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• 1. [Article] Bottom boundary layer flow and salt injection from the continental shelf to slope

  Austral winter oceanographic measurements from the northwest Australian continental shelf reveal salty water forming evaporatively inshore, moving across the wide shelf near the bottom and into the adjacent ...

  Citation × Citation Citation Abstract Copy Title: Bottom boundary layer flow and salt injection from the continental shelf to slope Author: Shearman, R. Kipp, Brink, K.H. Austral winter oceanographic measurements from the northwest Australian continental shelf reveal salty water forming evaporatively inshore, moving across the wide shelf near the bottom and into the adjacent open ocean when the shelf edge alongshore flow is equatorward. The salt tongue is absent during more normal conditions, when the poleward Leeuwin Current is present. We hypothesize that the flow reversal enables shelf-wide bottom boundary layer (Ekman) transport and thus creates the shelf-edge convergence that accounts for the observed salt tongue. This flow is absent under sustained normal conditions because of buoyancy arrest in the bottom boundary layer. Title: Bottom boundary layer flow and salt injection from the continental shelf to slope Author: Shearman, R. Kipp, Brink, K.H. Austral winter oceanographic measurements from the northwest Australian continental shelf reveal salty water forming evaporatively inshore, moving across the wide shelf near the bottom and into the adjacent open ocean when the shelf edge alongshore flow is equatorward. The salt tongue is absent during more normal conditions, when the poleward Leeuwin Current is present. We hypothesize that the flow reversal enables shelf-wide bottom boundary layer (Ekman) transport and thus creates the shelf-edge convergence that accounts for the observed salt tongue. This flow is absent under sustained normal conditions because of buoyancy arrest in the bottom boundary layer. Close

• 2. [Article] Bottom boundary layer flow and salt injection from the continental shelf to slope

  Copyrighted by American Geophysical Union.

  Citation × Citation Citation Abstract Copy Title: Bottom boundary layer flow and salt injection from the continental shelf to slope Author: Shearman, R. Kipp, Brink, K. H. Copyrighted by American Geophysical Union. Title: Bottom boundary layer flow and salt injection from the continental shelf to slope Author: Shearman, R. Kipp, Brink, K. H. Copyrighted by American Geophysical Union. Close

• 3. [Article] Dynamics of mean and subtidal flow on the New England shelf

  Current and hydrographic observations from the Coastal Mixing and Optics experiment moored array, deployed from August 1996 through June 1997, are used to describe the velocity variability and evaluate ...

  Citation × Citation Citation Abstract Copy Title: Dynamics of mean and subtidal flow on the New England shelf Author: Shearman, R. Kipp, Lentz, Steven J. Current and hydrographic observations from the Coastal Mixing and Optics experiment moored array, deployed from August 1996 through June 1997, are used to describe the velocity variability and evaluate the dynamics of circulation over the New England shelf on timescales ranging from a few days to several months. Subtidal (days to weeks) current variability was polarized along-isobath and dominated by episodic bursts of westward flow. The along-isobath subtidal flow was primarily geostrophic and barotropic, and was correlated with large-scale along-coast wind stress fluctuations oriented 45°T (65° counterclockwise from the local isobath orientation). Subtidal nearsurface ageostrophic transport matched estimates of wind-driven Ekman transport; however, near-bottom ageostrophic transport was much larger than estimates of Ekman transport from bottom stress. Low-frequency (monthly and longer timescales) flow was generally westward and off-shelf at all sites and depths, with the strongest westward flow during the fall. Low-frequency along-isobath currents were primarily geostrophic with baroclinic and barotropic components of similar magnitude. Depth-averaged ageostrophic transport was quantitatively consistent with Ekman transport from wind and bottom stress. Measured bottom stress at both subtidal and low-frequency timescales was weak, nearly an order of magnitude smaller than the wind stress. Low-frequency fluctuations in the predominantly geostrophic along-isobath flow were attributable to variations in the cross-shelf density field associated with the seasonal cycle in surface heating. During the fall, thermal wind shear was strongest, because the cross-isobath temperature gradient was acting in concert with the persistent cross-isobath salinity gradient to enhance the cross-isobath density gradient (i.e., warmer and fresher water inshore). During the winter, in response to surface cooling, the cross-isobath temperature gradient reversed sign, reducing the cross-isobath density gradient (i.e., cooler and fresher water inshore). Title: Dynamics of mean and subtidal flow on the New England shelf Author: Shearman, R. Kipp, Lentz, Steven J. Current and hydrographic observations from the Coastal Mixing and Optics experiment moored array, deployed from August 1996 through June 1997, are used to describe the velocity variability and evaluate the dynamics of circulation over the New England shelf on timescales ranging from a few days to several months. Subtidal (days to weeks) current variability was polarized along-isobath and dominated by episodic bursts of westward flow. The along-isobath subtidal flow was primarily geostrophic and barotropic, and was correlated with large-scale along-coast wind stress fluctuations oriented 45°T (65° counterclockwise from the local isobath orientation). Subtidal nearsurface ageostrophic transport matched estimates of wind-driven Ekman transport; however, near-bottom ageostrophic transport was much larger than estimates of Ekman transport from bottom stress. Low-frequency (monthly and longer timescales) flow was generally westward and off-shelf at all sites and depths, with the strongest westward flow during the fall. Low-frequency along-isobath currents were primarily geostrophic with baroclinic and barotropic components of similar magnitude. Depth-averaged ageostrophic transport was quantitatively consistent with Ekman transport from wind and bottom stress. Measured bottom stress at both subtidal and low-frequency timescales was weak, nearly an order of magnitude smaller than the wind stress. Low-frequency fluctuations in the predominantly geostrophic along-isobath flow were attributable to variations in the cross-shelf density field associated with the seasonal cycle in surface heating. During the fall, thermal wind shear was strongest, because the cross-isobath temperature gradient was acting in concert with the persistent cross-isobath salinity gradient to enhance the cross-isobath density gradient (i.e., warmer and fresher water inshore). During the winter, in response to surface cooling, the cross-isobath temperature gradient reversed sign, reducing the cross-isobath density gradient (i.e., cooler and fresher water inshore). Close

• 4. [Article] Dynamics of mean and subtidal flow on the New England shelf

  Copyrighted by American Geophysical Union.

  Citation × Citation Citation Abstract Copy Title: Dynamics of mean and subtidal flow on the New England shelf Author: Shearman, R. Kipp, Lentz, Steven J. Copyrighted by American Geophysical Union. Title: Dynamics of mean and subtidal flow on the New England shelf Author: Shearman, R. Kipp, Lentz, Steven J. Copyrighted by American Geophysical Union. Close

• 5. [Article] Alongshore currents and mesoscale variability near the shelf edge off northwestern Australia

  Copyrighted by American Geophysical Union.

  Citation × Citation Citation Abstract Copy Title: Alongshore currents and mesoscale variability near the shelf edge off northwestern Australia Author: Shearman, R. Kipp, Brink, K. H., Bahr, Frank Copyrighted by American Geophysical Union. Title: Alongshore currents and mesoscale variability near the shelf edge off northwestern Australia Author: Shearman, R. Kipp, Brink, K. H., Bahr, Frank Copyrighted by American Geophysical Union. Close

• 6. [Article] Alongshore currents and mesoscale variability near the shelf edge off northwestern Australia

  Shelf break conditions and alongshore flow off northwestern Australia are studied during the strongly evaporative conditions of austral winter 2003. Present results, along with those of previous authors, ...

  Citation × Citation Citation Abstract Copy Title: Alongshore currents and mesoscale variability near the shelf edge off northwestern Australia Author: Bahr, Frank, Shearman, R. Kipp, Brink, K.H. Shelf break conditions and alongshore flow off northwestern Australia are studied during the strongly evaporative conditions of austral winter 2003. Present results, along with those of previous authors, confirm that a poleward, fresh Leeuwin current core is normally found near the shelf break. Salinity increases alongshore toward the southwest. Although there is no obvious shelf break front, there is a persistent offshore upward tilting of isopycnals in the depth range of 100–150 m. Repeated mesoscale surveys were made at the shelf edge during 8 days when the shelf break flow was equatorward. Waters offshore of the shelf break contain a rich baroclinic ageostrophic eddy field, with typically 10 km length scales, and the eddy patterns in the upper 60 m are uncorrelated with those below 90 m. The two depth horizons yield energy transfers from mean to eddy potential energy and appear to represent distinct finite amplitude instabilities on upper ocean and 180 m mean velocity cores, respectively. A linear stability model supports the existence of the two vertically separated instability types. Title: Alongshore currents and mesoscale variability near the shelf edge off northwestern Australia Author: Bahr, Frank, Shearman, R. Kipp, Brink, K.H. Shelf break conditions and alongshore flow off northwestern Australia are studied during the strongly evaporative conditions of austral winter 2003. Present results, along with those of previous authors, confirm that a poleward, fresh Leeuwin current core is normally found near the shelf break. Salinity increases alongshore toward the southwest. Although there is no obvious shelf break front, there is a persistent offshore upward tilting of isopycnals in the depth range of 100–150 m. Repeated mesoscale surveys were made at the shelf edge during 8 days when the shelf break flow was equatorward. Waters offshore of the shelf break contain a rich baroclinic ageostrophic eddy field, with typically 10 km length scales, and the eddy patterns in the upper 60 m are uncorrelated with those below 90 m. The two depth horizons yield energy transfers from mean to eddy potential energy and appear to represent distinct finite amplitude instabilities on upper ocean and 180 m mean velocity cores, respectively. A linear stability model supports the existence of the two vertically separated instability types. Close

• 7. [Article] Evaporative dense water formation and cross‐shelf exchange over the northwest Australian inner shelf

  High‐resolution surveys of oceanographic and atmospheric conditions made during the winter over the inner shelf off northwest Australia are used to examine the coastal ocean response to large outgoing ...

  Citation × Citation Citation Abstract Copy Title: Evaporative dense water formation and cross‐shelf exchange over the northwest Australian inner shelf Author: Shearman, R. Kipp, Brink, Kenneth H. High‐resolution surveys of oceanographic and atmospheric conditions made during the winter over the inner shelf off northwest Australia are used to examine the coastal ocean response to large outgoing heat and freshwater fluxes. Relatively cool, low‐humidity air blows off the Australian continent out over the tropical continental shelf, resulting in a large mean latent heat flux (−177Wm−2) that overwhelms insolation and, along with the outgoing long‐wave radiation, results in substantial net cooling (−105 W m−2) and evaporative freshwater flux (0.6 cm d−1). The inner shelf is characterized by increasingly cool, salty, and dense waters onshore, with a strong front near the 25 m isobath. The front is evident in satellite sea surface temperature (SST) imagery along the majority of the northwest Australian shelf, exhibiting a complex filamentary and eddy structure. Cross‐shelf buoyancy fluxes estimated from the mean, two‐dimensional heat and salt budgets are comparable to parameterizations of cross‐shelf eddy driven fluxes; however, the same fluxes can be achieved by cross‐shelf transports in the bottom boundary layer of about 0.5 m2 s−1 (and an overlying return flow). Title: Evaporative dense water formation and cross‐shelf exchange over the northwest Australian inner shelf Author: Shearman, R. Kipp, Brink, Kenneth H. High‐resolution surveys of oceanographic and atmospheric conditions made during the winter over the inner shelf off northwest Australia are used to examine the coastal ocean response to large outgoing heat and freshwater fluxes. Relatively cool, low‐humidity air blows off the Australian continent out over the tropical continental shelf, resulting in a large mean latent heat flux (−177Wm−2) that overwhelms insolation and, along with the outgoing long‐wave radiation, results in substantial net cooling (−105 W m−2) and evaporative freshwater flux (0.6 cm d−1). The inner shelf is characterized by increasingly cool, salty, and dense waters onshore, with a strong front near the 25 m isobath. The front is evident in satellite sea surface temperature (SST) imagery along the majority of the northwest Australian shelf, exhibiting a complex filamentary and eddy structure. Cross‐shelf buoyancy fluxes estimated from the mean, two‐dimensional heat and salt budgets are comparable to parameterizations of cross‐shelf eddy driven fluxes; however, the same fluxes can be achieved by cross‐shelf transports in the bottom boundary layer of about 0.5 m2 s−1 (and an overlying return flow). Close

• 8. [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

• 9. [Article] The LatMix Summer Campaign: Submesoscale Stirring in the Upper Ocean

  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 the American ...

  Citation × Citation Citation Abstract Copy Title: The LatMix Summer Campaign: Submesoscale Stirring in the Upper Ocean Author: Shearman, R. Kipp, Kunze, Eric, Levine, Murray D., Shcherbina, Andrey Y., Cervantes, Brandy T. Kuebel, Skyllingstad, Eric D, Pierce, Stephen D., Samelson, Roger M., Sundermeyer, Miles A., Nash, Jonathan D., et al. 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 the American Meteorological Society and can be found at: https://www2.ametsoc.org/ams/index.cfm/publications/bulletin-of-the-american-meteorological-society-bams/ Title: The LatMix Summer Campaign: Submesoscale Stirring in the Upper Ocean Author: Shearman, R. Kipp, Kunze, Eric, Levine, Murray D., Shcherbina, Andrey Y., Cervantes, Brandy T. Kuebel, Skyllingstad, Eric D, Pierce, Stephen D., Samelson, Roger M., Sundermeyer, Miles A., Nash, Jonathan D., et al. 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 the American Meteorological Society and can be found at: https://www2.ametsoc.org/ams/index.cfm/publications/bulletin-of-the-american-meteorological-society-bams/ Close