• I hear what you're saying: evaluating the couple validation training (CVT), a brief behavioral intervention

      McKay, Jessica; Worrall, Michael J.; Gifford, Valerie; Lopez, Ellen; Eldridge, Gloria; Fitterling, James (2020-12)
      Couple distress has strong implications for individual, couple, and family functioning. Research has found couple relationship education to be an effective tool in alleviating couple distress, thus improving the quality of couple communication and problem-solving skills. Couple relationship education has been shown to be more cost-effective and less likely to provoke the typical fears couples face when considering couple therapy, increasing the likelihood of receiving needed help. This study used a brief, highly structured behavioral intervention to teach partners to identify and code effective and ineffective ways of communicating. The primary research question sought to determine whether learning a structured coding process would lead to observable behavior changes through increased use of validating communication behaviors and decreased use of invalidating communication behaviors during a conflict-based discussion with a partner. Secondary questions pertaining to effective communication, relationship satisfaction, and training satisfaction were also explored. Participants were 16 couples who identified as being in a committed (nonmarried), heterosexual relationship, ages 18-40 (M = 26.00, SD = 6.61), and who were interested in improving their communication skills. The study used a quasi-experimental, three-level multilevel model to assess for dependence and change in the dependent variable (communication behaviors) over time. Hypothesis testing using the multilevel model found a significant difference between intervention and control groups pre to post workshop. However, inconsistent with the hypothesis the control condition increased validations significantly while the intervention condition showed no significant change over time. No other significant difference between groups were found. Other areas of interest emerged from the data. Couples self-reported a benefit from engaging in the study; over 85% of couples reported feeling satisfied with their experiences in the workshop and gave positive feedback about their experience. Future studies may explore the mechanisms of change and the possibility of additional clinically relevant changes which are not measured in this study. Keywords: relationship education, couples, validation, invalidation.
    • Identifying spatial patterns of storm driven flooding and erosion at Nelson Lagoon, Alaska

      Bogardus, Reyce C.; Maio, Chris; Mann, Daniel; Overbeck, Jacquelyn (2021-05)
      This project quantifies localized potential for shoreline change and flooding at Nelson Lagoon, a small fishing community located on the Bering Sea coast of the Alaska Peninsula. The overall goal of this project is to generate societally relevant and locally applicable map and data products through synergistic relationships with federal, state, private, tribal, and public partners. This project intends to substantiate anecdotal observations by local residents, with the ultimate goal of informing erosion and flooding mitigation efforts moving forward. Long-term trends of shoreline change were measured using multi-temporal orthorectified aerial imagery between 1983 and 2019, while annual changes in shoreline morphology were measured via cross-shore elevation profiles using a survey grade Real-time-Kinematic Global Navigational Satellite System (RTK-GNSS). Shoreline positions were extrapolated using linear regression techniques. A digital surface model (DSM) of the community was derived using Structure-from-Motion (SfM) with >2,400 aerial images collected with an Unmanned Aerial Vehicle (UAV) and used to assess flooding vulnerability after being geodetically referenced and related to a local tidal datum computed by this project. New and existing topographic and bathymetric datasets were compiled and refined into a 6,000 km² topobathymetric "seamless elevation" model of the Nelson Lagoon area, over which storm-tide induced currents were simulated using Delft3D FM Suite HMWQ. Remote sensing records indicate that the Nelson Lagoon spit elongated by more than 800 m and narrowed with an average Net Shoreline Movement (NSM) of -16.9 m between 1983 and 2019 (distal end not included). Though, NSM values show high variability ([sigma] = 21.9 m) and the lagoon and seaward sides of the spit are exhibiting very different erosional regimes. On both sides of the spit, episodes of rapid erosion mainly occurred during high storm-tide events that coincided with significant wave action. For this reason, the long-term erosion rates ultimately reflect the combined erosional impact of just a few storm events. Sand dunes in the supratidal zone on both sides of the spit are eroding at the vegetation line while the dune face retreats landward. By assessing erosion and flooding vulnerabilities for the Nelson Lagoon community, this study adds to an ever-growing database of such assessments statewide; which, ultimately, advance our understanding of regional coastal change in a shifting environment.
    • If women were dragons: a study of the conquest of women and dragons in Ragnar's saga, the Volsunga sagas, and the Nibelungenlied

      Baalke, Claire-Elise A.; Harney, Eileen; Stanley, Sarah; Riley, Terry (2020-08)
      This thesis is a study displaying the connections between female characters and dragons in Old Norse and Middle High Germanic literature. The main associations that I examine are the ways that female characters and dragons share the characteristics of greed or hoarding, prophetic sight or supernatural power, and "monstrosity" or "Otherness." The fundamental argument is that the women and dragons have common characteristics which define them as dangerous and thereby cause the men or heroes of the tale to feel the need to silence or depower them through conquest. Typically, the dragon is the barrier between the woman and the hero in these kinds of stories and thus the dragon is violated or slain in a manner that represents quashing of feminine power. I argue that the dragon is defeated as proxy to the defamation or depowering of deviant female characters, non-conforming women who do not follow socially accepted gender roles. The texts used to present these arguments are The Poetic Edda, The Volsunga Sagas and its prequel Ragnar's Saga, and The Nibelungenlied. In the majority of dragon stories there is a direct relationship between a dragon and a female character, commonly a princess who is being protected or arguably kept captive by the dragon. I argue, however, that these characteristics of the dragon, which are imitated by female characters, can manifest metaphorically as well. In the texts considered in which there are no "real" or physical dragons, a woman stands in as the metaphorical dragon that must be defeated.
    • Iliamna Lake ethnogeography: Yup'ik place names and sense of place

      Kugo, Yoko; Charles, Walkie; Ehrlander, Mary; Holton, Gary; Koskey, Michael; McCartney, Leslie (2021-05)
      This dissertation explores Iliamna Lake ethnogeography, the physical and mental understanding of the landscape, by researching Yup'ik place names and stories about these places from Iliamna Lake Yup'ik perspectives (Yupiit iingitgun). Many Yup'ik place names were forgotten after Euro-Americans arrived and introduced modern education in the early twentieth century. Some Iliamna Lake Yup'ik Elders remember Indigenous place names even though the subsistence resources in the places have declined or they no longer travel there due to environmental and cultural changes. Prompted by the declining population of Iliamna Lake Yup'ik speakers, along with their knowledge, the Iliamna Lake communities requested this study of Iliamna Lake Yup'ik place names and narratives about the places. Using two methods, oral history and a community-based participatory approach, the community participants and the author recorded 219 Yup'ik and over 100 contemporary place names during eight ethnographic field trips conducted from 2016 to 2019. This dissertation used two analytical methods--grounded theory and mindful inquiry--to categorize place names in themes that are relevant to Iliamna Lake community perspectives. This research revealed that place names and stories about these places illustrate community histories, lifeways, and cultural ethics and practices that are grounded in the people's intimate relationships with their homeland. Telling and retelling these stories enables the people to visualize their landscape, while affirming and reinforcing the knowledge and practices that have enabled the Yup'ik people to survive and thrive in the region for many generations. Ethnogeography addresses how these cultural landscapes intertwine with local histories and changes in land use from insider perspectives. Yup'ik names and stories related to these places act as mnemonic pegs or mental landmarks that assist the people in commemorating and continuing to navigate within their homelands. Maintaining their place names with accounts about these places supports Iliamna Lake residents in continuing to share their geographic knowledge, cultural practices, Yugcetun (Central Yup'ik language), and community histories, thereby enhancing community cohesiveness, which in turn promotes community and ecological well-being.
    • Impacts of climate change on juvenile broad whitefish Coregonus nasus in Arctic Alaska: bioenergetics model development and application

      Green, Duncan G.; Sutton, Trent M.; Norcross, Brenda L.; Cunningham, Curry J. (2020-08)
      Anthropogenic climate change is contributing to rising temperatures worldwide, yet the increase is particularly rapid in the Arctic. Despite their position on the front of global temperature warming, the responses of Arctic ecosystems and the individual species within them are poorly understood. Broad whitefish Coregonus nasus in the Alaska nearshore Beaufort Sea not only inhabit a rapidly changing ecosystem, but are also a key component of subsistence harvest in the region and a relatively understudied fish. I parameterized and corroborated a bioenergetics model through species-specific physiological investigation and laboratory rearing trials, and used the resulting model to simulate potential responses in growth and consumption under climate change scenarios projected with global climate models. Simulations at current estimated prey energy densities projected increases in future consumption rates of up to 4% required to maintain historically observed summer growth, while simulations in which prey energy density was reduced by 50% resulted in projected consumption increases of up to 107% necessary to maintain historic growth. Simulations in which prey energy density was increased by 50% indicated the ability for juvenile broad whitefish to reduce consumption rates by up to 32% and maintain current growth rates. These results suggest that, although the physiological effects of rising water temperatures have the potential to increase growth rates of juvenile broad whitefish, climate-induced shifts in prey availability or prey quality are likely to be regulating factors that determine the magnitude and direction of changes in growth rates.
    • In pursuit of harm reduction in the Alaskan context: patient cultural explanatory models of addiction and treatment outcomes for a medically-assisted program utilizing a buprenorphine/naloxone formulation

      Vasquez, Ángel R.; Campbell, Kendra; Lopez, Ellen; Gifford, Valerie; Gonzalez, Vivian (2020-08)
      This study explored the process of completing a private-for-profit medically-assisted treatment (MAT) program which treats opioid use disorder in a semi-rural community in Alaska. The goal of the study was to answer two broad research questions: (a) did patients get better during the medically-assisted treatment program, and (b) what characterized patient experiences participating in the MAT program? Limited research has been conducted to understand patient experiences of completing medically-assisted treatment in small communities and how various factors may impact treatment outcomes and recovery trajectories. To achieve this goal, a mixed methods case study approach was conducted to evaluate changes in symptom distress and characterize the experience of patients who participated in the program. Three Phases were implemented. Phase I involved archival data analysis of a 22 patient dataset was conducted to assess pre-post treatment outcomes. In Phase II three participants were interviewed who initiated in the program to explore patient treatment themes. Phase III involved co-interpretation of preliminary findings MAT program providers to synthesize findings and gain insights into systemic factors that may have impacted participant experiences. The three-phase research study revealed three major findings. First, MAT patient program completers in our sample who utilized buprenorphine/naloxone in conjunction with counseling experienced a statistically significant reduction in psychological distress with a large observed effect size (Phase I). Second, themes that emerged from semi-structured interviews suggest motivation and treatment process factors play an important role in treatment success (Phase II). Finally, community stakeholders on the provider treatment team were consulted to more deeply understand why it is important to assess patient needs and co-interpret key study findings (Phase III).
    • Influence of environmental attributes on intertidal community structure in glacial estuaries

      McCabe, Mary K.; Konar, Brenda; Iken, Katrin; Kelley, Amanda (2021-05)
      High-latitude coastal environments are experiencing dramatic changes due to climate warming. Increased glacier discharge rates modulate downstream environmental conditions in coastal watersheds. These fast-changing environments are predicted to influence the structure of nearshore marine communities. Here, rocky intertidal community structure, recruitment of key organisms, and environmental correlates were examined at nine watersheds in two regions (Kachemak Bay and Lynn Canal) that bookend the Gulf of Alaska, which were separated by approximately 1000km. Each watershed was part of a gradient in each of the regions that spanned 0-60% glacial coverage. Percent cover, biomass surveys, and recruitment of intertidal organisms, along with environmental monitoring of salinity, temperature, dissolved oxygen, river discharge, turbidity, and nutrient loading were completed from April - September 2019 in each watershed. Biological community structure and variance were analyzed by taxa and by ecological group (i.e., primary producer, filter feeder, omnivore, grazer, predator) and then in relation to the local environmental spatiotemporal profiles. In general, larger watersheds with more glacial coverage and river discharge resulted in higher cover of primary producers and less cover of filter feeders. This pattern was more apparent in the region with more oceanic influence as compared to the other region located within an inlet. In relation to specific environmental drivers, salinity was negatively correlated with primary producer cover (r = -0.52), but positively associated with barnacle cover (r = 0.40). Additionally, turbidity was positively correlated with primary producer biomass (r = 0.50), but negatively correlated with mussel cover (r = -0.30). In contrast, there was a positive relationship among mussel recruitment and discharge and turbidity. There was variability in within-ecological group response between regions that could be a response to local circulation and oceanic influences. Barnacles were the main filter feeder species driving patterns in the more saline region located close to the open ocean, while mussels drove patterns in the other less oceanic region. As glaciers recede, environmental conditions, such as salinity, will increase and turbidity will decrease, which may alter future intertidal community assemblages dominated by filter feeders.
    • Integration of remote sensing technologies into Arctic oil spill response

      Garron, Jessica I.; Meyer, Franz; Trainor, Sarah; La Belle-Hamer, Nettie; Lee, Olivia; Mahoney, Andrew (2020-12)
      Identifying the tools and pathways to successful integration of landscape level science into decision-making processes is vital for quality environmental stewardship. Remote sensing information can provide critical facts to decision makers that historically were only available via manned airplane flights and ground truthing expeditions. Remote locations like the Arctic are well suited for monitoring with remote sensing tools due to the lack of transportation infrastructure and communications bandwidth. Remote sensing tools can be valuable when monitoring specific Arctic targets like ocean going vessels, sea ice, coastal erosion, off-shore resource development infrastructure, and oil spills. This dissertation addresses how to mount a more efficient and informed response to Arctic oil spills by capitalizing on available RS tools. I posed three research questions to frame this work, 1) What remote sensing tools are currently available, as compared to those currently used in the Incident Command Structure of an oil spill response? 2) Are there barriers to additional remote sensing tool use for oil spill response support? 3) What process changes can improve or increase remote sensing data use in oil spill detection and response? I conducted a four-phased, exploratory sequential mixed methodological study to examine current remote sensing capacity and solutions to expand remote sensing use in support of oil spill response. Phase One defined the remote sensing tools available to support oil spill response, identified how those tools are being used in support of oil spill response actions, and was used as the foundational research to inform the following phases of the study. Phase Two used cloud-processing resources to establish an automated oil detection pipeline. Phase Three addressed human-driven barriers to remote sensing tool use identified in phase one through remote sensing tool training, knowledge coproduction, and remote sensing data integration into oil spill response exercises. Synthesizing all components of Phases One, Two and Three, a remote sensing protocol for the use of unmanned aircraft systems in support of oil spill response was developed and integrated into U.S. Coast Guard operational policy in Alaska to complete Phase Four of this research. This research identifies opportunities and solutions that support improved Arctic oil spill response decision-making through the application of remote sensing data and information.
    • Investigation of variability of internal tides in the Tasman Sea

      Brazhnikov, Dmitry; Simmons, Harper; Kowalik, Zygmunt; Johnson, Mark; Marchenko, Alexey; Horrillo, Juan J. (2021-05)
      Surface tides, when obstructed by bottom relief, give rise to periodic oscillations within the stratified oceanic interior. Such transformation of the depth independent (barotropic) tide into internally propagating (baroclinic) waves comprises 1/3 of the global energy losses from the surface tide. Internal waves of tidal period known as internal tides tend to have low vertical shear and hence are very stable and long lived. They have been observed to propagate essentially unchanged across ocean basins. Details of the internal tide wave life-cycle are not well known, yet turbulent dissipation powered by the slow decay of these waves is one of the key processes shaping deep ocean water properties. The Tasman Sea stands out as a natural laboratory to investigate the internal tide life cycle. In this dissertation, the generation and propagation of internal tides were examined by means of realistic simulations of ocean circulation under varying conditions, and were compared to observations obtained during the Tasman Tidal Dissipation Experiment (TTIDE). The simulations reveal that the barotropic-to-baroclinic conversion is intensified at the Macquarie Ridge near New Zealand by coupling with secondary, nonlocally produced internal tides. Because of this complexity, regionally varying hydrographic conditions drive remarkable temporal and spatial variability of internal tide generation. The internal tides that are created at the ridge constructively superpose into a spatially confined, beam-like feature (Tasman beam) that radiates across the Tasman Sea over 1000 kilometers from its generation region and reaches the Tasman shelf. The beam is described well at first order by simple plane wave propagation theory, but also exhibits non-plane wave characteristics associated with diffraction. Additional intricacy arises from development of a standing wave, the result of the beam's reflection near Tasmania. Temporal changes include hydrography-induced refraction and strong perturbations from interactions with eddies. It is concluded that in-situ mooring measurements and ship surveys of internal tides exhibit a great deal of apparent spatial and temporal variability that can be difficult to interpret. This variability can largely be eliminated in the analysis of numerical models which allow the underlying wave field energy life cycle to be quantified.
    • Investigations on the impacts of ship traffic in the Bering Sea on aerosol optical depth using automatic identification systems data, and MODIS collection 6.1 data

      Summers, Tyler; Mölders, Nicole; Friberg, Mariel; Fochesatto, Javier (2021-05)
      Increasing Arctic shipping requires study of the increasing aerosol emissions impact on aerosol optical depth (AOD) in the Bering Sea and the Bering Strait. This study used Moderate Resolution Imaging Spectroradiometer (MODIS) 550 nm AOD 3 km products to study the seasonal variability over the length of the Arctic shipping season, from June to October, over 2011 and 2014. Bucket resampling was used to project and downscale the MODIS AOD to a 0:25 by 0:25 grid during overpasses. An overpass is dened as consecutive MODIS granules from both the Terra and Aqua satellites. Ship positional data obtained from automatic identication systems (AIS) was aggregated to hourly data. Collocation of ships and AOD from overpasses were determined for all quarter degree grid cells and times. Area-weighted means for both grid-cells with ship occurrence and without ships were determined for each month. AOD decreases with increasing time in the shipping season due to the increasing frequency of low pressure system and hence aerosol removal via washout and scavenging. Comparison of the AOD of 2011 and 2014 revealed that the position of the Aleutian Low not only strongly aects the sample size, but also AOD over the Bering Sea. The sea-ice area seemed to be without notable impact on the number of ships and AOD. A weak positive correlation was found between AOD and the number of ships present in the same grid cell during a overpass for 7 out of the 10 months. A strong skewing towards October occurred in 2011 due to a strong positive correlation of the number of data points.
    • It's complicated: immigrant parents in Alaska navigating the process of raising bilingual children

      Dosch, Katerina; Sickmann, Sabine; Marlow, Patrick; Martelle, Wendy (2021-05)
      This qualitative study investigates the process of raising bilingual children in Fairbanks, Alaska. The study was guided by an overarching question: Why do some children in bilingual families become bilingual speakers, whereas other children who also have the chance to become bilingual do not? From that, two main research questions have evolved. 1. What are the elements involved in raising bilingual children in Fairbanks, Alaska as reported by the parents? 2. What is the role of a family's place of residence on their children's bilingualism? Data were collected through a socio- demographic questionnaire, semi-structured in-depth interviews, and focus groups. Three rounds of interviews were conducted with each participating family - an initial interview, a follow up interview, and a focus group interview. Seven families participated in the study and only parents were interviewed. These families consisted of either first generation immigrant parents (sharing or not sharing the same native language) or parents in mixed marriages (immigrants married to native- born Americans). Over 19 hours of data were audio recorded, manually transcribed ad verbum, and analyzed. From the method of grounded theory data coding, groups of elements that are involved in the process of raising bilingual children and the development of children's heritage language (HL) emerged, namely: parental and children's HL related actions, factors influencing bilingualism, factors determining bilingualism, and place of residence. The findings suggest that the process of raising bilingual children is positively or negatively influenced and determined by a complex net of interconnected elements. Raising bilingual children, thus, rests on a combination of supportive and detrimental elements, which are in a constant struggle. It seems that the process of raising bilingual children can absorb a certain amount of detrimental elements without collapsing. Considering the elements involved in raising bilingual children, it is not only parents and their actions that play an important role in the process of raising bilingual children. While parents are the instigators of the process, children greatly influence parental actions connected to the transmission of the HL. The findings of this study suggest though, that children and their actions alone do not decide if the process fails or succeeds. Parents seem to be able to mitigate children's detrimental influences (if they exist) through their consistent use of the HL. On the other hand, some parents hinder their own efforts either through their fears, beliefs, or other personal limitations. Finally, based on the data, place of residence does not seem to play a significant role in the process. Some parents are able to raise bilingual children despite living in a place that poses challenges to bilingual families. These parents are able to overcome obstacles through their own efforts and consistency of the HL use.
    • Landscape characteristics influence climate change effects on juvenile chinook and coho salmon rearing habitat in the Kenai River watershed

      Meyer, Benjamin; Rinella, Daniel; Wipfli, Mark; Schoen, Erik; Falke, Jeffrey (2020-08)
      Changes in temperature and precipitation as a result of ongoing climate warming in south-central Alaska are affecting juvenile salmon rearing habitat differently across watersheds. Work presented here simulates summer growth rates of juvenile Chinook and coho salmon in streams under future climate and feeding scenarios in the Kenai River (Alaska) watershed across a spectrum of landscape settings from lowland to glacially-influenced. I used field-derived data on water temperature, diet, and body size as inputs to bioenergetics models to simulate growth for the 2030-2039 and 2060-2069 time periods, comparing back to 2010-2019. My results suggest decreasing growth rates under most future scenarios; predicted changes were of lower magnitude in the cooler glacial watershed and main stem and more in montane and lowland watersheds. The results demonstrate how stream and landscape types differentially filter a climate signal to juvenile rearing salmon habitat and contribute to a broader portfolio of habitats in early life stages. Additionally, I examined two years of summer water temperature data from sites throughout our study tributaries to assess the degree to which lower-reach sites are representative of upstream thermal regimes. I found that the lower reaches in the lowland and glacial study watersheds were reasonably representative of daily and seasonal main stem thermal conditions upstream, while in the montane study watershed (elevation and gradient mid-way between the lowland watershed) upstream conditions were less consistent and thus less suitable for thermal characterization by a lower-reach site alone. Together, this work highlights examples of the importance of accounting for habitat diversity when assessing climate change impacts to salmon-bearing streams.
    • Life cycles of the kelps Saccharina latissima and Alaria marginata: implications for mariculture and ecology in Alaska

      Raymond, Annie E.T.; Stekoll, Michael S.; Eckert, Ginny L.; Bergstrom, Carolyn A. (2020-08)
      Kelp farming has the potential to economically diversify coastal communities of Alaska while offering other ecosystem services, including carbon sequestration and mitigation of eutrophication. Two bottlenecks to the expansion of the industry are understanding the natural kelp life cycle and manipulating the life cycle to produce seed. We address these questions with specific research aimed to increase knowledge of the expected natural variability of the kelp life cycle and test methods to effectively manipulate storage of kelp seed string to add flexibility to the kelp farming industry. First, in Chapter 1, we documented the patterns of sporophyte fertility for two commercially important kelp species, Saccharina latissima and Alaria marginata, in the wild. We found S. latissima exhibited both annual and perennial life history varying by location and year, with an increasing proportion of fertile sporophytes present in the fall and winter season. In contrast, A. marginata displayed a predictable annual life history, recruiting in spring with the proportion of fertile sporophytes increasing into the fall. Results from Chapter 1 suggest A. marginata has a more reliable brood stock availability and, therefore, has the potential to be a suitable commercial crop. Ecologically, Chapter 1 results suggest A. marginata may contribute consistently to habitat across Alaska in spring and summer months. In Chapter 2, we tested how different culture conditions, including light, temperature, and culture media, affected gametophyte growth with the goal of developing storage methods for kelp seed string. We found that low temperature is effective in slowing gametophyte growth and reducing gametogenesis and is the best condition for seed storage. Further experiments tested how storage in cold temperatures affects seed quality, leading to the development of a method called "cold banking," which enables extended seed storage or staggering of seed string for at least an additional thirty-six days in a storage setting without adverse effects to sporophyte density and length at the time of outplanting and up to three weeks after outplanting. Ecologically, Chapter 2 results demonstrate the diversification of microscopic stages used as an overwintering strategy by S. latissima. As the kelp mariculture industry is expected to grow in Alaska and around the world, we hope this information will be a jumping-off point for research promoting productive and sustainable commercial kelp production.
    • Long-term shifts in community structure, growth, and relative abundance of nearshore Arctic fishes: a response to changing environmental conditions

      Priest, Justin T.; Sutton, Trent M.; Mueter, Franz J.; Raborn, Scott W. (2020-08)
      Environmental conditions influence the presence, species composition, abundance, and growth of fish species in the nearshore Arctic ecosystem. With ongoing shifts in Arctic conditions due to climate change, how fish communities and individual species respond to such changes to environmental variability more broadly is unknown. This study analyzed catch and length data from a long-term fish monitoring project near Prudhoe Bay, Alaska, 2001-2018, to quantify the effects of environmental variables on the overall fish community and on the juveniles of two important whitefishes, Arctic Cisco Coregonus autumnalis and Broad Whitefish Coregonus nasus. Abundance data (n = 1.78 million fish) from daily sampling (July-August) at four stationary sampling locations showed distinct shifts in fish community metrics. Since 2001, annual species richness has significantly increased by one species per decade while water temperature warmed by over 1.4°C. The species composition based on biweekly catch data has significantly changed across years, with distinct variations among sample locations and throughout the season. Species composition was significantly affected by both salinity and water temperature. The effects of environmental conditions on growth showed that water temperature was positively and linearly associated with increases in growth for juvenile whitefish, while salinity negatively affected growth of age-0 Arctic Cisco. Changes in the abundance of juvenile whitefishes were related to both water temperature and salinity. Results from all analyses suggest that species positively associated with observed warming in the aquatic environment are generalist species such as Broad Whitefish. This study concluded that continued climate change, and especially Arctic warming, will likely increase growth, change the species composition, and alter abundance in the Arctic nearshore ecosystem. These changes will have impacts on subsistence harvests and on upper trophic level species that prey on nearshore fishes.
    • Mental health problems in the mountains: needs, assets, and recommendations for managing mental health problems in mountain-focused wilderness-based education and related fields

      Johnson, Samuel H.; Dulin, Patrick L.; Lopez, Ellen D. S.; Gifford, Valerie M.; Rivkin, Inna D. (2020-08)
      Background: Through controlled exposure to stress, wilderness-based education programs can buildcapacity for adaptive coping and produce long lasting improvements to participants' quality of life.However, stress can also overwhelm them, resulting in the emergence and exacerbation of mental health vulnerabilities in the field. However, empirically grounded best practices for training, pre-trip screening, and protocol/policy for mental health specific to the wilderness context are not well developed. Aim: The aim of this study was to assess needs and assets, and develop recommendations for training, pre-trip screening, and organizational protocol/policy to assist with successful management of mental health problems in mountain-focused, wilderness-based education and related fields such as outdoor leadership, guiding, environmental education, snow safety, search and rescue, and wilderness therapy. Methods:A pragmatic, two phase, sequential mixed methods approach was utilized to explore this topic within the context of an overarching collaborative community based participatory research (CBPR) framework with organizational partners: National Outdoor Leadership School, Outward Bound USA and Canada, the Wilderness Risk Management Conference, and the Alaska Mountaineering School. A preliminary quantitative study utilized a cloud-based survey to determine baseline characteristics for 64 wilderness-based educators, guides, outdoor leaders, snow safety professionals, and search and rescue personnel. Qualitative interviews with 16 experienced and prepared key informants addressed the study aim in more depth, consistent with partnering organization priorities, in the tradition of CBPR. Findings: Mental health topics and skills are underemphasized in current training, and training was found to be of less value than personal and professional experiences with mental health. In the future, mental health should be increased and emphasized, possibly through the utilization of existing resources such as the stress continuum or curriculum such as Psychological First Aid as well as practical training opportunities that emphasize experiential learning around mental health. Current screening can present both risks and benefits for clients, instructors, and organizations. Nondisclosure and the impacts of stigma and prejudice on the interpretation and utilization of mental health screening information were major concerns. However, screening can guide preventive and proactive efforts, and build working relationships with potential participants. Future screening should be used to inform participants about course stress, encourage disclosure, and direct curriculum development. Multi-step screening, utilizing multiple interactions with participants before the course, was identified as a utilitarian way to facilitate improvements for future screening. In protocol/policy, field management of mental health problems is underemphasized relative to evacuation, resulting in overutilization of disruptive evacuation processes. While many organizations do well at responding to instructor mental health needs after incidents such as a fatality in the line of work, inconsistencies in implementation can create unintended barriers to instructor self-care. Future protocol/policy should prioritize instructor mental health by addressing inconsistencies in implementation, removing barriers to self-care and guiding the deployment of resources such as responsive staffing or free counseling benefits. Implications: This study contributes uniquely to the literature by providing an empirically-based perspective into a little researched topic, and multiple avenues for implementation of findings such as increasing mental health content and experience-based training, utilization of multi-step screening processes, and consistent implementation of organizational protocol/policy in support of client and instructor mental health. Recommendations for implementation address weaknesses and build upon strengths already present in training, screening, and protocol/policy. Overall, practice and research in this area are in need of further investigation and development. Future dissemination, research, and practice development could help develop measures or resources to support the improvement of training, screening, and protocol/policy across wilderness-based education and related fields.
    • Metabolite influence on the hibernating Arctic ground squirrel

      Rice, Sarah A.; Drew, Kelly; Kuhn, Thomas; Coker, Robert; Ritter, Robert (2020-12)
      Hibernation is a state of extreme metabolic plasticity and fasting. How hibernators maintain nitrogen homeostasis and regulate amino acid metabolism and how those metabolites influence hibernation physiology remains unknown. We first utilized three approaches to understand nitrogen homeostasis and amino acid metabolism in hibernation: longitudinal metabolic profiling within individual animals over undisturbed torpor, in vivo amino acid isotope tracing in deep torpor, and ¹⁵N isotope tracing in vivo during arousal from hibernation in Arctic Ground Squirrels (AGS). We observed that in vivo whole body production (WBP) of metabolites in deep torpor are profoundly and selectively suppressed in deep torpor. Metabolic profiling over undisturbed torpor bouts shows amino acids with nitrogenous side chains accumulate over torpor while urea cycle intermediates remain unchanged. During arousal from hibernation, ¹⁵N isotope tracing demonstrates recycling of free nitrogen into non-essential amino acids, essential amino acids and the gamma-glutamyl system. We next utilized two approaches to understand potential metabolite influences on thermogenesis and behavior in hibernation: we infused ammonium acetate in deep torpor and fed diets high in omega 3 fatty acids and monitored body temperature and torpor bout length. We found high doses of a nitrogen donor, ammonium acetate, as well as diets high in omega 3 fatty acids both influence thermogenesis in hibernation. In conclusion, production of metabolites in deep torpor indicate highly regulated metabolism with accumulation of nitrogen carrying amino acids. We additionally show metabolites and nitrogen can exert thermogenic influence on hibernating AGS.
    • Meteorological drivers of lightning in Alaska on seasonal and sub-seasonal timescales

      Chriest, Jonathan; Bhatt, Uma S.; Bieniek, Peter A.; Walsh, John E. (2021-05)
      Wildfire has long been a part of the Boreal forest ecosystem in Alaska and the increasing number of large fire seasons over the past 2 decades has had substantial economic and health impacts. Boreal wildfires are expected to continue to increase over the next century in part due to a projected increase in lightning. This motivates developing lightning outlooks to inform fire management decisions regarding the economic allocation of shared firefighting resources including but not limited to personnel and air tankers. The goal of this research is to identify key meteorological parameters associated with lightning processes on a stroke-by-stroke spatial scale and at hourly-to-sub-seasonal timescales. This is a first step towards developing robust lightning outlooks. In order to identify the key parameters, lightning data for the Alaska Lightning Detection Network was paired with hourly European Center Reanalysis Version 5 (ERA5) over the 2012-2019 study period. This data was analyzed on the scale of Alaska Fire Service Predictive Service Areas (PSAs) and three sub-seasons of the Alaska fire season. This strategy helped to identify regional and sub-seasonal variability and made the research operationally relevant. Key results from this research include the following. The majority of lightning occurs in the duff driven sub-season across all PSAs. Lightning, particularly in the Interior PSAs, follows a diurnal pattern with lightning on average beginning earlier in the day in the eastern portion of Alaska and later in the day in the western portion of Alaska. This distinctive pattern is not as well defined in the Coastal PSAs. Results also suggested that dry lightning may be more prevalent in portions of the western Interior than in other regions of Alaska. Lightning events were more common under specific atmospheric flow directions at 500 and 700 hPa, where these directions varied by PSA. Northeasterly and northwesterly flow aloft were most favorable for lightning in the Tanana Valley West PSA, while southerly flow aloft was more favorable for lightning in the North Slope and Upper Yukon PSAs. Finally, easterly flow was a more common pattern during lightning strokes in the Seward Peninsula and Kuskokwim Valley PSAs.
    • Modeling permafrost dynamics and water balance of Arctic watersheds in a changing climate

      Debolskiy, Matvey Vladimirovich; Hock, Regine; Romanovsky, Vladimir E.; Alexeev, Vladimir A.; Nicolsky, Dmitry J. (2020-12)
      Changes in climate across the Arctic in recent decades and especially the increase of near-surface air temperature promote signicant changes in key natural components of the Arctic including permafrost (defined as soil experiencing subzero temperature for more than two consecutive years). Recent borehole observations exhibit signicant increase in ground temperatures below the depths of seasonal variations. Modeling studies on a global scale suggest a steady decrease in area underlain by near-surface permafrost in the northern hemisphere in recent decades. Global projections for the next century predict further permafrost degradation depending on the greenhouse gas concentration trajectory. Permafrost degradation is not only associated with climate feedbacks but can also result in signicant changes in coastal and terrestrial ecosystems and increased risks of costly infrastructural damage for Arctic settlements. In addition, permafrost plays an important role in the terrestrial part of the Arctic freshwater cycle as the volumes of frozen ground are practically impermeable for subsurface moisture transport and contain excess water in the form of ground ice. Since geophysical observations bear signicant costs in the Arctic, especially in the remote areas, simulations performed with physically based numerical models allow researchers to assess the current state of permafrost in Arctic regions and make future projections of its dynamics and resulting hydrological impacts. In this dissertation we use numerical modeling in two distinct ways: 1) to estimate current and future ground temperature distribution with high resolution on a regional scale and 2) to evaluate the role permafrost degradation plays in changes in water balance of watersheds under changing climate. First, we study the permafrost evolution of the Seward Peninsula, Alaska over the 20th and 21st century using a distributed heat transfer model. Model parameters are calibrated with a variational data assimilation and are distributed across the study domain with an ecosystem type approach. Simulations suggest that the peninsula will experience a reduction in the near surface permafrost extent of up to 90% and an average increase in ground temperature across the peninsula up to 4.4°C towards the end of the 21st century under the high greenhouse gas concentration trajectory. Second, we perform an ensemble of millennia-long experiments by simulating hypothetical idealized small-scale watersheds placed in a typical Sub-Arctic setting with a physically based distributed hydrological model. In these experiments we single out the effects of temperature dependent subsurface moisture transport by applying air temperature change in our forcing scenarios only to sub-zero temperatures within a given year. Results suggest a long-term increase in annual runoff of 7-15% and a similar decrease in evapotranspiration under a prolonged (up to a millennia) air-temperature increase. The short-term (< 100 years) water balance response highly depends on soil permeability and the watersheds slope and profile curvature. The simulated changes in water balance are a direct result of the decrease in near- surface soil moisture and intensified subsurface moisture transport in the deeper soil layers due to the permafrost thaw. Additional experiments suggest that simplied models that do not include lateral subsurface moisture transport, as typically done in Earth System Models, can reproduce similar changes in equilibrium water balance to the ones predicted by more sophisticated models for the watersheds with gentle slopes. We also find that if the air temperature trend is reversed and watersheds are experiencing prolonged cooling, a high degree of hysteresis in water balance behavior can be observed, however, the long-term changes in water balance are equal in their amplitude. Additionally, we find that initial soil moisture distribution in the deeper soil which is essentially a consequence of the paleoclimate (given the same permeability and topography) determines the overall soil moisture storage deciency which in turn results in the lag between the onset of warming and the increase in total runoff. The deficit in soil moisture storage is highly dependent on the watersheds topography.
    • Paleocene depositional history of the Cretaceous-Paleogene impact basin, Yucatan Peninsula, Mexico

      O'Malley, Katherine E.; Whalen, Michael; Fowell, Sarah; McCarthy, Paul (2020-12)
      In the spring of 2016, the International Ocean Discovery Program set out on Expedition 364 to recover core from the peak ring of Chicxulub Impact Crater at Site M0077. In total, 829 m of core was collected spanning granite to Paleogene sedimentary rocks. From this core, we have a well-preserved record of the Paleocene, which represents ~10 million years post impact in just under 10 m of sedimentary rock record. This has presented an incredible research opportunity, as we have gained invaluable information on how the environment responded and recovered from the global catastrophe that was the Chicxulub Impact. The Paleocene at M0077 is highly condensed and comprised of predominantly pelagic carbonate rocks. High resolution core logging and thin section analysis were used to identify facies in the Paleocene. Facies include marlstone, argillaceous wackestone, foraminiferal wackestone, and rare coarser grained lithologies such as packstone and grainstone. Overall, the Paleocene exhibits a succession of rhythmically bedded cycles composed of marlstones grading to argillaceous wackestones and capped by foraminiferal wackestones. Coarser grained lithologies only exist in the lower and uppermost portion of the core. In total, 72 cycles that ranged from 5-30 cm thick are identified and grouped into six larger packages based on pattern similarities in color, lithology, ichnofabric indices, and geochemical data. These cycles are interpreted as parasequences, and show predictable stacking patterns that allow us to make sequence stratigraphic analyses. Each package represents one to two systems tracts, and some can be correlated to eustatic sea level change. Recorded in this core is the progression of an initial sea level lowstand immediately post impact, and the fluctuation between highstands, lowstands, and transgressive systems tracts that follow. Major and trace elements were analyzed throughout the core, as well as delta¹³Corg and delta¹⁵Nbulk values. Three sets of geochemical proxies (paleoredox, detrital input, productivity) were used to provide insight into paleoecological conditions. Initial conditions in the crater show a period of high productivity, which tapers off within a million years post impact. Redox conditions vary, and show one major anoxic event, with other enrichments likely representing periods of pore water euxinia or increases in stratification leading to a more robust redox gradient.
    • Photosensitized degradation of chlorothalonil and chlorpyrifos in the presence of Arctic derived dissolved organic matter

      Quesada, Ginna; Guerard, Jennifer; Rasley, Brian; Green, Thomas (2021-05)
      Pesticides used at mid latitudes can accumulate in Arctic environments. Two commonly detected pesticides in Arctic lakes are chlorothalonil and chlorpyrifos. In surface waters, photolysis can play an important role in the attenuation of contaminants. The chemical characteristics of dissolved organic matter (DOM) can further alter the extent of photolytic degradation of pollutants. To determine the relative effect of natural Arctic lake water and its DOM on the photolysis of chlorpyrifos, experiments were conducted under natural Arctic irradiation and under artificial irradiation. Similarly, the effect of Arctic DOM was investigated for chlorothalonil under artificial irradiation. The fulvic acid (FA) fraction of DOM was isolated from Fog 1 and from Toolik Lake in May and July. Lake waters significantly enhanced the photodegradation of chlorpyrifos under natural light by up to an order of magnitude. FA's significantly increased the degradation of chlorpyrifos (>2x) and chlorothalonil (>100x) under artificial irradiation relative to 18 MΩ-cm Water. Toolik Lake FA isolated in May, significantly enhanced the photolysis of both contaminants relative to the isolate collected in July. In the presence of iron, a lower ratio of carbohydrates and peptides to aromatics in the FA's was associated with faster degradation for chlorothalonil.