• MABEL photon-counting laser altimetry data in Alaska for ICESat-2 simulations and development

      Brunt, Kelly M.; Neumann, Thomas A.; Amundson, Jason M.; Kavanaugh, Jeffrey L.; Moussavi, Mahsa S.; Walsh, Kaitlin M.; Cook, William B.; Markus, Thorsten (Copernicus Publications on behalf of the European Geosciences Union, 2016-08-10)
      Ice, Cloud, and land Elevation Satellite-2 (ICESat-2) is scheduled to launch in late 2017 and will carry the Advanced Topographic Laser Altimeter System (ATLAS) which is a photon-counting laser altimeter and represents a new approach to satellite determination of surface elevation. Given the new technology of ATLAS, an airborne instrument, the Multiple Altimeter Beam Experimental Lidar (MABEL), was developed to provide data needed for satellite-algorithm development and ICESat-2 error analysis. MABEL was deployed out of Fairbanks, Alaska, in July 2014 to provide a test dataset for algorithm development in summer conditions with water-saturated snow and ice surfaces. Here we compare MABEL lidar data to in situ observations in Southeast Alaska to assess instrument performance in summer conditions and in the presence of glacier surface melt ponds and a wet snowpack. Results indicate the following: (1) based on MABEL and in situ data comparisons, the ATLAS 90m beam-spacing strategy will provide a valid assessment of across-track slope that is consistent with shallow slopes (< 1) of an ice-sheet interior over 50 to 150m length scales; (2) the dense along-track sampling strategy of photon counting systems can provide crevasse detail; and (3) MABEL 532 nm wavelength light may sample both the surface and subsurface of shallow (approximately 2m deep) supraglacial melt ponds. The data associated with crevasses and melt ponds indicate the potential ICESat-2 will have for the study of mountain and other small glaciers.
    • Managing Students' Emotional Behavioral Disorder Inside and Outside of the Classroom: A Meta-Synthesis

      Fielding, Estelita D. (University of Alaska Southeast, 2012-06-11)
      This metasynthesis of the literature focuses on managing students with emotional/behavioral disorders (EBD) inside and outside of the classroom. Students with EBD require large amounts of time and attention, often unplanned and in response to disruptive behaviors. Students with EBD can take a heavy emotional and physical toll on teachers, staff and peers involved with them, and instruction time for other students can be shortened or delayed due to disruptive behaviors. School districts find retention more difficult when students with EBD are present due to the high stress factor. When teachers and staff have the appropriate preparation and tools, however, students with EBD can be successful in an inclusive school setting with minimal disruptive behavior. Furthermore, as they make progress, they can practice self-management techniques to achieve more independence.
    • A mass-flux perspective of the tidewater glacier cycle

      Amundson, Jason M. (International Glaciological Society, 2016-04-06)
      I explore the tidewater glacier cycle with a 1-D, depth- and width-integrated flow model that includes a mass-flux calving parameterization. The parameterization is developed from mass continuity arguments and relates the calving rate to the terminus velocity and the terminus balance velocity. The model demonstrates variable sensitivity to climate. From an advanced, stable configuration, a small warming of the climate triggers a rapid retreat that causes large-scale drawdown and is enhanced by positive glacier-dynamic feedbacks. Eventually, the terminus retreats out of deep water and the terminus velocity decreases, resulting in reduced drawdown and the potential for restabilization. Terminus readvance can be initiated by cooling the climate. Terminus advance into deep water is difficult to sustain, however, due to negative feedbacks between glacier dynamics and surface mass balance. Despite uncertainty in the precise form of the parameterization, the model provides a simple explanation of the tidewater glacier cycle and can be used to evaluate the response of tidewater glaciers to climate variability. It also highlights the importance of improving parameterizations of calving rates and of incorporating sediment dynamics into tidewater glacier models.
    • Mathematical Modeling and Simulation with MATLAB

      Buzby, Megan; Lee, Sheldon (2021)
      This textbook attempts to provide you with an overview of the commonly used basic mathematical models, as well as a wide range of applications. It offers a perspective that brings you back to the modeling process and the assumptions that go into it.
    • Meals in the melting-pot: Immigration and dietary change in diversifying cities

      Rule, Nicola Frances; Dring, Colin Charles; Thornton, Thomas F. (Elsevier, 2021-09-30)
      Changes in diets and food practices have implications for personal and planetary health. As these implications have become more apparent, dietary change interventions that seek to promote healthy and sustainable transitions have proliferated, and the processes and drivers of dietary change have come under increasing scrutiny. In particular, dietary acculturation has been recognised as a driver of dietary change in the context of immigration to expanding, cosmopolitan cities. However, research has largely focused on changes in the diets of immigrants and ethnic minorities. In contrast, this study contributes to our understanding of the process of dietary acculturation among the largest population groups in Vancouver, Canada — Chinese- and European-Canadians — in the context of the rapid diversification of the population and food environments in this city. This is done through the analysis of descriptive and contextualised interview and observational data, and a focus on social practices. These data show that food practices, particularly in cosmopolitan urban contexts, are constantly in flux, as diverse ethnic groups come into contact, and new generations develop their own hybrid food cultures. By demonstrating and theorising this process of dietary acculturation, this research offers insights how cultural interactions relate to dietary transitions. It presents an exploratory model for considering how food practices change through dietary acculturation, which is relevant to the design of interventions that aim to support healthier and more sustainable dietary transitions.
    • Meltwater Intrusions Reveal Mechanisms for Rapid Submarine Melt at a Tidewater Glacier

      Kienholtz, C.; Sutherland, D. A.; Jackson, R. H.; Nash, J. D.; Amundson, Jason M.; Motyka, R. J.; Winters, D.; Skyllingstad, E.; Pettit, E. C. (American Geophysical Union, 2019-11-25)
      Submarine melting has been implicated as a driver of glacier retreat and sea level rise, but to date melting has been difficult to observe and quantify. As a result, melt rates have been estimated from parameterizations that are largely unconstrained by observations, particularly at the near-vertical termini of tidewater glaciers. With standard coefficients, these melt parameterizations predict that ambient melting (the melt away from subglacial discharge outlets) is negligible compared to discharge-driven melting for typical tidewater glaciers. Here, we present new data from LeConte Glacier, Alaska, that challenges this paradigm. Using autonomous kayaks, we observe ambient meltwater intrusions that are ubiquitous within 400 m of the terminus, and we provide the first characterization of their properties, structure, and distribution. Our results suggest that ambient melt rates are substantially higher (×100) than standard theory predicts and that ambient melting is a significant part of the total submarine melt flux. We explore modifications to the prevalent melt parameterization to provide a path forward for improved modeling of ocean-glacier interactions.
    • Membranes Are Decisive for Maximum Freezing Efficiency of Bacterial Ice Nucleators

      Schwidetzky, R.; Sudera, P.; Backes, A. T.; Pöschl, U.; Bonn, M.; Fröhlich-Nowoisky, J.; Meister, Konrad (American Chemical Society, 2021-11-01)
      Ice-nucleating proteins (INPs) from Pseudomonas syringae are among the most active ice nucleators known, enabling ice formation at temperatures close to the melting point of water. The working mechanisms of INPs remain elusive, but their ice nucleation activity has been proposed to depend on the ability to form large INP aggregates. Here, we provide experimental evidence that INPs alone are not sufficient to achieve maximum freezing efficiency and that intact membranes are critical. Ice nucleation measurements of phospholipids and lipopolysaccharides show that these membrane components are not part of the active nucleation site but rather enable INP assembly. Substantially improved ice nucleation by INP assemblies is observed for deuterated water, indicating stabilization of assemblies by the stronger hydrogen bonds of D2O. Together, these results show that the degree of order/disorder and the assembly size are critically important in determining the extent to which bacterial INPs can facilitate ice nucleation.
    • Message from the Chancellor: 2020-07-15

      Carey, Karen (University of Alaska Southeast, 2020-07-15)
    • Message from the Chancellor: 2020-08-10

      Carey, Karen (University of Alaska Southeast, 2020-08-10)
    • Message from the Chancellor: 2020-09-14

      Carey, Karen (University of Alaska Southeast, 2020-09-14)
    • Message from the Chancellor: 2020-11-12

      Carey, Karen (University of Alaska Southeast, 2020-11-12)
    • Message from the Chancellor: 2021-02-19

      Carey, Karen (University of Alaska Southeast, 2021-02-19)
    • Message from the Chancellor: 2021-05-03

      Carey, Karen (University of Alaska Southeast, 2021-05-03)
    • Message from the Chancellor: 2022-03-03

      Carey, Karen (University of Alaska Southeast, 2022-03-03)
    • Morainal Bank Evolution and Impact on Terminus Dynamics During a Tidewater Glacier Stillstand

      Eidam, E. F.; Sutherland, D. A.; Duncan, D.; Kienholz, Christian; Amundson, Jason M.; Motyka, R. J. (American Geophysical Union, 2020-09-25)
      Sedimentary processes are known to help facilitate tidewater glacier advance, but their role in modulating retreat is uncertain and poorly quantified. In this study we use repeated seafloor bathymetric surveys and satellite‐derived terminus positions from LeConte Glacier, Alaska, to evaluate the evolution of a morainal bank and related changes in terminus dynamics over a 17‐year period. The glacier experienced a rapid retreat between 1994 and 1999, before stabilizing at a constriction in the fjord. Since then, the glacier terminus has remained stabilized while constructing a morainal bank up to 140 m high in water depths of 240–260 m, with rates of sediment delivery of 3.3 Å~ 105 to 3.8 Å~ 105 m3 a−1. Based on repeated interannual surveys between 2016 and 2018, the moraine is a dynamic feature characterized by push ridges, evidence of active gravity flows, and bulldozing by the glacier at rates of up to meters per day. Beginning in 2016, the summertime terminus has become increasingly retracted, revealing a newly emerging basin potentially signaling the onset of renewed retreat. Between 2000 and 2016, the growing moraine reduced the exposed submarine area of the terminus by up to 22%, altered the geometry of the terminus during seasonal advances, and altered the terminus stress balance. These feedbacks for calving, melting, and ice flow likely represent mechanisms whereby moraine growth may delay glacier retreat, in a system where readvance is unlikely.
    • The morphology of supraglacial lake ogives

      Darnell, K.N.; Amundson, Jason M.; Cathles, L.M.; MacAyeal, D.R. (International Glaciological Society, 2013-02-12)
      Supraglacial lakes on grounded regions of the Greenland and Antarctic ice sheets sometimes produce ‘lake ogives’ or banded structures that sweep downstream from the lakes. Using a variety of remote-sensing data, we demonstrate that lake ogives originate from supraglacial lakes that form each year in the same bedrock-fixed location near the equilibrium-line altitude. As the ice flows underneath one of these lakes, an ‘image’ of the lake is imprinted on the ice surface both by summer- season ablation and by superimposed ice (lake ice) formation. Ogives associated with a lake are sequenced in time, with the downstream ogives being the oldest, and with spatial separation equal to the local annual ice displacement. In addition, lake ogives can have decimeter- to meter-scale topographic relief, much like wave ogives that form below icefalls on alpine glaciers. Our observations highlight the fact that lake ogives, and other related surface features, are a consequence of hydrological processes in a bedrock-fixed reference frame. These features should arise naturally from physically based thermodynamic models of supraglacial water transport, and thus they may serve as fiducial features that help to test the performance of such models.
    • A multidisciplinary approach for generating globally consistent data on mesophotic, deep-pelagic, and bathyal biological communities.

      Woodall, L.C.; Andradi-Brown, D.A.; Brierley, A.S.; Clark, M.R.; Connelly, D.; Hall, R.A.; Howell, K.L.; Huvenne, V.A.I.; Linse, K.; Ross, R.E.; et al. (The Oceanography Society, 2018-04-02)
      Approaches to measuring marine biological parameters remain almost as diverse as the researchers who measure them. However, understanding the patterns of diversity in ocean life over different temporal and geographic scales requires consistent data and information on the potential environmental drivers. As a group of marine scientists from different disciplines, we suggest a formalized, consistent framework of 20 biological, chemical, physical, and socioeconomic parameters that we consider the most important for describing environmental and biological variability. We call our proposed framework the General Ocean Survey and Sampling Iterative Protocol (GOSSIP). We hope that this framework will establish a consistent approach to data collection, enabling further collaboration between marine scientists from different disciplines to advance knowledge of the ocean (deep-sea and mesophotic coral ecosystems).
    • Multisensory Issues in Students with Autism: A Meta-Synthesis

      Chambless, Michelle Lindsey (University of Alaska Southeast, 2016)
      For students with autism sensory processing issues are not an uncommon experience. There are three types of sensory processing categories. They are sensory under responsiveness, sensory over-responsiveness and sensory seeking. These sensory processing difficulties may affect social communication, impact daily life skills, include self-injurious behaviors, and create or add to anxiety already being felt by autistic students. These categories are not mutually exclusive and some students may experience all of these problems while others may only struggle with one or two. There is no one answer for students with autism but it is a collection of effects that form the student’s identity for their entire life. This meta-synthesis of the literature on sensory issues for students with autism explores the ups and downs of students struggling with sensory issues in hope to make navigating them easier.
    • Music Therapy; The Assisting Power to Manage Disability: A Meta-Synthesis

      Baczuk, Mindi (University of Alaska Southeast, 2018)
      The purpose of this meta-synthesis is to define and describe music therapy and how music therapy can assist individuals with special needs. Defined by the World Federation of Music Therapy, music therapy is “the use of music and/or its musical elements (sound, rhythm, melody and harmony) by a qualified music therapist, with a client or group, in a process designed to facilitate and promote communication, relationships, learning, mobilization, expression, organization and other relevant therapeutic objectives in order to meet physical, emotional, mental, social and cognitive needs.” (Ueda, et al, 2013). A music therapist is a trained individual who works with people with special needs to help assist them with life difficulties. Music therapy, along with other forms of treatment, can benefit an individual by allowing them the greater advantage of a comprehensive intervention program. The articles discussed in this meta-synthesis address the profession of music therapy and the effect it can have on individuals from birth to adulthood.