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dc.contributor.authorKlenz, Thilo
dc.date.accessioned2023-08-21T00:25:58Z
dc.date.available2023-08-21T00:25:58Z
dc.date.issued2023-05
dc.identifier.urihttp://hdl.handle.net/11122/13240
dc.descriptionDissertation (PH.D.) University of Alaska Fairbanks, 2023en_US
dc.description.abstractLagrangian surface drifters are powerful tools to study the dynamics of the ocean across a variety of spatial and temporal scales, ranging from regional to global and monthly to climatological, respectively. This dissertation investigates the utility of Lagrangian surface drifters for estimating the mechanical input of energy into the ocean by the atmosphere, and for gathering information about the underlying dynamics driving oceanic variability. The basis for the analysis was a large dataset of 88 surface drifters deployed in the subpolar North Atlantic between 2018 and 2019. In addition, numerical drifters from both idealized and realistic ocean models were used to supplement the observations. The study region is characterized by pronounced mesoscale eddy activity and, due to its proximity to the North Atlantic storm track, strong atmospheric storms causing energetic near-inertial oscillations. It is hence well-suited for the analyses presented here. We introduced a novel surface drifter instrument, the Minimet, that measures sea surface wind in situ along the drifter track. Estimates of in situ Minimet wind power input were found to be over 40% higher than those using a reanalysis wind product. This discrepancy was likely due to Minimets accurately capturing strong high-frequency wind events that were misrepresented in the reanalysis product, highlighting the utility of the Minimets for both wind power input calculations and the important validation of gridded wind products. We currently lack a basic understanding of the Lagrangian velocity frequency spectrum and how it relates to the underlying dynamics. We therefore investigated the Lagrangian spectral shape and found significant variability linked to eddy kinetic energy. Lastly, we established a direct link between the Lagrangian velocity frequency spectrum and Eulerian kinetic energy wavenumber spectrum. This link had not previously been made from single particles and together with a better understanding of the Lagrangian frequency spectrum furthers our ability to efficiently utilize Lagrangian data.en_US
dc.description.sponsorshipNational Science Foundation (Grant 1658302) and the Office of Naval Research (Grant N000141812386)en_US
dc.description.tableofcontentsGeneral introduction -- Chapter 1: Estimates of near-inertial wind power input using novel in situ wind measurements from Minimet surface drifters in the Iceland basin -- Chapter 2: A general description of the Lagrangian frequency spectral shape in relation to environmental parameters -- Chapter 3: Establishing a link between the Lagrangian frequency spectrum and the Eulerian wavenumber spectrum from single-particle metrics -- General conclusion -- References.en_US
dc.language.isoen_USen_US
dc.subjectOcean wave poweren_US
dc.subjectNorth Atlantic Oceanen_US
dc.subjectIceland Basinen_US
dc.subjectOcean wavesen_US
dc.subjectOcean currentsen_US
dc.subjectLagrangian pointsen_US
dc.subject.otherDoctor of Philosophy in Oceanographyen_US
dc.titleLagrangian surface drifter analyses from observations and numerical modeling in the subpolar North Atlanticen_US
dc.typeDissertationen_US
dc.type.degreephden_US
dc.identifier.departmentDepartment of Oceanographyen_US
dc.contributor.chairSimmons, Harper L.
dc.contributor.committeeLilly, Jonathan M.
dc.contributor.committeeDanielson, Seth
dc.contributor.committeeJohnson, Mark A.
dc.contributor.committeeHennon, Gwenn


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