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• 611. [Article] Climate Change Impact on the Spatio-Temporal Variability of Hydro-Climate Extremes

  The rising temperature of the earth due to climate change has shown to alter the variations of hydro-climate variables, including their intensities, frequencies and durations. Extreme events such as floods ...

  Citation × Citation Citation Abstract Copy Title: Climate Change Impact on the Spatio-Temporal Variability of Hydro-Climate Extremes Author: Najafi, Mohammad Reza Year: 2013 The rising temperature of the earth due to climate change has shown to alter the variations of hydro-climate variables, including their intensities, frequencies and durations. Extreme events such as floods are, in particular, susceptible to any disturbances in climate cycles. As such it is important to provide policymakers with sufficient knowledge about the probable impacts of climate change on hydrologic extremes and most importantly on floods, which have the highest impacts on the societies. For this reason analysis of hydro-climate extremes is commonly performed using data at each site (or grid cell), however due to the limited number of extreme events, these analyses are not robust. Current methods, such as the regional frequency analysis, which combine data from different locations are incapable of incorporating the spatial structure of the data as well as other explanatory variables, and do not explicitly, assess the uncertainties. In this thesis the spatial hierarchical Bayesian model is proposed for hydro-climate extreme analyses using data recorded at each site or grid. This method combines limited number of data from different locations, estimates the uncertainties in different stages of the hierarchy, incorporates additional explanatory variables (covariates), and can be used to estimate extreme events at un-gaged sites. The first project develops a spatial hierarchical Bayesian method to model the extreme runoffs over two spatial domains in the Columbia River Basin, U.S. The model is also employed to estimate floods with different return levels within time slices of fifteen years in order to detect possible trends in runoff extremes. Continuing on the extreme analysis, the impact of climate change on runoff extremes is investigated over the whole Pacific Northwest (PNW). This study aims to address the question of how the runoff extremes will change in the future compared to the historical time period, investigate the different behaviors of the regional climate models (RCMs) regarding the runoff extremes, and assess the seasonal variations of runoff extremes. Given the increasing number of climate model simulations the goal of the third project is to provide a multi-model ensemble average of hydro-climate extremes and characterize the inherent uncertainties. Outputs from several regional climate models provided by NARCCAP are considered for the analysis in all seasons. Three combination scenarios are defined and compared for multi-modeling of extreme runoffs. The biases of each scenario are calculated and the scenario with the least bias is selected for projecting seasonal runoff extremes. The aim of the fourth project is to quantify and compare the uncertainties regarding global climate models to the ones from the hydrologic model structures in climate change impact studies. Various methods have been proposed to downscale the coarse resolution General Circulation Model (GCM) climatological variables to the fine scale regional variables; however fewer studies have been focused on the selection of GCM predictors. Additionally, the results obtained from one downscaling technique may not be robust and the uncertainties related to the downscaling scheme are not realized. To address these issues, in the fifth study we employed Independent Component Analysis (ICA) for predictor selection which determines spatially independent GCM variables (as discussed in Appendix A). Cross validation of the independent components is employed to find the predictor combination that describes the regional precipitation over the upper Willamette basin with minimum error. These climate variables along with the observed precipitation are used to calibrate three downscaling models: Multi Linear Regression (MLR), Support Vector Machine (SVM) and Adaptive-Network-Based Fuzzy Inference System (ANFIS). Title: Climate Change Impact on the Spatio-Temporal Variability of Hydro-Climate Extremes Author: Najafi, Mohammad Reza Year: 2013 The rising temperature of the earth due to climate change has shown to alter the variations of hydro-climate variables, including their intensities, frequencies and durations. Extreme events such as floods are, in particular, susceptible to any disturbances in climate cycles. As such it is important to provide policymakers with sufficient knowledge about the probable impacts of climate change on hydrologic extremes and most importantly on floods, which have the highest impacts on the societies. For this reason analysis of hydro-climate extremes is commonly performed using data at each site (or grid cell), however due to the limited number of extreme events, these analyses are not robust. Current methods, such as the regional frequency analysis, which combine data from different locations are incapable of incorporating the spatial structure of the data as well as other explanatory variables, and do not explicitly, assess the uncertainties. In this thesis the spatial hierarchical Bayesian model is proposed for hydro-climate extreme analyses using data recorded at each site or grid. This method combines limited number of data from different locations, estimates the uncertainties in different stages of the hierarchy, incorporates additional explanatory variables (covariates), and can be used to estimate extreme events at un-gaged sites. The first project develops a spatial hierarchical Bayesian method to model the extreme runoffs over two spatial domains in the Columbia River Basin, U.S. The model is also employed to estimate floods with different return levels within time slices of fifteen years in order to detect possible trends in runoff extremes. Continuing on the extreme analysis, the impact of climate change on runoff extremes is investigated over the whole Pacific Northwest (PNW). This study aims to address the question of how the runoff extremes will change in the future compared to the historical time period, investigate the different behaviors of the regional climate models (RCMs) regarding the runoff extremes, and assess the seasonal variations of runoff extremes. Given the increasing number of climate model simulations the goal of the third project is to provide a multi-model ensemble average of hydro-climate extremes and characterize the inherent uncertainties. Outputs from several regional climate models provided by NARCCAP are considered for the analysis in all seasons. Three combination scenarios are defined and compared for multi-modeling of extreme runoffs. The biases of each scenario are calculated and the scenario with the least bias is selected for projecting seasonal runoff extremes. The aim of the fourth project is to quantify and compare the uncertainties regarding global climate models to the ones from the hydrologic model structures in climate change impact studies. Various methods have been proposed to downscale the coarse resolution General Circulation Model (GCM) climatological variables to the fine scale regional variables; however fewer studies have been focused on the selection of GCM predictors. Additionally, the results obtained from one downscaling technique may not be robust and the uncertainties related to the downscaling scheme are not realized. To address these issues, in the fifth study we employed Independent Component Analysis (ICA) for predictor selection which determines spatially independent GCM variables (as discussed in Appendix A). Cross validation of the independent components is employed to find the predictor combination that describes the regional precipitation over the upper Willamette basin with minimum error. These climate variables along with the observed precipitation are used to calibrate three downscaling models: Multi Linear Regression (MLR), Support Vector Machine (SVM) and Adaptive-Network-Based Fuzzy Inference System (ANFIS). Close

• 612. [Article] An empirical study of the effect of systematic relaxation training of chronically-anxious subjects on the communication variable of closed-mindedness

  This is a study of whether an attempt to reduce the trait of high tension-anxiety by means of systematic neuro-musculature relaxation training will result in a decrease of the communication variable of ...

  Citation × Citation Citation Abstract Copy Title: An empirical study of the effect of systematic relaxation training of chronically-anxious subjects on the communication variable of closed-mindedness Author: Barna, La Ray Year: 1970 This is a study of whether an attempt to reduce the trait of high tension-anxiety by means of systematic neuro-musculature relaxation training will result in a decrease of the communication variable of closed-mindedness. A general review of the literature showed that the problem of tension-anxiety is complex, pervasive, and detrimental to effective communication. First, an attempt is made to bring relevant information to the field of general speech by citing a few findings from the research of other disciplines concerning the nature and effects of tension-anxiety. Currently-used methods of anxiety reduction are mentioned, and one, neuro-musculature relaxation training, discussed as to its effectiveness and adaptability to the college environment. This method was chosen for investigation in the present study because it can be administered to groups by trained personnel, who need not be professional psychotherapists, at no risk to the students. The major hypothesis is that there will be a significant difference between the dogmatism scores of the experimental group who receive relaxation training and the dogmatism scores of the control group who did not receive such training. The minor hypothesis is that there will be a significantly greater difference between the pre- and post-anxiety scores of the experimental group than between the pre-and post-anxiety scores of the control group, and the post-scores will show a downward trend. The design of the study consisted first of selecting a group of high-anxious subjects by administering the Taylor Manifest Anxiety Scale to all students who enrolled in the beginning fundamental speech course, which totaled 427, and sending invitations to the fifty-six students who scored twenty-four and above to participate in the research study. Those who accepted were arbitrarily placed in either the control group or the experimental group depending on whether their time schedules permitted them to attend the previously-scheduled training meetings. The experimental group was given a series of six weekly training sessions of forty-five minutes each using a modified version of the Jacobson method of progressive neuro-musculature relaxation. There was no more contact with the control group until after the six-week period when both groups were administered the Rokeach Dogmatism Scale and a repeat of the Manifest Anxiety Scale. Statistical procedures were employed at this time, and since no significant differences were found both hypotheses were rejected. The findings of this study show that the method of systematic neuro-musculature relaxation training employed did not cause significant differences in either the dogmatism or the chronic tension-anxiety level of the experimental subjects according to the measuring devices used. That the method could be used with the equipment and conditions of a normal college environment and with trained non-professionals as therapists was evident. Whether it would be useful for the reduction of chronic high tension-anxiety remains in doubt due to the uncertain motivation of the experimental subjects and the questionable sensitivity of the Manifest Anxiety Scale as a measurement of tension-anxiety change. Further study using a combination of measuring devices, including the electromyograph, is recommended. Title: An empirical study of the effect of systematic relaxation training of chronically-anxious subjects on the communication variable of closed-mindedness Author: Barna, La Ray Year: 1970 This is a study of whether an attempt to reduce the trait of high tension-anxiety by means of systematic neuro-musculature relaxation training will result in a decrease of the communication variable of closed-mindedness. A general review of the literature showed that the problem of tension-anxiety is complex, pervasive, and detrimental to effective communication. First, an attempt is made to bring relevant information to the field of general speech by citing a few findings from the research of other disciplines concerning the nature and effects of tension-anxiety. Currently-used methods of anxiety reduction are mentioned, and one, neuro-musculature relaxation training, discussed as to its effectiveness and adaptability to the college environment. This method was chosen for investigation in the present study because it can be administered to groups by trained personnel, who need not be professional psychotherapists, at no risk to the students. The major hypothesis is that there will be a significant difference between the dogmatism scores of the experimental group who receive relaxation training and the dogmatism scores of the control group who did not receive such training. The minor hypothesis is that there will be a significantly greater difference between the pre- and post-anxiety scores of the experimental group than between the pre-and post-anxiety scores of the control group, and the post-scores will show a downward trend. The design of the study consisted first of selecting a group of high-anxious subjects by administering the Taylor Manifest Anxiety Scale to all students who enrolled in the beginning fundamental speech course, which totaled 427, and sending invitations to the fifty-six students who scored twenty-four and above to participate in the research study. Those who accepted were arbitrarily placed in either the control group or the experimental group depending on whether their time schedules permitted them to attend the previously-scheduled training meetings. The experimental group was given a series of six weekly training sessions of forty-five minutes each using a modified version of the Jacobson method of progressive neuro-musculature relaxation. There was no more contact with the control group until after the six-week period when both groups were administered the Rokeach Dogmatism Scale and a repeat of the Manifest Anxiety Scale. Statistical procedures were employed at this time, and since no significant differences were found both hypotheses were rejected. The findings of this study show that the method of systematic neuro-musculature relaxation training employed did not cause significant differences in either the dogmatism or the chronic tension-anxiety level of the experimental subjects according to the measuring devices used. That the method could be used with the equipment and conditions of a normal college environment and with trained non-professionals as therapists was evident. Whether it would be useful for the reduction of chronic high tension-anxiety remains in doubt due to the uncertain motivation of the experimental subjects and the questionable sensitivity of the Manifest Anxiety Scale as a measurement of tension-anxiety change. Further study using a combination of measuring devices, including the electromyograph, is recommended. Close

• 613. [Article] Relational Database Analysis of Dated Prehistoric Shorelines to Establish Sand Partitioning in Late Holocene Barriers and Beach Plains of the Columbia River Littoral Cell, Washington and Oregon, USA

  Studies of episodic shoreline accretion of the Columbia River Littoral Cell (CRLC) have been ongoing since 1964. In this study, the sediment volumes in the late Holocene barriers and beach plains are compiled ...

  Citation × Citation Citation Abstract Copy Title: Relational Database Analysis of Dated Prehistoric Shorelines to Establish Sand Partitioning in Late Holocene Barriers and Beach Plains of the Columbia River Littoral Cell, Washington and Oregon, USA Author: Linde, Tamara Causer Year: 2014 Studies of episodic shoreline accretion of the Columbia River Littoral Cell (CRLC) have been ongoing since 1964. In this study, the sediment volumes in the late Holocene barriers and beach plains are compiled and formatted in GIS compatible databases for the four sub-cells of the CRLC. Initial evaluation involved the creation of a geodatabase of 160 dated retreat scarp positions, that were identified on across-shore GPR and borehole profiles. Ten primary timelines were identified throughout the CRLC (0-4700 ybp) and those were used to develop polygon cells. Elevation, distance measurements, and position information were all linked to the polygon through a centroid location within the geodatabase. Once the geodatabase was completed, data was imported into MSAccessTM to create a relational database that would allow for examination of the littoral cell in its entirety or of the individual sub-cells. Within the database, sediment volumes, ages, accretion rates, sediment thicknesses, and timeline relationships were calculated and recorded. Using the database, the accretion history of the Columbia River Littoral Cell was evaluated and this examination illustrated the complexity of the system. Northern littoral transport was shown to be an important factor in the development of the littoral cell as a whole. Total sediment volume in the littoral cell was calculated to be 1.74 x 109 m3, with a mean accretion rate of 1.90 x 104 m3/yr, which is significantly less than some previous studies. This is due to a more detailed analysis of the beach and foredune facies themselves. This is likely the result of the higher precision of beach and foredune surface information using LiDAR. The database shows that the developmental history of the CRLC is dependent on temporal and spatial constraints that can be coupled with reverse modeling to predict shoreline erosion trends from impounded river sediments and potential global sea level rise. The North Beaches and Grayland Plains sub-cells have the greatest potential for future erosion; followed by the Clatsop Plains sub-cell. Title: Relational Database Analysis of Dated Prehistoric Shorelines to Establish Sand Partitioning in Late Holocene Barriers and Beach Plains of the Columbia River Littoral Cell, Washington and Oregon, USA Author: Linde, Tamara Causer Year: 2014 Studies of episodic shoreline accretion of the Columbia River Littoral Cell (CRLC) have been ongoing since 1964. In this study, the sediment volumes in the late Holocene barriers and beach plains are compiled and formatted in GIS compatible databases for the four sub-cells of the CRLC. Initial evaluation involved the creation of a geodatabase of 160 dated retreat scarp positions, that were identified on across-shore GPR and borehole profiles. Ten primary timelines were identified throughout the CRLC (0-4700 ybp) and those were used to develop polygon cells. Elevation, distance measurements, and position information were all linked to the polygon through a centroid location within the geodatabase. Once the geodatabase was completed, data was imported into MSAccessTM to create a relational database that would allow for examination of the littoral cell in its entirety or of the individual sub-cells. Within the database, sediment volumes, ages, accretion rates, sediment thicknesses, and timeline relationships were calculated and recorded. Using the database, the accretion history of the Columbia River Littoral Cell was evaluated and this examination illustrated the complexity of the system. Northern littoral transport was shown to be an important factor in the development of the littoral cell as a whole. Total sediment volume in the littoral cell was calculated to be 1.74 x 109 m3, with a mean accretion rate of 1.90 x 104 m3/yr, which is significantly less than some previous studies. This is due to a more detailed analysis of the beach and foredune facies themselves. This is likely the result of the higher precision of beach and foredune surface information using LiDAR. The database shows that the developmental history of the CRLC is dependent on temporal and spatial constraints that can be coupled with reverse modeling to predict shoreline erosion trends from impounded river sediments and potential global sea level rise. The North Beaches and Grayland Plains sub-cells have the greatest potential for future erosion; followed by the Clatsop Plains sub-cell. Close

• 614. [Article] Investigating the Impact of Sibling Foster Care on Placement Stability

  Sibling relationships are an important, yet under investigated aspect of foster care research. Despite the fact that between 65-85% of children in care have brothers and sisters, only recently have child ...

  Citation × Citation Citation Abstract Copy Title: Investigating the Impact of Sibling Foster Care on Placement Stability Author: Waid, Jeffrey David Year: 2015 Sibling relationships are an important, yet under investigated aspect of foster care research. Despite the fact that between 65-85% of children in care have brothers and sisters, only recently have child welfare researchers begun to explore the complex and dynamic nature of sibling relationships in substitute care settings. Although cross-sectional and longitudinal studies suggest differences in placement stability and permanency outcomes for siblings placed together versus those placed separately, the conditions under which sibling relationships influence placement stability, permanency, and well-being in foster care settings remain unknown. This dissertation investigated how family dynamics and home setting characteristics influenced the likelihood of a foster care placement change for a sample of children who participated in a sibling relationship enhancement intervention (SIBS-FC) study. A conceptual model was proposed to help explain the circumstances which lead to foster care placement change, and the moderating effects of family living composition on the odds of placement change over an 18-month period were examined. Two multivariate statistical approaches were used in this investigation. The first approach involved examining the effects of a child's report of positive home integration, sibling relationship quality, caregiver's reported impact of child behavior, sibling living situation, kinship caregiver status, number of placements prior to study entry, and receipt of the SIBS-FC intervention on the odds of placement change. Results suggest that children in kinship care were 58% less likely to experience placement change than those who lived in non-relative care, and youth who lived apart from their siblings were 70% more likely to experience placement change than those who lived together. In the second statistical approach, living composition categories were constructed to understand the moderating effects of different living situations on the odds of placement change. Living composition categories included youth who lived in kinship care with their siblings, youth who lived in kinship care without their siblings, and youth who lived in non-relative care with their siblings, with youth in non-relative care who lived apart from their siblings serving as the referent category. Findings support a moderation effect for different categories of living composition, as well as a trend level effect for sibling relationship quality and odds of placement change. Living with one's sibling in kinship care decreased the odds of placement change by 75%, as compared to living apart from one's sibling in a non-relative foster home. A post-hoc analysis determined that all living composition categories were statistically different from one another in relative odds of a placement change. This dissertation provides additional evidence concerning the protective nature of kinship care and sibling co-placement on reducing the odds of experiencing a foster care placement change, and provides support for practices and policies prioritizing kinship care and the co-placement of siblings when making substitute care placement decisions. Future studies of siblings in foster care should explore the experiences of youth across the different forms of foster care living composition, examine the relationship between placement stability and permanency outcomes, and examine the relationship between placement stability, permanency, and child well-being. Title: Investigating the Impact of Sibling Foster Care on Placement Stability Author: Waid, Jeffrey David Year: 2015 Sibling relationships are an important, yet under investigated aspect of foster care research. Despite the fact that between 65-85% of children in care have brothers and sisters, only recently have child welfare researchers begun to explore the complex and dynamic nature of sibling relationships in substitute care settings. Although cross-sectional and longitudinal studies suggest differences in placement stability and permanency outcomes for siblings placed together versus those placed separately, the conditions under which sibling relationships influence placement stability, permanency, and well-being in foster care settings remain unknown. This dissertation investigated how family dynamics and home setting characteristics influenced the likelihood of a foster care placement change for a sample of children who participated in a sibling relationship enhancement intervention (SIBS-FC) study. A conceptual model was proposed to help explain the circumstances which lead to foster care placement change, and the moderating effects of family living composition on the odds of placement change over an 18-month period were examined. Two multivariate statistical approaches were used in this investigation. The first approach involved examining the effects of a child's report of positive home integration, sibling relationship quality, caregiver's reported impact of child behavior, sibling living situation, kinship caregiver status, number of placements prior to study entry, and receipt of the SIBS-FC intervention on the odds of placement change. Results suggest that children in kinship care were 58% less likely to experience placement change than those who lived in non-relative care, and youth who lived apart from their siblings were 70% more likely to experience placement change than those who lived together. In the second statistical approach, living composition categories were constructed to understand the moderating effects of different living situations on the odds of placement change. Living composition categories included youth who lived in kinship care with their siblings, youth who lived in kinship care without their siblings, and youth who lived in non-relative care with their siblings, with youth in non-relative care who lived apart from their siblings serving as the referent category. Findings support a moderation effect for different categories of living composition, as well as a trend level effect for sibling relationship quality and odds of placement change. Living with one's sibling in kinship care decreased the odds of placement change by 75%, as compared to living apart from one's sibling in a non-relative foster home. A post-hoc analysis determined that all living composition categories were statistically different from one another in relative odds of a placement change. This dissertation provides additional evidence concerning the protective nature of kinship care and sibling co-placement on reducing the odds of experiencing a foster care placement change, and provides support for practices and policies prioritizing kinship care and the co-placement of siblings when making substitute care placement decisions. Future studies of siblings in foster care should explore the experiences of youth across the different forms of foster care living composition, examine the relationship between placement stability and permanency outcomes, and examine the relationship between placement stability, permanency, and child well-being. Close

• 615. [Article] An Investigation of Urban Mobile Source Aerosol Using Optical Properties Measured by CRDT/N: Diesel Particulate Matter and the Impact of Biodiesel

  Mobile source emissions are a major contributor to global and local air pollution. Governments and regulatory agencies have been increasing the stringency of regulations in the transportation sector for ...

  Citation × Citation Citation Abstract Copy Title: An Investigation of Urban Mobile Source Aerosol Using Optical Properties Measured by CRDT/N: Diesel Particulate Matter and the Impact of Biodiesel Author: Wright, Monica Elizabeth Year: 2012 Mobile source emissions are a major contributor to global and local air pollution. Governments and regulatory agencies have been increasing the stringency of regulations in the transportation sector for the last ten years to help curb transportation sector air pollution. The need for regulations has been emphasized by scientific research on the impacts from ambient pollution, especially research on the effect of particulate matter on human health. The particulate emissions from diesel vehicles, diesel particulate matter (DPM) is considered a known or probable carcinogen in various countries and increased exposure to DPM is linked to increased cardiovascular health problems in humans. The toxicity of vehicle emissions and diesel particulate emissions in particular, in conjunction with an increased awareness of potential petroleum fuel shortages, international conflict over petroleum fuel sources and climate change science, have all contributed to the increase of biodiesel use as an additive to or replacement for petroleum fuel. The goal of this research is to determine how this increased use of biodiesel in the particular emission testing setup impacts urban air quality. To determine if biodiesel use contributes to a health or climate benefit, both the size range and general composition were investigated using a comprehensive comparison of the particulate component of the emissions in real time. The emissions from various biodiesel and diesel mixtures from a common diesel passenger vehicle were measured with a cavity ring-down transmissometer (CRDT) coupled with a condensation particle counter, a SMPS, a nephelometer, NOx, CO, CO2, and O3 measurements. From these data, key emission factors for several biodiesel and diesel fuel mixtures were developed. This approach reduces sampling artifacts and allows for the determination of optical properties, particle number concentration, and size distributions, along with several important gas phase species' concentrations. Findings indicate that biodiesel additions to diesel fuel do not necessarily have an air quality benefit for particulate emissions in this emission testing scenario. The often cited linear decrease in particulate emissions with increasing biodiesel content was not observed. Mixtures with half diesel and half biodiesel tended to have the highest particulate emissions in all size ranges. Mixtures with more than 50% biodiesel had slightly lower calculated mass for light absorbing carbon, but this reduction in mass is most likely a result of a shift in the size of the emission particles to a smaller size range, not a reduction in the total number of particles. Evaluation of the extensive optical properties from this experimental set-up indicates that biodiesel additions to diesel fuel has an impact on emission particle extinction in both visible and near-IR wavelengths. The B99 mixture had the smallest emission factor for extinction at 532 nm and at 1064 nm. For the extinction at 532 nm, the trend was not linear and the emission factor peaked at the B50 mixture. Results from intensive properties indicate that emissions from B5 and B25 mixtures have Ångström exponents close to 1, typical for black carbon emissions. The mixtures with a larger fraction of biodiesel have Ångström exponent values closer to 2, indicating more absorbing organic matter and/or smaller particle size in the emissions. Additional experimental testing should be completed to determine the application of these results and emission factors to other diesel vehicles or types of diesel and biodiesel fuel mixtures. Title: An Investigation of Urban Mobile Source Aerosol Using Optical Properties Measured by CRDT/N: Diesel Particulate Matter and the Impact of Biodiesel Author: Wright, Monica Elizabeth Year: 2012 Mobile source emissions are a major contributor to global and local air pollution. Governments and regulatory agencies have been increasing the stringency of regulations in the transportation sector for the last ten years to help curb transportation sector air pollution. The need for regulations has been emphasized by scientific research on the impacts from ambient pollution, especially research on the effect of particulate matter on human health. The particulate emissions from diesel vehicles, diesel particulate matter (DPM) is considered a known or probable carcinogen in various countries and increased exposure to DPM is linked to increased cardiovascular health problems in humans. The toxicity of vehicle emissions and diesel particulate emissions in particular, in conjunction with an increased awareness of potential petroleum fuel shortages, international conflict over petroleum fuel sources and climate change science, have all contributed to the increase of biodiesel use as an additive to or replacement for petroleum fuel. The goal of this research is to determine how this increased use of biodiesel in the particular emission testing setup impacts urban air quality. To determine if biodiesel use contributes to a health or climate benefit, both the size range and general composition were investigated using a comprehensive comparison of the particulate component of the emissions in real time. The emissions from various biodiesel and diesel mixtures from a common diesel passenger vehicle were measured with a cavity ring-down transmissometer (CRDT) coupled with a condensation particle counter, a SMPS, a nephelometer, NOx, CO, CO2, and O3 measurements. From these data, key emission factors for several biodiesel and diesel fuel mixtures were developed. This approach reduces sampling artifacts and allows for the determination of optical properties, particle number concentration, and size distributions, along with several important gas phase species' concentrations. Findings indicate that biodiesel additions to diesel fuel do not necessarily have an air quality benefit for particulate emissions in this emission testing scenario. The often cited linear decrease in particulate emissions with increasing biodiesel content was not observed. Mixtures with half diesel and half biodiesel tended to have the highest particulate emissions in all size ranges. Mixtures with more than 50% biodiesel had slightly lower calculated mass for light absorbing carbon, but this reduction in mass is most likely a result of a shift in the size of the emission particles to a smaller size range, not a reduction in the total number of particles. Evaluation of the extensive optical properties from this experimental set-up indicates that biodiesel additions to diesel fuel has an impact on emission particle extinction in both visible and near-IR wavelengths. The B99 mixture had the smallest emission factor for extinction at 532 nm and at 1064 nm. For the extinction at 532 nm, the trend was not linear and the emission factor peaked at the B50 mixture. Results from intensive properties indicate that emissions from B5 and B25 mixtures have Ångström exponents close to 1, typical for black carbon emissions. The mixtures with a larger fraction of biodiesel have Ångström exponent values closer to 2, indicating more absorbing organic matter and/or smaller particle size in the emissions. Additional experimental testing should be completed to determine the application of these results and emission factors to other diesel vehicles or types of diesel and biodiesel fuel mixtures. Close

• 616. [Article] Assessing Transit Fare Equity in Utah Using a Geographic Information System

  The goal of this study is to develop and apply a new method for assessing social equity impacts of distance-based public transit fares. Shifting to a distance-based fare structure can disproportionately ...

  Citation × Citation Citation Abstract Copy Title: Assessing Transit Fare Equity in Utah Using a Geographic Information System Author: Farber, Steven, Batholomew, Keith, Li, Xiao, Paez, Antonio, Nurul Habib, Khandker M. Year: 2014 The goal of this study is to develop and apply a new method for assessing social equity impacts of distance-based public transit fares. Shifting to a distance-based fare structure can disproportionately favor or penalize different subgroups of a population based on variations in settlement patterns, travel needs, and most importantly, transit use. According to federal law, such disparities must be evaluated by the transit agency, but the area-based techniques identified by the Federal Transit Authority for assessing discrimination fail to account for disparities in distances travelled by transit users. This means that transit agencies currently lack guidelines for assessing the social equity impacts of replacing flat fare with distance-based fare structures. Our solution is to incorporate a joint ordinal-continuous model of trip generation and distance travelled into a GIS Decision Support System. The system enables a transit planner to visualize and compare estimated distances travelled and transit-cost maps for different population profiles and fare structures. We apply the method to a case study in the Wasatch Front, Utah, where the Utah Transit Authority is exploring a switch to a distance-based fare structure. The analysis reveals that overall distance-based fares benefit low-income, elderly, and non-white populations. However, the effect is geographically uneven, and may be negative for members of these groups living on the urban fringe. The research discusses a potential conflict between policies designed to promote equity and those intended to increase discretionary ridership. For example, increasing fares for longdistance discretionary riders travelling from suburban light-rail stations to the central business district may have a negative impact on ridership, despite being economically more efficient through cost-recapturing. At the same time, reducing fares for short-distance trips that are currently too expensive compared to private automobile travel may attract new riders. A full cost-benefit analysis sensitive to heterogeneous price elasticity is recommended for future research. It is also noted that the research findings are dependent on the current spatial distributions of population segments and travel patterns. The equity benefits of distance-based fares are primarily derived from residential clustering of low-income and minority groups in more compact urban areas near the center of the city. Demographic trends, such as inner-city gentrification and suburban aging-in-place, may impose increased travel demands on low income and elderly riders, nullifying future equity gains made by a transition to distance-based fares. Title: Assessing Transit Fare Equity in Utah Using a Geographic Information System Author: Farber, Steven, Batholomew, Keith, Li, Xiao, Paez, Antonio, Nurul Habib, Khandker M. Year: 2014 The goal of this study is to develop and apply a new method for assessing social equity impacts of distance-based public transit fares. Shifting to a distance-based fare structure can disproportionately favor or penalize different subgroups of a population based on variations in settlement patterns, travel needs, and most importantly, transit use. According to federal law, such disparities must be evaluated by the transit agency, but the area-based techniques identified by the Federal Transit Authority for assessing discrimination fail to account for disparities in distances travelled by transit users. This means that transit agencies currently lack guidelines for assessing the social equity impacts of replacing flat fare with distance-based fare structures. Our solution is to incorporate a joint ordinal-continuous model of trip generation and distance travelled into a GIS Decision Support System. The system enables a transit planner to visualize and compare estimated distances travelled and transit-cost maps for different population profiles and fare structures. We apply the method to a case study in the Wasatch Front, Utah, where the Utah Transit Authority is exploring a switch to a distance-based fare structure. The analysis reveals that overall distance-based fares benefit low-income, elderly, and non-white populations. However, the effect is geographically uneven, and may be negative for members of these groups living on the urban fringe. The research discusses a potential conflict between policies designed to promote equity and those intended to increase discretionary ridership. For example, increasing fares for longdistance discretionary riders travelling from suburban light-rail stations to the central business district may have a negative impact on ridership, despite being economically more efficient through cost-recapturing. At the same time, reducing fares for short-distance trips that are currently too expensive compared to private automobile travel may attract new riders. A full cost-benefit analysis sensitive to heterogeneous price elasticity is recommended for future research. It is also noted that the research findings are dependent on the current spatial distributions of population segments and travel patterns. The equity benefits of distance-based fares are primarily derived from residential clustering of low-income and minority groups in more compact urban areas near the center of the city. Demographic trends, such as inner-city gentrification and suburban aging-in-place, may impose increased travel demands on low income and elderly riders, nullifying future equity gains made by a transition to distance-based fares. Close

• 617. [Article] Groundwater-Surface Water Interactions near Mosier, Oregon

  The town of Mosier, Oregon, is located near the east, dry end of the Columbia River Gorge, and the local area is known for cherry orchards that rely heavily on groundwater for irrigation. The CRBG groundwater ...

  Citation × Citation Citation Abstract Copy Title: Groundwater-Surface Water Interactions near Mosier, Oregon Author: Jones, Cullen Brandon Year: 2016 The town of Mosier, Oregon, is located near the east, dry end of the Columbia River Gorge, and the local area is known for cherry orchards that rely heavily on groundwater for irrigation. The CRBG groundwater system in Mosier has experienced groundwater declines of up to 60 meters due to over-pumping and or commingling. Declining groundwater levels have led to concerns over the sustainability of the resource, as it is the principle water source for irrigation and domestic use. Despite numerous previous studies of groundwater flow in CRBG aquifers here and elsewhere in the Columbia River basin, an aspect that has received relatively little attention is the interaction between groundwater and surface waters at locations where interflow zones are intersected by the surface waters. The objective of my research is to investigate how CRBG interflow zone exposures in Mosier Creek may be controlling groundwater elevations in the area. The methods used include: (1) geochemical analysis of well cuttings and detailed geologic mapping along area streams to identify interflow zones of individual CRBG flows, (2) analysis of stream discharge data and groundwater elevation data to confirm exchange of groundwater and surface waters, and (3) collection and analyses of 31 water samples from area wells, streams, and springs, to determine if waters from individual CRBG aquifers can be hydrochemically identified and to further constrain understanding of surface and groundwater interactions. My study confirms that the general elevation of the Pomona Member and Basalt of Lolo interflow zone creek exposure is coincident with the elevation where a change in slope of the decline trend in 2004 is seen in Mosier area well hydrographs. Furthermore, the results of stream discharge data indicated a close connection between drawdown from groundwater pumping during irrigation season and groundwater- surface water interaction. At the time of drawdown in the upper-most CRBG aquifer (Pomona), the stream transitions from gaining to losing water into the groundwater system. Elemental chemistry data indicates the Frenchman Springs Sentinel Gap aquifer waters are the most evolved waters in this study. Stable isotopic data reinforced this determination as the Sentinel Gap waters are the lightest, or most negative, with regard to δD and δ18O. Sentinel Gap samples were more depleted than other aquifer samples by 4.38 to 6.89 0/100 for δD and 0.39 to 0.59 0/100 for δ18O. The results of the general chemistry and isotope data reveal a more evolved chemical signature in lower watershed groundwater versus a less evolved signature for waters from wells located higher up on the Columbia Hills anticline. This was interpreted to be the result of the major structural features in the area providing for a more regional pathway of recharge in lower watershed groundwaters, versus a more local source of recharge for upper watershed groundwaters. There was also a pronounced commingled signature in the elemental ratios of lower watershed aquifer waters. The suspected mechanism of recharge to lower watershed wells is through younger Cascadian deposits upslope from the local watershed. The findings of this study reveal the importance of a detailed understanding of CRBG stratigraphy and its relation to surface waters, especially for other areas within the Yakima Fold Belt or Oregon and Washington. Studies that do not consider the influence that individual CRBG flows can have on groundwater-surface water interactions, and the groundwater system as a whole, run the risk of improperly assessing the groundwater resource for a region. Title: Groundwater-Surface Water Interactions near Mosier, Oregon Author: Jones, Cullen Brandon Year: 2016 The town of Mosier, Oregon, is located near the east, dry end of the Columbia River Gorge, and the local area is known for cherry orchards that rely heavily on groundwater for irrigation. The CRBG groundwater system in Mosier has experienced groundwater declines of up to 60 meters due to over-pumping and or commingling. Declining groundwater levels have led to concerns over the sustainability of the resource, as it is the principle water source for irrigation and domestic use. Despite numerous previous studies of groundwater flow in CRBG aquifers here and elsewhere in the Columbia River basin, an aspect that has received relatively little attention is the interaction between groundwater and surface waters at locations where interflow zones are intersected by the surface waters. The objective of my research is to investigate how CRBG interflow zone exposures in Mosier Creek may be controlling groundwater elevations in the area. The methods used include: (1) geochemical analysis of well cuttings and detailed geologic mapping along area streams to identify interflow zones of individual CRBG flows, (2) analysis of stream discharge data and groundwater elevation data to confirm exchange of groundwater and surface waters, and (3) collection and analyses of 31 water samples from area wells, streams, and springs, to determine if waters from individual CRBG aquifers can be hydrochemically identified and to further constrain understanding of surface and groundwater interactions. My study confirms that the general elevation of the Pomona Member and Basalt of Lolo interflow zone creek exposure is coincident with the elevation where a change in slope of the decline trend in 2004 is seen in Mosier area well hydrographs. Furthermore, the results of stream discharge data indicated a close connection between drawdown from groundwater pumping during irrigation season and groundwater- surface water interaction. At the time of drawdown in the upper-most CRBG aquifer (Pomona), the stream transitions from gaining to losing water into the groundwater system. Elemental chemistry data indicates the Frenchman Springs Sentinel Gap aquifer waters are the most evolved waters in this study. Stable isotopic data reinforced this determination as the Sentinel Gap waters are the lightest, or most negative, with regard to δD and δ18O. Sentinel Gap samples were more depleted than other aquifer samples by 4.38 to 6.89 0/100 for δD and 0.39 to 0.59 0/100 for δ18O. The results of the general chemistry and isotope data reveal a more evolved chemical signature in lower watershed groundwater versus a less evolved signature for waters from wells located higher up on the Columbia Hills anticline. This was interpreted to be the result of the major structural features in the area providing for a more regional pathway of recharge in lower watershed groundwaters, versus a more local source of recharge for upper watershed groundwaters. There was also a pronounced commingled signature in the elemental ratios of lower watershed aquifer waters. The suspected mechanism of recharge to lower watershed wells is through younger Cascadian deposits upslope from the local watershed. The findings of this study reveal the importance of a detailed understanding of CRBG stratigraphy and its relation to surface waters, especially for other areas within the Yakima Fold Belt or Oregon and Washington. Studies that do not consider the influence that individual CRBG flows can have on groundwater-surface water interactions, and the groundwater system as a whole, run the risk of improperly assessing the groundwater resource for a region. Close

• 618. [Article] Educational achievement: shaping the region's reputation and driving its economy

  Any region’s reputation in education is a key to its economic vitality. Businesses look for signals of a quality workforce. Families want good schools for their children. The Portland-Vancouver region ...

  Citation × Citation Citation Abstract Copy Title: Educational achievement: shaping the region's reputation and driving its economy Author: Tapogna, John Year: 2007 Any region’s reputation in education is a key to its economic vitality. Businesses look for signals of a quality workforce. Families want good schools for their children. The Portland-Vancouver region is making progress in education, but the news is not uniformly good. On the positive side, Portland is rising in the ranks of so-called “well educated” cities—a reputation that benefits the region as a whole. Portland’s attractiveness to young, recent college graduates is well documented and has played an important role in the trend. The influx of young professionals is a plus for the regional economy. However, instability of K-12 school funding continues to cloud the region’s image. During the most recent recession, the national media frequently cited funding woes of Portland-area schools to illustrate the broader fiscal issues facing state and local governments. Despite the return of economic growth (and in some cases because of it), school-funding measures remained prominent on last November’s ballots. Fast-growing districts needed capital for expansion while the region’s largest district—Portland Public Schools—requested supplemental operating funds after two rounds of high-profile school closures. Unstable school finances remain a recognized problem, particularly in Oregon where volatile income taxes compose the majority of school revenue and the state plays no role in funding capital. During the past 15 years, the standards-based movement has focused attention on the achievements of elementary and secondary students like no other time in history. Across the region, a higher percentage of students in early grades meet state-established reading and math benchmarks than do middle- or highschool students. State legislatures and individual districts have responded with a host of reforms to address underachievement in the higher grades. Students in Washington State will take high school exit exams in reading, math, and writing beginning with the class of 2008. In Oregon, the State Board of Education is crafting more rigorous high-school diploma requirements, and school districts are experimenting with K-8 and small high school designs. The federal No Child Left Behind Act ensures that student achievement and school quality will remain in sharp focus in the coming years. Performance on state and federal reports will shape the region’s educational reputation and play a role in determining where in the region families and businesses locate. Title: Educational achievement: shaping the region's reputation and driving its economy Author: Tapogna, John Year: 2007 Any region’s reputation in education is a key to its economic vitality. Businesses look for signals of a quality workforce. Families want good schools for their children. The Portland-Vancouver region is making progress in education, but the news is not uniformly good. On the positive side, Portland is rising in the ranks of so-called “well educated” cities—a reputation that benefits the region as a whole. Portland’s attractiveness to young, recent college graduates is well documented and has played an important role in the trend. The influx of young professionals is a plus for the regional economy. However, instability of K-12 school funding continues to cloud the region’s image. During the most recent recession, the national media frequently cited funding woes of Portland-area schools to illustrate the broader fiscal issues facing state and local governments. Despite the return of economic growth (and in some cases because of it), school-funding measures remained prominent on last November’s ballots. Fast-growing districts needed capital for expansion while the region’s largest district—Portland Public Schools—requested supplemental operating funds after two rounds of high-profile school closures. Unstable school finances remain a recognized problem, particularly in Oregon where volatile income taxes compose the majority of school revenue and the state plays no role in funding capital. During the past 15 years, the standards-based movement has focused attention on the achievements of elementary and secondary students like no other time in history. Across the region, a higher percentage of students in early grades meet state-established reading and math benchmarks than do middle- or highschool students. State legislatures and individual districts have responded with a host of reforms to address underachievement in the higher grades. Students in Washington State will take high school exit exams in reading, math, and writing beginning with the class of 2008. In Oregon, the State Board of Education is crafting more rigorous high-school diploma requirements, and school districts are experimenting with K-8 and small high school designs. The federal No Child Left Behind Act ensures that student achievement and school quality will remain in sharp focus in the coming years. Performance on state and federal reports will shape the region’s educational reputation and play a role in determining where in the region families and businesses locate. Close

• 619. [Article] A Study of Headway Maintenance for Bus Routes: Causes and Effects of “Bus Bunching” in Extensive and Congested Service Areas

  A healthy and efficient public transit system is indispensable to reduce congestion, emissions, energy consumption, and car dependency in urban areas. The objective of this research is to 1) develop methods ...

  Citation × Citation Citation Abstract Copy Title: A Study of Headway Maintenance for Bus Routes: Causes and Effects of “Bus Bunching” in Extensive and Congested Service Areas Author: Figliozzi, Miguel A., Feng, Wu-chi, Lafferriere, Gerardo, Feng, Wei Year: 2012 A healthy and efficient public transit system is indispensable to reduce congestion, emissions, energy consumption, and car dependency in urban areas. The objective of this research is to 1) develop methods to evaluate and visualize bus service reliability for transit agencies in various temporal and spatial aggregation levels; 2) identify the recurrent unreliability trends of bus routes (focusing on high-frequency service periods) and understand their characteristics, causes and effects; and 3) model service times using linear regression models. This research utilized six months of archived automatic vehicle location (AVL) and automatic passenger count (APC) data from a low-performance route (Route 15) of TriMet, the public transit provider in the Portland metropolitan area. Route 15 has experienced difficulties in terms of schedule adherence and headway regularity. This research developed methods to summarize causes of bus bunching. We first determined the frequency of each cause (expressed as percentages) meeting pre-determined thresholds. Next, we performed a sensitivity analysis to demonstrate how cause percentage results change using varying difficulty levels of bus bunching thresholds. Finally, we investigated how cause percentage results vary spatially along different route segments. This research also developed novel ways to summarize and visualize vast amounts of bus route operations data in an insightful and intuitive manner: 1) a route/stop level visualization performance measure framework using color contour diagrams and 2) a dynamic interactive bus monitoring visualization framework based on a Google Maps platform. Visualizations proposed in this study can aid transit agency managers and operators to identify operational problems and better understand how such problems propagate spatially and temporally across routes. Finally, regression models were estimated to understand the key factors impacting dwell and travel times. Title: A Study of Headway Maintenance for Bus Routes: Causes and Effects of “Bus Bunching” in Extensive and Congested Service Areas Author: Figliozzi, Miguel A., Feng, Wu-chi, Lafferriere, Gerardo, Feng, Wei Year: 2012 A healthy and efficient public transit system is indispensable to reduce congestion, emissions, energy consumption, and car dependency in urban areas. The objective of this research is to 1) develop methods to evaluate and visualize bus service reliability for transit agencies in various temporal and spatial aggregation levels; 2) identify the recurrent unreliability trends of bus routes (focusing on high-frequency service periods) and understand their characteristics, causes and effects; and 3) model service times using linear regression models. This research utilized six months of archived automatic vehicle location (AVL) and automatic passenger count (APC) data from a low-performance route (Route 15) of TriMet, the public transit provider in the Portland metropolitan area. Route 15 has experienced difficulties in terms of schedule adherence and headway regularity. This research developed methods to summarize causes of bus bunching. We first determined the frequency of each cause (expressed as percentages) meeting pre-determined thresholds. Next, we performed a sensitivity analysis to demonstrate how cause percentage results change using varying difficulty levels of bus bunching thresholds. Finally, we investigated how cause percentage results vary spatially along different route segments. This research also developed novel ways to summarize and visualize vast amounts of bus route operations data in an insightful and intuitive manner: 1) a route/stop level visualization performance measure framework using color contour diagrams and 2) a dynamic interactive bus monitoring visualization framework based on a Google Maps platform. Visualizations proposed in this study can aid transit agency managers and operators to identify operational problems and better understand how such problems propagate spatially and temporally across routes. Finally, regression models were estimated to understand the key factors impacting dwell and travel times. Close

• 620. [Article] The Associations between Environmental Quality and Mortality in the Contiguous United States, 2000-2005

  Background: Assessing cumulative effects of the multiple environmental factors influencing mortality remains a challenging task. Objectives: This study aimed to examine the associations between cumulative ...

  Citation × Citation Citation Abstract Copy Title: The Associations between Environmental Quality and Mortality in the Contiguous United States, 2000-2005 Author: Jian, Yun, Messer, Lynne C., Jagai, Jyotsna S., Rappazzo, Kristen M., Gray, Christine L., Grabich, Shannon C., Lobdell, Danelle T. Year: 2016 Background: Assessing cumulative effects of the multiple environmental factors influencing mortality remains a challenging task. Objectives: This study aimed to examine the associations between cumulative environmental quality and all-cause and leading cause-specific (heart disease, cancer, and stroke) mortality rates. Methods: We used the overall Environmental Quality Index (EQI) and its five domain indices (air, water, land, built and sociodemographic) to represent environmental exposure. Associations between the EQI and mortality rates (CDC WONDER) for counties in the contiguous United States (n=3109) were investigated using multiple linear regression models, and random intercept, random slope hierarchical models. Urbanicity, climate and their combination were used to explore the spatial patterns in the associations. Results: We found one standard deviation increase in the overall EQI (worse environment) was associated with a mean 3.22% (95% CI: 2.80%, 3.64%) increase in all-cause mortality, a 0.54% (-0.17%, 1.25%) increase in heart disease mortality, a 2.71% (2.21%, 3.22%) increase in cancer mortality, and a 2.25% (1.11%, 3.39%) increase in stroke mortality. Among environmental domains, the associations ranged from -1.27% (-1.70%,-0.84%) to 3.37% (2.90%, 3.84%) for all-cause mortality, -2.62% (-3.52%, -1.73%) to 4.50% (3.73,5.27%) for heart disease mortality, -0.88% (2.12%,0.36%) to 3.72% (2.38%, to 5.06%) for stroke mortality, and -0.68% (-1.19%, -0.18%) to 3.01% (2.46%, 3.56%) for cancer mortality. Air had the largest associations with all-cause, heart disease, and cancer mortality, while the sociodemographic index had the largest association with stroke mortality. Across the urbanicity gradient, no consistent trend was found. Across climate regions, the associations ranged from 2.29% (1.87%, 2.72%) to 5.30% (4.30%, 6.30%) for overall EQI and higher associations were generally found in dry area for both overall EQI and domain indices. Conclusions: These results suggest that poor environmental quality, particularly air quality, was associated with increased mortality, and that associations vary by urbanicity and climate regions. Title: The Associations between Environmental Quality and Mortality in the Contiguous United States, 2000-2005 Author: Jian, Yun, Messer, Lynne C., Jagai, Jyotsna S., Rappazzo, Kristen M., Gray, Christine L., Grabich, Shannon C., Lobdell, Danelle T. Year: 2016 Background: Assessing cumulative effects of the multiple environmental factors influencing mortality remains a challenging task. Objectives: This study aimed to examine the associations between cumulative environmental quality and all-cause and leading cause-specific (heart disease, cancer, and stroke) mortality rates. Methods: We used the overall Environmental Quality Index (EQI) and its five domain indices (air, water, land, built and sociodemographic) to represent environmental exposure. Associations between the EQI and mortality rates (CDC WONDER) for counties in the contiguous United States (n=3109) were investigated using multiple linear regression models, and random intercept, random slope hierarchical models. Urbanicity, climate and their combination were used to explore the spatial patterns in the associations. Results: We found one standard deviation increase in the overall EQI (worse environment) was associated with a mean 3.22% (95% CI: 2.80%, 3.64%) increase in all-cause mortality, a 0.54% (-0.17%, 1.25%) increase in heart disease mortality, a 2.71% (2.21%, 3.22%) increase in cancer mortality, and a 2.25% (1.11%, 3.39%) increase in stroke mortality. Among environmental domains, the associations ranged from -1.27% (-1.70%,-0.84%) to 3.37% (2.90%, 3.84%) for all-cause mortality, -2.62% (-3.52%, -1.73%) to 4.50% (3.73,5.27%) for heart disease mortality, -0.88% (2.12%,0.36%) to 3.72% (2.38%, to 5.06%) for stroke mortality, and -0.68% (-1.19%, -0.18%) to 3.01% (2.46%, 3.56%) for cancer mortality. Air had the largest associations with all-cause, heart disease, and cancer mortality, while the sociodemographic index had the largest association with stroke mortality. Across the urbanicity gradient, no consistent trend was found. Across climate regions, the associations ranged from 2.29% (1.87%, 2.72%) to 5.30% (4.30%, 6.30%) for overall EQI and higher associations were generally found in dry area for both overall EQI and domain indices. Conclusions: These results suggest that poor environmental quality, particularly air quality, was associated with increased mortality, and that associations vary by urbanicity and climate regions. Close