Pushing Back Against Deficit Narratives: Mentoring as Scholars of Color

In this article we share our lived experiences with mentoring. As tenured women professors of color, we push back against the assumption that institutions of higher education are neutral sites, that we have to change to belong, and that we do not belong. Each of us underscores the importance and value of our realities and the knowledge we generate to address inequality and to counteract negative stereotyping. We argue that rejecting deficit narratives and privileging the narratives of those we mentor and of those who have mentored us is vital to increasing faculty of color diversity, inclusion and belonging in higher education.Educatio

Eddy-mean flow interactions in western boundary current jets

Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution February 2009.This thesis examines the nature of eddy-mean flow interactions in western boundary current jets and recirculation gyre dynamics from both theoretical and observational perspectives. It includes theoretical studies of eddy-mean flow interactions in idealized configurations relevant to western boundary current jet systems, namely (i) a study of the mechanism by which eddies generated from a localized forcing drive mean recirculation gyres through the process of nonlinear rectification; and (ii) a study of the role of eddies in the downstream evolution of a baroclinic jet subject to mixed instabilities. It also includes an observational analysis to characterize eddy-mean flow interactions in the Kuroshio Extension using data from the downstream location of maximum eddy kinetic energy in the jet. New insights are presented into a rectification mechanism by which eddies drive the recirculation gyres observed in western boundary current systems. Via this mechanism, eddies drive the recirculations by an up-gradient eddy potential vorticity flux inside a localized region of eddy activity. The effectiveness of the process depends on the properties of the energy radiation from the region, which in turn depends on the population of waves excited. In the zonally-evolving western boundary current jet, eddies also act to stabilize the unstable jet through down-gradient potential vorticity fluxes. In this configuration, the role of eddies depends critically on their downstream location relative to where the unstable time-mean jet first becomes stabilized by the eddy activity. The zonal advection of eddy activity from upstream of this location is fundamental to the mechanism permitting the eddies to drive the mean flows. Observational results are presented that provide the first clear evidence of a northern recirculation gyre in the Kuroshio Extension, as well as support for the hypothesis that the recirculations are, at least partially, eddy-driven. Support for the idealized studies’ relevance to the oceanic regime is provided both by indications that various model simplifications are appropriate to the observed system, as well as by demonstrated consistencies between model predictions and observational results in the downstream development of time-mean and eddy properties.Funding was for this research and my education was provided by the MIT Presidential Fellowship and NSF grants OCE-0220161 and OCE-0825550. The financial assistance of the Houghton Fund, the MIT Student Assistance Fund, and WHOI Academic Programs is also gratefully acknowledged

Jet-Topography Interactions Affect Energy Pathways to the Deep Southern Ocean

In the Southern Ocean, strong eastward ocean jets interact with large topographic features, generating eddies that feed back onto the mean flow. Deep-reaching eddies interact with topography, where turbulent dissipation and generation of internal lee waves play an important role in the ocean's energy budget. However, eddy effects in the deep ocean are difficult to observe and poorly characterized. This study investigates the energy contained in eddies at depth, when an ocean jet encounters topography. This study uses a two-layer ocean model in which an imposed unstable jet encounters a topographic obstacle (either a seamount or a meridional ridge) in a configuration relevant to an Antarctic Circumpolar Current frontal jet. The authors find that the presence of topography increases the eddy kinetic energy (EKE) at depth but that the dominant processes generating this deep EKE depend on the shape and height of the obstacle as well as on the baroclinicity of the jet before it encounters topography. In cases with high topography, horizontal shear instability is the dominant source of deep EKE, while a flat bottom or a strongly sheared inflow leads to deep EKE being generated primarily through baroclinic instability. These results suggest that the deep EKE is set by an interplay between the inflowing jet properties and topography and imply that the response of deep EKE to changes in the Southern Ocean circulation is likely to vary across locations depending on the topography characteristics

Eddy shape, orientation, propagation and mean flow feedback in western boundary current jets

This manuscript revisits a study of eddy-mean flow interactions in an idealized model of a western boundary current extension jet using properties of the horizontal velocity correlation tensor to diagnose characteristics of average eddy shape, orientation, propagation, and mean flow feedback. These eddy characteristics are then used to provide a new description of the eddy-mean flow interactions observed in terms of different ingredients of the eddy motion. The diagnostics show patterns in average eddy shape, orientation, and propagation that are consistent with the signatures of jet instability in the upstream region and wave radiation in the downstream region. Together they give a feedback onto the mean flow that gives the downstream character of the jet and drives the jet's recirculation gyres. A breakdown of the eddy forcing into contributions from individual terms confirms the expected role of cross-jet gradients in meridional eddy tilt in stabilizing the jet to its barotropic instability; however, it also reveals important roles played by the along-jet evolution of eddy zonal-meridional elongation. It is the mean flow forcing derived from these patterns that acts to strengthen and extend the jet downstream and forces the time-mean recirculation gyres. This understanding of the dependence of mean flow forcing on eddy structural properties suggests that failure to adequately resolve eddy elongation could underlie the weakened jet strength, extent, and changed recirculation structure seen in this idealized model for reduced spatial resolutions. Further, it may suggest new ideas for the parameterization of this forcing

Native American College Students: A Group Forgotten

Broadening McClellan’s (2003) study through 2011, the authors utilize qualitative content analysis of over two thousand journal articles, professional association conference programs, and reflective memos, to detail the extent to which Native American college students remain a forgotten group within the literature. The authors’ positionality and Indigenous feminist theory inform the study. The study concludes by exploring the benefits of expanded Native American college student research and the authors propose a research agenda that can guide higher education professionals to better serve the educational needs of this unique group

Antarctic circumpolar current impacts on internal wave life cycles

Author Posting. © American Geophysical Union, 2021. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geophysical Research Letters 48(8), (2021): e2020GL089471, https://doi.org/10.1029/2020GL089471.Major gaps exist in our understanding of the pathways between internal wave generation and breaking in the Southern Ocean, with important implications for the distribution of internal wave-driven mixing, the sensitivity of ocean mixing rates and patterns to changes in the ocean environment, and the necessary ingredients of mixing parameterizations. Here we assess the dominant processes in internal wave evolution by characterizing wave and mesoscale flow scales based on full-depth in situ measurements in a Southern Ocean mixing hot spot and a ray tracing calculation. The exercise highlights the importance of Antarctic Circumpolar Current jets as a dominant influence on internal wave life cycles through advection, the modification of wave characteristics via wave-mean flow interactions, and the set-up of critical layers for both upward- and downward-propagating waves. Our findings suggest that it is important to represent mesoscale flow impacts in parameterizations of internal wave-driven mixing in the Southern Ocean.The SOFine project was funded by the UK Natural Environmental Research Council (NERC) (grant NE/G001510/1). S. Waterman is currently supported by the National Science and Engineering Research Council of Canada (NSERC) Discovery Grant Program (NSERC-2020-05799). A. Meyer acknowledges current support from the ARC Centre of Excellence for Climate Extremes (CE170100023) and previous support from the joint CSIRO-University of Tasmania Quantitative Marine Science (QMS) program. A. N. Garabato acknowledges the support of the Royal Society and the Wolfson Foundation

Preventing Teen Relationship Abuse and Sexual Assault through Bystander Training: Intervention Outcomes for School Personnel

The purpose of the current study was to examine the impact of exposure to Bringing in the Bystander—High School Curriculum (BITB-HSC) on school personnel, which included a seven session classroom curriculum for ninth through twelfth graders (student curriculum), a bystander training workshop for school personnel (school personnel workshop), and reading materials (handout). We examined how exposure to these various BITB-HSC intervention components was associated with school personnel’s knowledge and bystander efficacy, intentions, and barriers specific to student relationship abuse (RA) and sexual assault (SA). Participants were 488 school personnel from 12 high schools in upper New England who completed the 4-month follow-up survey that assessed for intervention exposure (284 participants completed both the baseline and follow-up survey). Whereas 53% of participants were exposed to no intervention components, the other half of the sample were exposed to a combination of intervention components. Higher baseline knowledge and reactive bystander intentions were associated with subsequent exposure to both the student curriculum and the handout, and fewer barriers to bystander action predicted exposure to the school personnel workshop. Exposure to the school personnel workshop, student curriculum, and handout was associated with subsequent greater knowledge, exposure to the student curriculum predicted reactive bystander intentions, and exposure to the handout predicted higher reactive bystander intentions and bystander efficacy. Findings suggest that despite challenges with engagement, exposure to the BITB-HSC components may be a useful tool in improving school personnel’s responses to RA and SA among high school students

Internal lee wave closures : parameter sensitivity and comparison to observations

Author Posting. © American Geophysical Union, 2015. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Oceans 120 (2015): 7997–8019, doi:10.1002/2015JC010892.This paper examines two internal lee wave closures that have been used together with ocean models to predict the time-averaged global energy conversion rate into lee waves and dissipation rate associated with lee waves and topographic blocking: the Garner (2005) scheme and the Bell (1975) theory. The closure predictions in two Southern Ocean regions where geostrophic flows dominate over tides are examined and compared to microstructure profiler observations of the turbulent kinetic energy dissipation rate, where the latter are assumed to reflect the dissipation associated with topographic blocking and generated lee wave energy. It is shown that when applied to these Southern Ocean regions, the two closures differ most in their treatment of topographic blocking. For several reasons, pointwise validation of the closures is not possible using existing observations, but horizontally averaged comparisons between closure predictions and observations are made. When anisotropy of the underlying topography is accounted for, the two horizontally averaged closure predictions near the seafloor are approximately equal. The dissipation associated with topographic blocking is predicted by the Garner (2005) scheme to account for the majority of the depth-integrated dissipation over the bottom 1000 m of the water column, where the horizontally averaged predictions lie well within the spatial variability of the horizontally averaged observations. Simplifications made by the Garner (2005) scheme that are inappropriate for the oceanic context, together with imperfect observational information, can partially account for the prediction-observation disagreement, particularly in the upper water column.National Science Foundation Grant Number: OCE-0960820; Office of Naval Research (ONR) Grant Number: N00014-11-1-0487; Australian Research Council Grant Number: (DE120102927 and CE110001028); National Science and Engineering Research Council of Canada Grant Number: (22R23085)2016-06-1

Global patterns of diapycnal mixing from measurements of the turbulent dissipation rate

The authors present inferences of diapycnal diffusivity from a compilation of over 5200 microstructure profiles. As microstructure observations are sparse, these are supplemented with indirect measurements of mixing obtained from (i) Thorpe-scale overturns from moored profilers, a finescale parameterization applied to (ii) shipboard observations of upper-ocean shear, (iii) strain as measured by profiling floats, and (iv) shear and strain from full-depth lowered acoustic Doppler current profilers (LADCP) and CTD profiles. Vertical profiles of the turbulent dissipation rate are bottom enhanced over rough topography and abrupt, isolated ridges. The geography of depth-integrated dissipation rate shows spatial variability related to internal wave generation, suggesting one direct energy pathway to turbulence. The global-averaged diapycnal diffusivity below 1000-m depth is O(10?4) m2 s?1 and above 1000-m depth is O(10?5) m2 s?1. The compiled microstructure observations sample a wide range of internal wave power inputs and topographic roughness, providing a dataset with which to estimate a representative global-averaged dissipation rate and diffusivity. However, there is strong regional variability in the ratio between local internal wave generation and local dissipation. In some regions, the depth-integrated dissipation rate is comparable to the estimated power input into the local internal wave field. In a few cases, more internal wave power is dissipated than locally generated, suggesting remote internal wave sources. However, at most locations the total power lost through turbulent dissipation is less than the input into the local internal wave field. This suggests dissipation elsewhere, such as continental margins