Now showing items 1-20 of 6232

    • Effects of Reading Text While Driving: A Driving Simulator Study

      Prevedouros, Panos; Miah, M. Mintu; Nathanail, Eftihia (2020-02)
      Although 47 US states make the use of a mobile phone while driving illegal, many people use their phone for texting and other tasks while driving. This research project summarized the large literature on distracted driving and compared major outcomes with those of our study. We focused on distraction due to reading text because this activity is most common. For this research project, we collected simulator observations of 203 professional taxi drivers (175 male, and 28 female) working at the same Honolulu taxi company, using the mid-range driving simulator VS500M by Virage. After a familiarization period, drivers were asked to read realistic text content relating to passenger pick up displayed on a 7-inch tablet affixed to the dashboard. The experimental scenario was simulated on a two-lane rural highway having a speed limit of 60 mph and medium traffic. Drivers needed to follow the lead vehicle under regular and text-reading conditions. The large sample size of this study provided a strong statistical base for driving distraction investigation on a driving simulator. The comparison between regular and text-reading conditions revealed that the drivers significantly increased their headway (20.7%), lane deviations (354%), total time of driving blind (352%), maximum duration of driving blind (87.6% per glance), driving blind incidents (170%), driving blind distance (337%) and significantly decreased lane change frequency (35.1%). There was no significant effect on braking aggressiveness while reading text. The outcomes indicate that driving performance degrades significantly by reading text while driving. Additional analysis revealed that important predictors for maximum driving blind time changes are sociodemographic characteristics, such as age and race, and past behavior attributes.
    • Seismicity and Stresses in the Kantishna Seismic Cluster, Central Alaska

      Burris, Lea A. (2007-12)
      The Kantishna Cluster is an enigmatic and energetic cluster of earthquakes located in central Alaska, just to the northwest of Mt. McKinley/Denali and adjacent to the Denali Fault. The Kantishna Cluster has no visible fault traces, and is often speculated to have a connection to the Denali Fault. The Kantishna Cluster is located at a hub of tectonic activity including Bering Block rotation to the west, bookshelf faulting to the northeast, and rotation of southern Alaska due to Pacific plate convergence to the south. The intention of this study was to broaden the knowledge base about the Kantishna Cluster and use the Mw 7.9 Denali Fault earthquake to find a relationship between the cluster and the Denali Fault Zone. Rate calculations in conjunction with z- and b-value changes show that the Denali Fault earthquake had little influence on the seismicity of the Kantishna Cluster, with the exception being the southern most portion closest to the Denali Fault. The highly variable background rate of seismicity in the Kantishna Cluster makes seeing changes in the seismicity difficult. Stress tensor inversions suggest a change in the stresses in the Kantishna Cluster; however, triangle diagram comparisons show that the pattern of earthquake mechanism types did not change. Coulomb stress change calculations predict small changes that were not observed in the data. Double difference hypocentral relocations show that the cloud of earthquakes collapses down to several distinct features. Seismicity trends resolved from hypocentral relocations made it possible to infer fault planes or planar structures in the region. The newly uncovered structures are utilized in the formation of a model involving two wedges to describe the seismicity in the Kantishna Cluster. The two wedges are being “squeezed” in opposite directions accommodating for compression across the cluster due to Pacific plate convergence.
    • Data (Appendix) for Book Chapter 43: Citizen Science Experience in Lumbini/Nepali for Sarus Cranes and Lesser Adjudants (Storks) with Regmi and Huettmann 2020 Hindu Kush Himalaya: Watersheds Downhill, Springer

      Karmacharya, D.K.; Duwal, R.; Yadav, S.K. (4/2/2020)
      This dataset consist of an appendix of citizen science data for the Sarus Crane and Adjudant storks in Lumbini and Jagdishpur Reservoir, Nepal. It's a plain MS Excel sheet.
    • Data (Appendix) for Book Chapter 33: Persistent Langur (Semnopithecus) decline in Nepal with Regmi and Huettmann 2020 Hindu Kush Himalaya: Watersheds Downhill, Springer

      Ale, Purna Bahadur; Regmi, Ganga Ram; Huettmann, Falk (4/2/2020)
      This dataset consists of an appendix of a GIS map of langur sp information in Nepal. The datasets are locations, presences and absences from a value-added GBIF.org query, transect data by the authors and literature data Details are specified in the book chapter by Ale et al in Regmi and Huettmann 2020. This is the first and best compiled data for this species in Nepal and shows national declines with large conservation management implications.
    • Data (Appendix) for Book Chapter 25: Museum Data holdings and Libraries in Nepal and Hindu Kush Himalaya region with Regmi and Huettmann 2020 Hindu Kush Himalaya: Watersheds Downhill, Springer

      Huettmann, Falk (4/2/2020)
      This compiled dataset consists of a value-added analysed GBIF data set in the wider Hindu Kush-Himalaya (HKH) region. The original data source is from individual national contributors found in GBIF. Data are used here for research purposes for the wider HKH region watersheds and to show institutional spread and distribution. Some major outside museums internationally are mentioned too. The dataset consists of MS Excel sheets Methods and details are specified in the book chapter by Huettmann in Regmi and Huettmann 2020. This is the first and best compiled data for the study area and is to set a start of such views and investigations towards a better and more fair access to data, as part of a better and more democratic decision-making process.
    • Data (Appendix) for Book Chapter 22: Rapid Assessment of Urban Birds and GIS models of Kathmandu and Pokhara, Nepal with Regmi and Huettmann 2020 Hindu Kush Himalaya: Watersheds Downhill, Springer

      Hansen, Lindsay; Huettmann, Falk (4/2/2020)
      This compiled dataset consists of a field data from rapid assessment of common birds found in urban areas of Kathmandu and Pokhara, Nepal, Hindu Kush-Himalaya (HKH) region.The dataset consists of 31 bird and animal species from a detection survey of 2 transects and photos in MS Excel sheets. It is overlaid with Open Street GIS map predictors for the study areas, and model predicted with GIS. We used the following 6 layers:waterways, natural places, shop polygons, land use, roads and highways and computed proximities for each in GIS. Methods and details are specified in the book chapter by Huettmann in Regmi and Huettmann 2020. This is the first and best compiled field and GIS data for the study area and is to set a start of such views and investigations towards a better and more fair access to data, as part of a better and more democratic decision-making process. Here an example is presented using avian species and GIS habitat layers.
    • Data (Appendix) for Book Chapter 37: 'Road, Railroad and Airport data for the Hindu Kush Himalaya region' with Regmi and Huettmann 2020 Hindu Kush Himalaya: Watersheds Downhill, Springer

      Huettmann, Falk (4/2/2020)
      This compiled dataset consists of an appendix of value-added merged GIS maps for roads, railroads and airports in the wider Hindu Kush-Himalaya (HKH) region. The original data source is from individual national DIVA-GIS files and used here for research purposes for the wider HKH region watersheds. Nations included are: Nepal, India, China, Buthan, Kazachstan, Tajikistan, Kyrgystan, Uzbekistan, Turkmenistan, Afghanistan, Iran, Laos, Myanmar, Thailand, Vietnam, Pakistan, Bangladesh and Cambodia. The dataset consists of 21zip archives of these nations also covering railways and airports. Methods and details are specified in the book chapter by Huettmann in Regmi and Huettmann 2020. This is the first and best compiled data for the study area.
    • Data (Appendix) for Book Chapter 28: Sarus Crane GIS Model with Regmi and Huettmann 2020 Hindu Kush-Himalaya: Watersheds Downhill, Springer

      Karmacharya, D. K.; Huettmann, F.; Mi, C; Han, X; Duwal, R; Yadav, SK; Guo, Y (4/2/2020)
      This dataset consist of an appendix of GIS model predictions of Sarus Cranes (GRus antigone Taxonomic Serial Number TSN: 176181) in Nepal. Details are specified in the book chapter by Karmacharya et al in G.R.Regmi and F. Huettmann 2020. This is the first model for this species and shows conservation management implications for the Terai landscape between Nepal and India.
    • Two Years of High-Resolution Airborne Imagery and Value-Added Products for the Barrow Environmental Observatory

      Cherry, Jessica; Lovick, Joe; Crowder, Kerri; Cunningham, Keith; Schroder, Julien (2013-12)
      Optical and thermal infrared imagery were collected by UAF at the Arctic NGEE Intensive sites in 2012 and 2013.
    • Science Plan for Regional Arctic System Modeling

      Roberts, Andrew (2010-11-01)
      Data and PDFs for "A Science Plan for Regional Arctic System Modeling" by Roberts, A. and Coauthors, 2010, IARC Technical Report 10-0001. The data collection includes the full report, a NetCDF file containing information used to illustrate and define the Arctic System in Figure 2, and supplemental PDFs of individual figures produced especially for the report. A URL is also provided that links to workshops where outcomes contributed substantially to this report. The purpose of the science plan is to provide a roadmap for understanding variability, complexity and change in the Arctic and it's adjacent environments, including understanding interconnectivity of the geosphere, biosphere and anthroposphere of the high north.
    • Final Report: International Workshop to Reconcile Methane Budgets in the Northern Permafrost Region

      McGuire, A. David; Kelly, Brendan P.; Guy, Lisa Sheffield; Wiggins, Helen (2017-05-18)
      An International Workshop to Reconcile Methane Budgets in the Northern Permafrost Region, organized by the Study of Environmental Arctic Change (SEARCH), was held in Seattle on 7-9 March 2017. The workshop was funded by the National Science Foundation, the National Aeronautics and Space Administration, the U.S. Geological Survey, and the U.S. Arctic Research Commission. The primary goal was to produce a plan for reconciling methane budgets in the northern permafrost region. Forty-two scientists, including representatives of the atmospheric, inland (wetland and lakes), marine (coastal and oceanic), and remote sensing communities studying methane dynamics participated in developing the research plan. Eleven of the participants were early career scientists, and nine of the scientists were from institutions outside the United States. The first day of the workshop included keynote presentations that provided atmospheric, inland, and marine perspectives on developing a plan to reconcile methane budgets. There were also keynote presentations on the role of remote sensing in reconciling methane budgets. The second day of the workshop was devoted to breakout groups that developed plans from disciplinary perspectives, followed by breakouts of mixed disciplinary groups that discussed all three plans. The breakout groups identified key uncertainties and near-term and longer-term priorities for addressing questions about methane dynamics in the northern permafrost region. Participants committed to completing a paper describing a roadmap for the synthesis plan by the end of 2017, and each of the groups developed plans to address, by the end of 2018, near-term priorities to reduce uncertainties in methane budgets. The longer-term priorities include addressing possible sensitivities of methane emissions to climate variability and change in the region and evaluating the degree to which changes in methane dynamics are detectable. To address these longer-term priorities, there is a need to organize extant methane data for the northern permafrost region so that studies using these data can evaluate how enhancements to the methane observation network would improve estimates of methane emissions and the detection of trends. The Permafrost Action Team of SEARCH will develop research summaries and briefs based on the follow-on activities from the workshop.
    • Operational Safety of Gravel Roads in Rural and Tribal Communities: Vulnerability to Structural Failures and GeoHazards

      Ibrahim, Ahmed; Sharma, Sunil; Kassem, Emad; Nielsen, Richard; Nasrin, Sabreena (2020-04-20)
      Of the 4.1 million miles of federal and state highways in the U.S., 2.2 million miles (or 54%) are unpaved, gravel roads. In the Pacific Northwest and Alaska, unpaved gravel roads provide critical transportation access, with some communities relying on just a single highway for access into and out of town. In such cases, these highways become a critical component of the infrastructure, and there is a need to ensure that safe access is always available to the communities. The Idaho highway database has been used to identify unpaved, gravel roads in Idaho that are critical for access to rural communities. Once identified, information regarding their existing condition has been used to assess their vulnerability and other impacts. The results of this study are considered an initial evaluation that relies on information that is readily available in the database. The project outcomes include a comprehensive literature review of unpaved roads including data produced from field visits. In addition, a questionnaire survey was sent to local jurisdictions authorities for investigating locations, reasons of road closures, and population size of the affected communities. Finally, 37 responses have been received by the research team indicating five rural communities that have experienced closures and isolation. The reasons for the closure of the unpaved roads were due to the lack of funding for snow removal, excessive dirt, unstable gravel roads, tornados, and heavy rains. The location of those communities was spread across the state of Idaho with corresponding populations range from 25 to 8,500 people.
    • Recent and Possible Future Changes in Permafrost

      Romanovsky, Vladimir (2013-10)
      Recent observations indicate a warming of permafrost in many northern regions with the resulting degradation of ice-rich and carbon rich permafrost. Permafrost temperature has increased by 0.5°C to 3°C in the northern Hemisphere during the last 30-40 years (Romanovsky et al., 2010).
    • Conceptualization and Application of Arctic Tundra Landscape Evolution Using the Alaska Thermokarst Model

      Bolton, W. Robert; Romanovsky, Vladimir; McGuire, A. David; Lara, Mark (2015-05)
      Thermokarst topography forms whenever ice-rich permafrost thaws and the ground subsides due to the volume loss when excess ice transitions to water. The Alaska Thermokarst Model (ATM) is a large-scale, state-and-transition model designed to simulate transitions between [non-]thermokarst landscape units, or cohorts. The ATM uses a frame-based methodology to track transitions and proportion of cohorts within a 1- km2 grid cell. In the arctic tundra environment, the ATM tracks thermokarst related transitions between wetland tundra, graminoid tundra, shrub tundra, and thermokarst lakes. The transition from one cohort to another due to thermokarst processes can take place if seasonal thaw of the ground reaches ice-rich soil layers either due to pulse disturbance events such as a large precipitation event, wildfire, or due to gradual active layer deepening that eventually reaches ice-rich soil. The protective layer is the distance between the ground surface and ice-rich soil. The protective layer buffers the ice-rich soils from energy processes that take place at the ground surface and is critical to determining how susceptible an area is to thermokarst degradation. The rate of terrain transition in our model is determined by the soil ice-content, the drainage efficiency (or ability of the landscape to store or transport water), and the probability of thermokarst initiation. Tundra types are allowed to transition from one type to another (i.e. a wetland tundra to a graminoid tundra) under favorable climatic conditions. In this study, we present our conceptualization and initial simulation results of the ATM for an 1792 km2 area on the Barrow Peninsula, Alaska. The area selected for simulation is located in a polygonal tundra landscape under varying degrees of thermokarst degradation. The goal of this modeling study is to simulate landscape evolution in response to thermokarst disturbance as a result of climate change.
    • Climate Divisions for Alaska Based on Objective Methods

      Bieniek, Peter A.; Bhatt, Uma S.; Thoman, Richard L.; Angeloff, Heather; Partain, James; Papineau, John; Fritsch, Frederick; Holloway, Eric; Walsh, John E.; Daly, Chris; et al. (2012-12)
      Alaska climate regions first drawn by Fitton (1930) [Fitton]. Divisions outlined by Searby (1968) currently used by the National Climatic Data Center [NCDC]. Climate regions updated by Shulski and Wendler (2007) [ACRC]. None are based on primarily objective methods. Useful for seasonal forecasting and many other research applications.
    • 2016 Snow Melt in the NGEE-Arctic Teller Research Watershed

      Busey, Robert; Wilson, Cathy; Iwahana, Go; Bolton, W. Robert; Cohen, Lily (2016-12)
      In April 2016, daily transects were made across the Teller Road Basin to begin the several year process of characterizing the largest event in the northern hydrologic year: snow melt. This year was an experiment to see how much could be accomplished (a full suite of time intensive measurements) during this interval.
    • Uncertainties in Arctic Precipitation

      Majhi, Ipshita; Alexeev, Vladimir; Cherry, Jessica; Groisman, Pavel; Cohen, Judah (2012-12)
      It is crucial to measure precipitation accurately to predict future water budget with confidence. In our study, we aim to understand and compare precipitation datasets and discrepancies associated with them. We divide our datasets into three classes-raw data (data that have only been preprocessed to minimum quality control);corrected products (data that have been adjusted by their respective authors); finally, a reanalysis dataset (a combination of observed data and model output).
    • Scenarios to prioritize observing activities on the North Slope, AK

      Lee, Olivia; Lassuy, Dennis; Payne, John; Vargas, Juan Carlos; Eicken, Hajo (2016-03)
      The North Slope of Alaska is experiencing rapid changes in response to interacting climate and socioeconomic drivers. The North Slope Science Initiative (NSSI) is using scenarios as a tool to identify plausible, spatially explicit future states of resource extraction activities on the North Slope and adjacent seas through the year 2040. The objective of the scenarios process is to strategically assess research and monitoring needs on the North Slope. The participatory scenarios process involved stakeholder input (including Federal, State, local, academic, industry and non-profit representatives) to identify key drivers of change related to resource extraction activities on the North Slope. While climate change was identified as a key driver in the biophysical system, economic drivers related to oil and gas development were also important. Expert-reviewed informational materials were developed to help stakeholders obtain baseline knowledge and stimulate discussions about interactions between drivers, knowledge gaps and uncertainties. Map-based scenario products will allow mission-oriented agencies to jointly explore where to prioritize research investments and address risk in a complex, changing environment. Scenarios consider multidecadal timescales. However, tracking of indicator variables derived from scenarios can lead to important insights about the trajectory of the North Slope social-environmental system and inform management decisions to reduce risk on much shorter timescales. The inclusion of stakeholders helps provide a broad spectrum of expert viewpoints necessary for considering the range of plausible scenarios.
    • Scenarios in Social-Ecological Systems: Co-Producing Futures in Arctic Alaska

      Lovecraft, A. L.; Eicken, H. (2016-12)
      Scenarios are used to think ahead in rapidly changing, complex, and competitive environments, and make crucial decisions in absence of complete information about the future. Currently, at many regional scales of governance, there is a growing need for legitimate tools that enable the actors (e.g., governments, corporations, organized interests) at local-scales to address pressing concerns in the midst of uncertainty. This is particularly true of areas experiencing rapidly changing environments (e.g., drought, floods, diminishing sea ice, erosion) and complex social problems (e.g., remote communities, resource extraction, threatened cultures). Scenario exercises produce neither forecasts of what is to come nor are they visions of what participants would like to happen. Rather, they produce pertinent evidence-based information related to questions of “what would happen if...” and thus provide the possibility of strategic decision- making to plan research that promotes community resilience.