Arctic Ocean Physiography

The first order physiographic provinces of the Arctic Ocean has been defined using the recently updated International Bathymetric Chart of the Arctic Ocean (IBCAO) grid model as the main database and a semi-quantitative approach. The first step in our classification of physiographic provinces is an evaluation of seafloor gradients contained in a slope model that was derived from the IBCAO grid. The slope information reveals certain seafloor process-related features, which add to the bathymetric information. Using interactive 3D-visualization, the slope and bathymetric information were simultaneously analyzed and certain slope intervals of the Arctic Ocean seafloor were found to generally characterize major physiographic provinces. This information was used for the initial classification, although in certain locations gradual changes in bottom inclination made it difficult to detect transitions between some physiographic provinces, as for example, the transition between continental rise and slope, as well as between the rise and abyssal plain. In these cases some manual intervention was required guided by generated bathymetric profiles. The areas of the provinces we classified are individually calculated, and their morphologies are subsequently discussed in the context of the geologic evolution of the Arctic Ocean Basin as described in the published literature. In summary, our study: provides a physiographic classification of the Arctic Ocean sea floor according to the most up-to-date bathymetric model and addresses the geologic origin of the prominent features as well as provides areal computations of the defined first order physiographic provinces and of the most prominent second-order features

Hypsometry, Volume and Physiography of the Arctic Ocean and Their Paleoceanographic Implications

Recent analyses of the International Bathymetric Chart of the Arctic Ocean (IBCAO) grid model include: Hypsometry (the distribution of surface area at various depths); ocean volume distribution; and physiographic provinces [Jakobsson 2002; Jakobsson et al., in press]. The present paper summarizes the main results from these recent studies and expands on the paleoceanographic implications for the Arctic Ocean, which in this work is defined as the broad continental shelves of the Barents, Kara, Laptev, East Siberian and Chukchi Seas, the White Sea and the narrow continental shelves of the Beaufort Sea, the Arctic continental margins off the Canadian Arctic Archipelago and northern Greenland. This, the Worlds smallest ocean, is a virtually land-locked ocean that makes up merely 2.6 % of the area, and 1.0 % of the volume, of the entire World Ocean. The continental shelf area, from the coastline out to the shelf break, comprises as much as 52.9 % of the total area in the Arctic Ocean, which is significantly larger in comparison to the rest of the world oceans where the proportion of shelves, from the coastline out to the foot of the continental slope, only ranges between about 9.1 % and 17.7 %. In Jakobsson [2002], the seafloor area and water volume were calculated for different depths starting from the present sea level and progressing in increments of 10 m to a depth of 500 m, and in increments of 50 m from 550 m down to the deepest depth within each of the analyzed Arctic Ocean seas. Hypsometric curves expressed as simple histograms of the frequencies in different depth bins were presented, along with depth plotted against cumulative area for each of the analyzed seas. The derived hypsometric curves show that most of the Arctic Ocean shelf seas besides the Barents Sea, Beaufort Sea and the shelf off northern Greenland have a similar shape with the largest seafloor area between 0 and 50 m. The East Siberian and Laptev seas, in particular, show area distributions concentrated in this shallow depth range, and together with the Chukchi Sea they form a large flat shallow shelf province comprising as much as 22 Besides being the world’s smallest ocean with the by far largest shelf area in proportion to its size, the Arctic Ocean is unique in terms of its physiographic setting. The Fram Strait is the only real break in the barrier of vast continental shelves enclosing the Arctic Ocean. The second largest physiographic province after the continental shelves consists of ridges, which is in contrast to the rest of the World’s oceans where abyssal plains dominate. As much as 15.8 % of the area is underlain by ridges indicating the profound effect they have on ocean circulation

Database Analysis to Support Nutrient Criteria Development (Phase II)

The intent of this publication of the Arkansas Water Resources Center is to provide a location whereby a final report on water research to a funding agency can be archived. The Texas Commission on Environmental Quality (TCEQ) contracted with University of Arkansas researchers for a multiple year project titled “Database Analysis to Support Nutrient Criteria Development”. This publication covers the second of three phases of that project and has maintained the original format of the report as submitted to TCEQ. This report can be cited either as an AWRC publication (see below) or directly as the final report to TCEQ

Recent extensions to the free-vortex-sheet theory for expanded convergence capability

A new version of the free vortex sheet formulation is presented which has greatly improved convergence characteristics for a broad range of geometries. The enhanced convergence properties were achieved largely with extended modeling capabilities of the leading edge vortex and the near field trailing wake. Results from the new code, designated FVS-1, are presented for a variety of configurations and flow conditions with emphasis on vortex flap applications

Internships: Academic Learning Outcomes

Proponents of experiential learning have long recognized the learning benefits students can achieve through internships, service-learning experiences, and co-ops. There are others, however, who see those experiences as career exploration, good for the resume, but not integral to academic learning and so, not valid for the earning of academic credit. Even if internships are viewed as a valid component of the learning cycle (Kolb), what do we expect students to learn? How do we articulate outcomes that relate to a student\u27s discipline major or to a liberal arts curriculum? Finally, how can we assess whether a student is meeting the outcomes we identify

The lateral-directional characteristics of a 74-degree Delta wing employing gothic planform vortex flaps

The low speed lateral/directional characteristics of a generic 74 degree delta wing body configuration employing the latest generation, gothic planform vortex flaps was determined. Longitudinal effects are also presented. The data are compared with theoretical estimates from VORSTAB, an extension of the Quasi vortex lattice Method of Lan which empirically accounts for vortex breakdown effects in the calculation of longitudinal and lateral/directional aerodynamic characteristics. It is indicated that leading edge deflections of 30 and 40 degrees reduce the magnitude of the wing effective dihedral relative to the baseline for a specified angle of attack or lift coefficient. For angles of attack greater than 15 degrees, these flap deflections reduce the configuration directional stability despite improved vertical tail effectiveness. It is shown that asymmetric leading edge deflections are inferior to conventional ailerons in generating rolling moments. VORSTAB calculations provide coarse lateral/directional estimates at low to moderate angles of attack. The theory does not account for vortex flow induced, vertical tail effects

Database Analysis to Support Nutrient Criteria Development (Phase III)

The intent of this publication of the Arkansas Water Resources Center is to provide a location whereby a final report on water research to a funding agency can be archived. The Texas Commission on Environmental Quality (TCEQ) contracted with University of Arkansas researchers for a multiple year project titled “Database Analysis to Support Nutrient Criteria Development”. This publication covers the third of three phases of that project and has maintained the original format of the report as submitted to TCEQ. This report can be cited either as an AWRC publication (see below) or directly as the final report to TCEQ

Watershed prioritization to reduce nutrient export: A framework for the State of Arkansas based on ambient water quality monitoring data

The annual formation of the Northern Gulf of Mexico hypoxic zone is driven by nutrient loading from the Mississippi-Atchafalaya River Basin (MARB). Member States of The Mississippi River/Gulf of Mexico Hypoxia Task have developed statewide strategies to identify priorities and opportunities for nutrient export reduction in the MARB. In 2014, the State of Arkansas joined the Task Force and initiated an Arkansas Nutrient Reduction Strategy (ANRS), which currently prioritizes ten Hydrologic Unit Code 8 (HUC-8) watersheds (ANRD, 2014). These priority watersheds were not selected based on measured in-stream nutrient concentrations or trends, which impedes quantitative assessment, goal setting, and linking investments to nutrient reduction progress. The ANRS is currently under revision to address these concerns, and the goal of this project was to develop a prioritization framework for the State of Arkansas based on robust statistical analysis of extensive, statewide ambient water quality monitoring data sets

The journey and destination need to be intentional: Perceptions of success in community-academic research partnerships

Research partnerships between community members and academics are dynamic microsystems that aim to increase community wellbeing within complex environments. Efforts to improve health and social outcomes in communities are challenging in their own right, but even the most experienced researchers or engaged community members can have difficulty navigating the collaborative terrain of community-academic research partnerships. Proponents of participatory research models that engage community members as co-researchers are still examining how the collaborative process interacts with, and impacts, both short- and long-term outcomes. As a result, there has been a call for additional studies that employ qualitative and quantitative methods to contribute to a holistic understanding of this approach to research. This pilot study utilized the participatory tenets of co-researcher models to explore how members of community-academic research partnerships think about partnership processes and outcomes, including how they delineate between the two. Web-based concept mapping methodology was combined with individual interviews in an innovative mixed methods research study to further the field’s understanding of how community and academic members define partnership success and evaluate the impact of their work. Our findings suggest that in the early stages of a partnership members rely on informal and intuitive evaluation of success based on how the partnership is functioning. These partnership processes, which serve as intermediate outcomes, largely influence member engagement in the work, but partnerships are ultimately deemed successful if intended community-based research outcomes are achieved.Keywords: community-academic research partnerships, participatory research, concept mapping methodology, mixed methods, partnership process, outcomes  

Constituent Loads and Trends in the Upper Illinois River Watershed: A Nonpoint Source Management Program Priority Watershed

The Arkansas Department of Agriculture - Natural Resources Division (ANRD) has identified the Upper Illinois River Watershed (UIRW; 11110103), a hydrologic unit code (HUC) 8 watershed, located in Northwest Arkansas for prioritization by the Nonpoint Source (NPS) Management Program. URIW encompasses the Illinois River from its headwaters to the state line with Oklahoma and has been the subject of interstate disputes over water quality for decades. Nonpoint source pollution concerns in UIRW are excess nutrients from agriculture and sediment from changes in land use/land cover (LULC). Local, state, and national groups, including the NPS Source Management Program, have invested in education, best management practices, and streambank restoration in the UIRW. This watershed is also subject to regulation on the application of poultry litter as fertilizer and permitted limits on phosphorus discharge from point sources, such as municipal wastewater treatment plants (WWTP). Longterm water-quality monitoring data are necessary to identify whether these interventions are influencing water quality. The lag time before water-quality response can be considerable. Robust data are also needed to guide where additional resources should be targeted, or to identify potential emerging water quality concerns