Lloyd), 1935-, Pierce, Stephen D., Chavez, Francisco P. In summer 1988, we made repeated mesoscale surveys of a grid extending 200 km offshore between 37°N and 39°N in the coastal transition zone off northern California, obtaining continuous acoustic Doppler current profiler data and conductivity-temperature-depth data at standard stations 25 km apart on alongshore sections 40 km apart. All surveys showed a baroclinic equatorward jet, with core velocities of >50 cm/s at the surface decreasing to about 10 cm/s at 200m , a width of 50-75 km, and a baroclinic transporotf about4 Sv. The core of the jet lay between the 8.6 and9 .4 m²/s² contours of geopotential anomaly (relative to 500 dbar). Three current meter moorings, deployed at 25-km separation across the jet at the beginning of the survey sequence, provided time-series of the velocity; throughout the 37-day deployment, at least one mooring was within the core defined by the 8.6 and9 .4 m²/s² contours. The jet flowed southwestward across the grid from late June until mid-July 1988, when the jet axis moved offshore in the north and onshore in the southern portion of the grid. Temperature-salinity analysis shows that jet waters can be distinguished from both the freshly upwelled coastal waters and the offshore waters. Isopycnal maps indicate alongshore advection of relatively fresh, cool water from farther north, as well as small-scale patchiness not resolved by our survey grid. The baroclinic jet observed here may be continuous with the core of the California Current off central California. The later surveys clearly showed a poleward-flowing undercurrent adjacent to the continental slope, with core velocities up to 20 cm/s at depths of 150-250 m. Its baroclinic transport (relative to 500 dbar) increased from <0.5 Sv to >1.0 Sv between late June and early August 1988. Within the survey grid, there was a definite onshore gradient in the characteristics of North Pacific Intermediate Water. The subsurface waters adjacent to the continental margin were warmer and more saline than those offshore, indicating net northward advection by the California Undercurrent over the inshore 100 km and equatorward advection farther from shore. Close

• 8. [Article] Equatorward jets and poleward undercurrents along the eastern boundary of the mid-latitude north Pacific

  We sharpen our view of an eastern boundary current region during the upwelling season through the analysis of several data sets. We focus on the mesoscale flow field off of northern California, observed ...

  Citation × Citation Citation Abstract Copy Title: Equatorward jets and poleward undercurrents along the eastern boundary of the mid-latitude north Pacific Author: Pierce, Stephen D. We sharpen our view of an eastern boundary current region during the upwelling season through the analysis of several data sets. We focus on the mesoscale flow field off of northern California, observed during the Coastal Transition Zone (CTZ) experiment of 1988. First, we estimate tidal currents in the region by least-squares harmonic analysis of both shipboard acoustic Doppler current profiler (ADCP) and moored data. The tide is predominantly M2 and varies from 1-4 cm/s across the region, consistent with previous tidal studies. Next, we use detided ADCP together with conductivity-temperature-depth data to infer absolute geostrophic velocities during each of the five surveys in July-August 1988. Referencing geostrophy with the ADCP reveals a stronger equatorward jet than previously reported; southward volume transport from 0-500 m through a 200 km onshore-offshore line is as high as 8.0 Sv, with a mean over the five surveys of 6.3 +- 1.3 Sv. The jet was about 50 km wide, with core velocities > 0.6 m/s. During a two-week period in July 1988, horizontal velocity shears were sufficient to shift the effective local inertial frequency 10% higher on the cold (inshore) side and 5% lower on the warm (offshore) side of the jet. Observed near-inertial currents have amplified energy in the region with lower effective inertial frequency, consistent with theoretical predictions. Next, the basic instability mechanism leading to a meandering CTZ jet is analyzed using a linear quasi-geostrophic model applied to observed basic state velocity profiles. The jet is subject to both barotropic and baroclinic instability processes, and meander wavelengths of 260-265 km are the fastest growing. Growth periods of 7-11 days and along-jet phase speeds of 4-8 km/d are predicted. Finally, the poleward undercurrent which was observed during the 1988 CTZ experiment is also investigated with a series of shipboard ADCP sections collected from 33-51N during July-August 1995. Subsurface poleward flow occurred in 91% of the sections, with a mean undercurrent core velocity of 17 +- 1 cm/s and transport in a 140-325 m layer of 0.9 +- 0.1 Sv. One portion of the undercurrent is continuous over a 440 km length. Title: Equatorward jets and poleward undercurrents along the eastern boundary of the mid-latitude north Pacific Author: Pierce, Stephen D. We sharpen our view of an eastern boundary current region during the upwelling season through the analysis of several data sets. We focus on the mesoscale flow field off of northern California, observed during the Coastal Transition Zone (CTZ) experiment of 1988. First, we estimate tidal currents in the region by least-squares harmonic analysis of both shipboard acoustic Doppler current profiler (ADCP) and moored data. The tide is predominantly M2 and varies from 1-4 cm/s across the region, consistent with previous tidal studies. Next, we use detided ADCP together with conductivity-temperature-depth data to infer absolute geostrophic velocities during each of the five surveys in July-August 1988. Referencing geostrophy with the ADCP reveals a stronger equatorward jet than previously reported; southward volume transport from 0-500 m through a 200 km onshore-offshore line is as high as 8.0 Sv, with a mean over the five surveys of 6.3 +- 1.3 Sv. The jet was about 50 km wide, with core velocities > 0.6 m/s. During a two-week period in July 1988, horizontal velocity shears were sufficient to shift the effective local inertial frequency 10% higher on the cold (inshore) side and 5% lower on the warm (offshore) side of the jet. Observed near-inertial currents have amplified energy in the region with lower effective inertial frequency, consistent with theoretical predictions. Next, the basic instability mechanism leading to a meandering CTZ jet is analyzed using a linear quasi-geostrophic model applied to observed basic state velocity profiles. The jet is subject to both barotropic and baroclinic instability processes, and meander wavelengths of 260-265 km are the fastest growing. Growth periods of 7-11 days and along-jet phase speeds of 4-8 km/d are predicted. Finally, the poleward undercurrent which was observed during the 1988 CTZ experiment is also investigated with a series of shipboard ADCP sections collected from 33-51N during July-August 1995. Subsurface poleward flow occurred in 91% of the sections, with a mean undercurrent core velocity of 17 +- 1 cm/s and transport in a 140-325 m layer of 0.9 +- 0.1 Sv. One portion of the undercurrent is continuous over a 440 km length. Close