{"id":{"repo_id":"mit","oai_identifier":"oai:dspace.mit.edu:1721.1/59740"},"canonical_url":"https://search.dev.ndltd.org/etd/mit/oai:dspace.mit.edu:1721.1/59740","repository":{"repo_id":"mit","name":"MIT","base_url":"https://dspace.mit.edu/oai/request"},"display":{"title":"Linear and nonlinear stratified spindown over sloping topography","abstract":"In a stratified rotating fluid, frictionally driven circulations couple with the buoyancy field over sloping topography. Analytical and numerical methods are used to quantify the impact of this coupling on the vertical circulation, spindown of geostrophic flows, and the formation of a shelfbreak jet. Over a stratified. slope, linear spindown of a geostrophic along-isobath flow induces cross-isobath Ekman flows. Ekman advection of buoyancy weakens the vertical circulation and slows spindown. Upslope (downslope) Ekman flows tend to inject (remove) potential vorticity into (from) the ocean. Momentum advection and nonlinear buoyancy advection are examined in setting asymmetries in the vertical circulation and the vertical relative vorticity field. During nonlinear homogeneous spindown over a flat bottom, momentum advection weakens Ekman pumping and strengthens Ekman suction, while cyclonic vorticity decays faster than anticyclonic vorticity. During nonlinear stratified spindown over a slope, nonlinear advection of buoyancy enhances the asymmetry in Ekman pumping and suction, whereas anticyclonic vorticity can decay faster than cyclonic vorticity outside of the boundary layers. During the adjustment of a spatially uniform geostrophic current over a shelfbreak, coupling between the Ekman flow and the buoyancy field generates Ekman pumping near the shelfbreak, which leads to the formation of a jet. Scalings are presented for the upwelling strength, the length scale over which it occurs, and the timescale for jet formation. The results are applied to the Middle Atlantic Bight shelfbreak.","abstract_html":"In a stratified rotating fluid, frictionally driven circulations couple with the buoyancy field over sloping topography. Analytical and numerical methods are used to quantify the impact of this coupling on the vertical circulation, spindown of geostrophic flows, and the formation of a shelfbreak jet. Over a stratified. slope, linear spindown of a geostrophic along-isobath flow induces cross-isobath Ekman flows. Ekman advection of buoyancy weakens the vertical circulation and slows spindown. Upslope (downslope) Ekman flows tend to inject (remove) potential vorticity into (from) the ocean. Momentum advection and nonlinear buoyancy advection are examined in setting asymmetries in the vertical circulation and the vertical relative vorticity field. During nonlinear homogeneous spindown over a flat bottom, momentum advection weakens Ekman pumping and strengthens Ekman suction, while cyclonic vorticity decays faster than anticyclonic vorticity. During nonlinear stratified spindown over a slope, nonlinear advection of buoyancy enhances the asymmetry in Ekman pumping and suction, whereas anticyclonic vorticity can decay faster than cyclonic vorticity outside of the boundary layers. During the adjustment of a spatially uniform geostrophic current over a shelfbreak, coupling between the Ekman flow and the buoyancy field generates Ekman pumping near the shelfbreak, which leads to the formation of a jet. Scalings are presented for the upwelling strength, the length scale over which it occurs, and the timescale for jet formation. The results are applied to the Middle Atlantic Bight shelfbreak.","abstract_has_math":false,"creators":["Benthuysen, Jessica A"],"institution":"Massachusetts Institute of Technology","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":"Joint Program in Oceanography/Applied Ocean Science and Engineering","school":null,"contributors":[],"advisors":["Steven J. Lentz and Leif N. Thomas."],"committee_chairs":[],"committee_members":[],"year":2010,"date_issued":"2010","date_published":"2010","updated_at":"2026-07-22T22:21:44Z","subjects":["Joint Program in Oceanography/Applied Ocean Science and Engineering.","Earth, Atmospheric, and Planetary Sciences.","Woods Hole Oceanographic Institution."],"languages":["eng"],"rights":["M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission."],"rights_urls":["http://dspace.mit.edu/handle/1721.1/7582"],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/1721.1/59740","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Steven J. Lentz and Leif N. Thomas."]},{"key":"dc:contributor.department","label":"Department","values":["Joint Program in Oceanography/Applied Ocean Science and Engineering","Woods Hole Oceanographic Institution","Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences"]},{"key":"dc:contributor.other","label":"Dc Contributor Other","values":["Woods Hole Oceanographic Institution."]},{"key":"dc:creator","label":"Author","values":["Benthuysen, Jessica A"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2010-10-29T18:28:18Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2010-10-29T18:28:18Z"]},{"key":"dc:date.issued","label":"Date","values":["2010"]},{"key":"dc:publisher","label":"Institution","values":["Massachusetts Institute of Technology"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Joint Program in Oceanography/Applied Ocean Science and Engineering.","Earth, Atmospheric, and Planetary Sciences.","Woods Hole Oceanographic Institution."]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission."]},{"key":"dc:rights.uri","label":"Rights URI","values":["http://dspace.mit.edu/handle/1721.1/7582"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/1721.1/59740"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Thesis (Ph. D.)--Joint Program in Oceanography/Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences; and the Woods Hole Oceanographic Institution), 2010.","Cataloged from PDF version of thesis.","Includes bibliographical references (p. 199-205)."]},{"key":"dc:description.abstract","label":"Abstract","values":["In a stratified rotating fluid, frictionally driven circulations couple with the buoyancy field over sloping topography. Analytical and numerical methods are used to quantify the impact of this coupling on the vertical circulation, spindown of geostrophic flows, and the formation of a shelfbreak jet. Over a stratified. slope, linear spindown of a geostrophic along-isobath flow induces cross-isobath Ekman flows. Ekman advection of buoyancy weakens the vertical circulation and slows spindown. Upslope (downslope) Ekman flows tend to inject (remove) potential vorticity into (from) the ocean. Momentum advection and nonlinear buoyancy advection are examined in setting asymmetries in the vertical circulation and the vertical relative vorticity field. During nonlinear homogeneous spindown over a flat bottom, momentum advection weakens Ekman pumping and strengthens Ekman suction, while cyclonic vorticity decays faster than anticyclonic vorticity. During nonlinear stratified spindown over a slope, nonlinear advection of buoyancy enhances the asymmetry in Ekman pumping and suction, whereas anticyclonic vorticity can decay faster than cyclonic vorticity outside of the boundary layers. During the adjustment of a spatially uniform geostrophic current over a shelfbreak, coupling between the Ekman flow and the buoyancy field generates Ekman pumping near the shelfbreak, which leads to the formation of a jet. Scalings are presented for the upwelling strength, the length scale over which it occurs, and the timescale for jet formation. The results are applied to the Middle Atlantic Bight shelfbreak."]},{"key":"dc:description.degree","label":"Dc Description Degree","values":["Ph.D."]},{"key":"dc:title","label":"Title","values":["Linear and nonlinear stratified spindown over sloping topography"]}]}],"canonical_facts":{"dc:contributor.advisor":["Steven J. Lentz and Leif N. Thomas."],"dc:contributor.department":["Joint Program in Oceanography/Applied Ocean Science and Engineering","Woods Hole Oceanographic Institution","Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences"],"dc:contributor.other":["Woods Hole Oceanographic Institution."],"dc:creator":["Benthuysen, Jessica A"],"dc:date.accessioned":["2010-10-29T18:28:18Z"],"dc:date.available":["2010-10-29T18:28:18Z"],"dc:date.issued":["2010"],"dc:description":["Thesis (Ph. D.)--Joint Program in Oceanography/Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences; and the Woods Hole Oceanographic Institution), 2010.","Cataloged from PDF version of thesis.","Includes bibliographical references (p. 199-205)."],"dc:description.abstract":["In a stratified rotating fluid, frictionally driven circulations couple with the buoyancy field over sloping topography. Analytical and numerical methods are used to quantify the impact of this coupling on the vertical circulation, spindown of geostrophic flows, and the formation of a shelfbreak jet. Over a stratified. slope, linear spindown of a geostrophic along-isobath flow induces cross-isobath Ekman flows. Ekman advection of buoyancy weakens the vertical circulation and slows spindown. Upslope (downslope) Ekman flows tend to inject (remove) potential vorticity into (from) the ocean. Momentum advection and nonlinear buoyancy advection are examined in setting asymmetries in the vertical circulation and the vertical relative vorticity field. During nonlinear homogeneous spindown over a flat bottom, momentum advection weakens Ekman pumping and strengthens Ekman suction, while cyclonic vorticity decays faster than anticyclonic vorticity. During nonlinear stratified spindown over a slope, nonlinear advection of buoyancy enhances the asymmetry in Ekman pumping and suction, whereas anticyclonic vorticity can decay faster than cyclonic vorticity outside of the boundary layers. During the adjustment of a spatially uniform geostrophic current over a shelfbreak, coupling between the Ekman flow and the buoyancy field generates Ekman pumping near the shelfbreak, which leads to the formation of a jet. Scalings are presented for the upwelling strength, the length scale over which it occurs, and the timescale for jet formation. The results are applied to the Middle Atlantic Bight shelfbreak."],"dc:description.degree":["Ph.D."],"dc:identifier.uri":["http://hdl.handle.net/1721.1/59740"],"dc:language.iso":["eng"],"dc:publisher":["Massachusetts Institute of Technology"],"dc:rights":["M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission."],"dc:rights.uri":["http://dspace.mit.edu/handle/1721.1/7582"],"dc:subject":["Joint Program in Oceanography/Applied Ocean Science and Engineering.","Earth, Atmospheric, and Planetary Sciences.","Woods Hole Oceanographic Institution."],"dc:title":["Linear and nonlinear stratified spindown over sloping topography"],"dc:type":["Thesis"]},"updated_at":"2026-07-22T22:21:44Z"}