Search

The residual stresses within Allvac 718Plus bars built using LBPF with different laser powers, speeds and table displacements were measured using diffraction and mechanical methods and modelled with the baseplate attached and then removed. The residual stress profiles within the bars from the top surface down through the bulk were all quite similar, becoming less tensile due to a strain hardening mechanism. Table displacement has the greatest impact on residual stress, decreasing with increasing displacement/powder layer thickness. There was good agreement amongst the modeling and measurements. The microstructures were examined and varied slightly with energy density with higher densities having larger grains and enhanced post solidification diffusion. Energy density had minimal impact on the residuals stresses within the parameters to produce dense material.

Environ Health Perspect. 130(8):087007 (2022), https://doi.org/10.1289/EHP9999a A comma was misplaced in Table 1. In the last column (OTHER [Equation 4]), the value for Observations (n) should be 46,512 rather than [...]

Environ Health Perspect. 130(8): 087007 (2022), https://doi.org/10.1289/EHP9999a The caption of Figure 1 contained extraneous text. These errors did not affect the figure. The corrected Figure caption reads: Figure 1. Trends [...]

Background: This paper represents, to our knowledge, the first national-level (United States) estimate of the economic impacts of vibriosis cases as exacerbated by climate change. Vibriosis is an illness contracted through food- and waterborne exposures to various Vibrio species (e.g., non V. cholerae O1 and O139 serotypes) found in estuarine and marine environments, including within aquatic life, such as shellfish and finfish. Objectives: The objective of this study was to project climate-induced changes in vibriosis and associated economic impacts in the United States related to changes in sea surface temperatures (SSTs). Methods: For our analysis to identify climate links to vibriosis incidence, we constructed three logistic regression models by Vibrio species, using vibriosis data sourced from the Cholera and Other Vibrio Illness Surveillance system and historical SSTs. We relied on previous estimates of the cost-per-case of vibriosis to estimate future total annual medical costs, lost income from productivity loss, and mortality-related indirect costs throughout the United States. We separately reported results for V. parahaemolyticus, V. vulnificus, V. alginolyticus, and 'V. spp.,' given the different associated health burden of each. Results: By 2090, increases in SST are estimated to result in a 51% increase in cases annually relative to the baseline era (centered on 1995) under Representative Concentration Pathway (RCP) 4.5, and a 108% increase under RCP8.5. The cost of these illnesses is projected to reach $5.2 billion annually under RCP4.5, and $7.3 billion annually under RCP8.5, relative to $2.2billion in the baseline (2018 U.S. dollars), equivalent to 140% and 234% increases respectively. Discussion: Vibriosis incidence is likely to increase in the United States under moderate and unmitigated climate change scenarios through increases in SST, resulting in a substantial burden of morbidity and mortality, and costing billions of dollars. These costs are mostly attributable to deaths, primarily from exposure to V. vulnificus. Evidence suggests that other factors, including sea surface salinity, may contribute to further increases in vibriosis cases in some regions of the United States and should also be investigated. https://doi.org/10.1289/EHP9999a, Introduction Scientific evidence demonstrates that human-influenced climate change is occurring and is taking its toll on environmental and public health in numerous ways. Globally, air and ocean temperatures are increasing, [...]

Economic and health benefits assessments of air quality changes often quantify and report changes in deaths at a given point in time. The typical approach uses a method that attributes air pollution-related health impacts to a single year air quality change (or "pulse"). The perspective on benefits from these static pulse analyses can be enhanced by conducting a dynamic population assessment using life tables. Such analyses can provide a richer characterization of health risks across a population over a multiyear time horizon. In this article, we use the life table approach to quantify cumulative counts of reductions in PM-attributable deaths and life-years gained due to overlapping impacts of PM2.5 changes over a multiyear period, using case studies of air quality improvements in the USA and Chile. Our comparison of health risk and economic valuation for the two approaches shows life table analysis can be a valuable adjunct analysis to the pulse approach though both come with their own set of uncertainties and limitations. If applied jointly, they provide a broader characterization of how air quality actions can change populations in terms of life-years lost, life expectancy, and age structure. The value of these metrics is illustrated using case studies with dramatically different air quality reduction trajectories. [ABSTRACT FROM AUTHOR]

Section 812 of the Clean Air Act Amendments (CAAA) of 1990 requires the U.S. Environmental Protection Agency (EPA) to perform periodic, comprehensive analyses of the total costs and total benefits of programs implemented pursuant to the CAAA. The first prospective analysis was completed in 1999. The second prospective analysis was initiated during 2005. The first step in the second prospective analysis was the development of base and projection year emission estimates that will be used to generate benefit estimates of CAAA programs. This paper describes the analysis, methods, and results of the recently completed emission projections. There are several unique features of this analysis. One is the use of consistent economic assumptions from the Department of Energy's Annual Energy Outlook 2005 (AEO 2005) projections as the basis for estimating 2010 and 2020 emissions for all sectors. Another is the analysis of the different emissions paths for both with and without CAAA scenarios. Other features of this analysis include being the first EPA analysis that uses the 2002 National Emission Inventory files as the basis for making 48-state emission projections, incorporating control factor files from the Regional Planning Organizations (RPOs) that had completed emission projections at the time the analysis was performed, and modeling the emission benefits of the expected adoption of measures to meet the 8-hr ozone National Ambient Air Quality Standards (NAAQS), the Clean Air Visibility Rule, and the [PM.sub.2.5] NAAQS. This analysis shows that the 1990 CAAA have produced significant reductions in criteria pollutant emissions since 1990 and that these emission reductions are expected to continue through 2020. CAAA provisions have reduced volatile organic compound (VOC) emissions by approximately 7 million t/yr by 2000, and are estimated to produce associated VOC emission reductions of 16.7 million t by 2020. Total oxides of nitrogen (N[O.sub.x]) emission reductions attributable to the CAAA are 5, 12, and 17 million t in 2000, 2010, and 2020, respectively. Sulfur dioxide (S[O.sub.2]) emission benefits during the study period are dominated by electricity-generating unit (EGU) S[O.sub.2] emission reductions. These EGU emission benefits go from 7.5 million t reduced in 2000 to 15 million t reduced in 2020., INTRODUCTION Section 812 of the Clean Air Act Amendments (CAAA) of 1990 requires the U.S. Environmental Protection Agency (EPA) to perform periodic, comprehensive analyses of the total costs and total [...]

High tide flooding (HTF) already affects traffic in many US coastal areas, but the issue will worsen significantly in the future. While studies show that large storm surge events threaten to be ever more costly, less damaging, but more frequent HTF events remain understudied and potentially carry a comparable economic impact. This study advances our understanding of the risks and impacts of HTF on vulnerable traffic corridors using hourly tide gauge water levels, sea-level rise projections, and link-level spatial analysis. It is the first study to estimate HTF economic impacts for varying levels of intervention, including reasonably anticipated driver-initiated rerouting and ancillary protection of adjacent property. The 2020 annual national-level costs of $1.3 to $1.5 billion will increase to $28 to $37 billion in 2050 and $220 to $260 billion in 2100 for medium to high greenhouse gas (GHG) emissions scenarios, respectively. Total costs over the century are $1.0 to $1.3 trillion (discounted 3%). Additional cost-effective protection by building sea walls or raising road surfaces could significantly reduce 2100 costs to $61 to $78 billion, but there remain many barriers to adopting least-cost adaptation decisions, and these gains may only be realized with careful planning and information sharing. [ABSTRACT FROM AUTHOR]

Recent advancements in the availability of models and data to characterize the economic impacts of climate change have improved our ability to project both the physical impacts and economic effects of climate change across economic sectors of the United States. These advancements have in turn provided an opportunity to estimate these impacts across multiple economic sectors using a consistent set of damage functions. These functions can be used to inform decision making regarding the diversity and magnitude of future impacts and how adaptation and other actions can affect the risk of economic impacts. This article shows how damage functions can be developed from the results of detailed modeling studies and then used to estimate future economic impacts. We estimate damage functions based on 15 sectoral impact models that project the economic impacts of climate change on human health, infrastructure, and ecosystems and, with a focus on temperature, apply these functions to changes in economic impacts for seven U.S. regions through 2100. We also discuss the uncertainty of these results. We conclude that, although further research is needed, the methods presented here can be usefully applied to a range of alternative temperature trajectories to estimate the economic effects of climate change. [ABSTRACT FROM AUTHOR]

The U.S. Southwest is projected to experience increasing aridity due to climate change. We quantify the resulting impacts on ambient dust levels and public health using methods consistent with the Environmental Protection Agency's Climate Change Impacts and Risk Analysis framework. We first demonstrate that U.S. Southwest fine (PM2.5) and coarse (PM2.5‐10) dust levels are strongly sensitive to variability in the 2‐month Standardized Precipitation‐Evapotranspiration Index across southwestern North America. We then estimate potential changes in dust levels through 2099 by applying the observed sensitivities to downscaled meteorological output projected by six climate models following an intermediate (Representative Concentration Pathway 4.5, RCP4.5) and a high (RCP8.5) greenhouse gas concentration scenario. By 2080–2099 under RCP8.5 relative to 1986–2005 in the U.S. Southwest: (1) Fine dust levels could increase by 57%, and fine dust‐attributable all‐cause mortality and hospitalizations could increase by 230% and 360%, respectively; (2) coarse dust levels could increase by 38%, and coarse dust‐attributable cardiovascular mortality and asthma emergency department visits could increase by 210% and 88%, respectively; (3) climate‐driven changes in dust concentrations can account for 34–47% of these health impacts, with the rest due to increases in population and baseline incidence rates; and (4) economic damages of the health impacts could total $47 billion per year additional to the 1986–2005 value of $13 billion per year. Compared to national‐scale climate impacts projected for other U.S. sectors using the Climate Change Impacts and Risk Analysis framework, dust‐related mortality ranks fourth behind extreme temperature‐related mortality, labor productivity decline, and coastal property loss. Plain Language Summary: The southwestern United States is projected to experience severe, multidecadal droughts due to human‐caused climate change. Mineral dust particles are a major contributor to air pollution in this region due to abundant deserts and drylands. To what extent could airborne dust levels increase as a result of the projected drought conditions? To answer this question, we first investigate the influence of drought conditions across southwestern North America on dust activity in recent years. We then use the observed relationships between dust and droughts to estimate future changes in dust levels—and the associated excess deaths and illnesses—through the end of the century, using projections of temperature and precipitation from global climate models following two plausible (high and intermediate) greenhouse gas emissions scenarios. Under the high emissions scenario, premature mortality associated with dust exposure increases by 220% and hospitalization increases by 160% toward the end of this century, due to combined increases in population, disease rates, and dust levels. The annual economic damages of these health impacts are estimated to be $47 billion per year additional to the present‐day value of $13 billion per year, making climate‐driven changes in dust concentrations one of the costliest impacts projected for the United States so far. Key Points: Increasing aridity may cause dust levels in the U.S. Southwest to rise by 40% in 2090 under a high greenhouse gas concentration scenarioDust‐related mortality could increase by 220% in 2090 under the high scenarioEstimated economic damages from dust‐related mortality make this one of the costliest climate impacts projected for the United States so far [ABSTRACT FROM AUTHOR]

Pollen is an important environmental cause of allergic asthma episodes. Prior work has established a proof of concept for assessing projected climate change impacts on future oak pollen exposure and associated health impacts. This paper uses additional monitor data and epidemiologic functions to extend prior analyses, reporting new estimates of the current and projected future health burden of oak, birch, and grass pollen across the contiguous United States. Our results suggest that tree pollen in the spring currently accounts for between 25,000 and 50,000 pollen‐related asthma emergency department (ED) visits annually (95% confidence interval: 14,000 to 100,000), roughly two thirds of which occur among people under age 18. Grass pollen in the summer season currently accounts for less than 10,000 cases annually (95% confidence interval: 4,000 to 16,000). Compared to a baseline with 21st century population growth but constant pollen, future temperature and precipitation show an increase in ED visits of 14% in 2090 for a higher greenhouse gas emissions scenario, but only 8% for a moderate emissions scenario, reflecting projected increases in pollen season length. Grass pollen, which is more sensitive to changes in climatic conditions, is a primary contributor to future ED visits, with the largest effects in the Northeast, Midwest, and Southern Great Plains regions. More complete assessment of the current and future health burden of pollen is limited by the availability of data on pollen types (e.g., ragweed), other health effects (e.g., other respiratory disease), and economic consequences (e.g., medication costs). Key Points: We link pollen, climate, and epidemiological data to estimate the health burden of oak, birch, and grass pollen across the contiguous United StatesWe found that 35,000 to 60,000 asthma emergency department visits (two thirds of these among children) may be linked with pollen each yearWe project that future climate changes could increase pollen‐related asthma emergency department visits by 14% in 2090 [ABSTRACT FROM AUTHOR]

A study is presented which seeks to evaluate the possible risk to the United States economy of change in climatic conditions. Specific attention is given to the economic results of sea level rise caused by the greenhouse effect.

Climate change will have potentially significant effects on freshwater quality due to increases in river and lake temperatures, changes in the magnitude and seasonality of river runoff, and more frequent and severe extreme events. These physical impacts will in turn have economic consequences through effects on riparian development, river and reservoir recreation, water treatment, harmful aquatic blooms, and a range of other sectors. In this paper, we analyze the physical and economic effects of changes in freshwater quality across the contiguous U.S. in futures with and without global-scale greenhouse gas mitigation. Using a water allocation and quality model of 2119 river basins, we estimate the impacts of various projected emissions outcomes on several key water quality indicators, and monetize these impacts with a water quality index approach. Under mitigation, we find that water temperatures decrease considerably and that dissolved oxygen levels rise in response. We find that the annual economic impacts on water quality of a high emissions scenario rise from $1.4 billion in 2050 to $4 billion in 2100, leading to present value mitigation benefits, discounted at 3%, of approximately $17.5 billion over the 2015-2100 period. [ABSTRACT FROM AUTHOR]

This paper considers the impact of sea level rise and storm surge on the Red River delta region of Vietnam. Permanently inundated lands and temporary flood zones are analyzed by combining sea level rise scenarios for 2050 with simulated storm surge levels for the 100-year event. Our analysis finds that sea level rise through 2050 could increase the effective frequency of the current 100-year storm surge, which is associated with a storm surge of roughly five meters, to once every 49 years. Approximately 10% of the Hanoi region's GDP is vulnerable to permanent inundation due to sea level rise, and more than 40% is vulnerable to periodic storm surge damage consistent with the current 100-year storm. We conclude that coastal adaptation measures, such as a planned retreat from the sea, and construction of a more substantial seawall and dike system, are needed to respond to these threats. [ABSTRACT FROM AUTHOR]

Climate change will have potentially significant effects on hydropower generation due to changes in the magnitude and seasonality of river runoff and increases in reservoir evaporation. These physical impacts will in turn have economic consequences through both producer revenues and consumer expenditures. We analyze the physical and economic effects of changes in hydropower generation for the contiguous U.S. in futures with and without global-scale greenhouse gas (GHG) mitigation, and across patterns from 18 General Circulation Models. Using a monthly water resources systems model of 2119 river basins that routes simulated river runoff through reservoirs, and allocates water to potentially conflicting and climate dependent demands, we provide a first-order estimate of the impacts of various projected emissions outcomes on hydropower generation, and monetize these impacts using outputs from an electric sector planning model for over 500 of the largest U.S. hydropower facilities. We find that, due to generally increasing river runoff under higher emissions scenarios in the Pacific Northwest, climate change tends to increase overall hydropower generation in the contiguous U.S. During low flow months, generation tends to fall with increasing emissions, potentially threatening the estimated low flow, firm energy from hydropower. Although global GHG mitigation slows the growth in hydropower generation, the higher value placed on carbon-free hydropower leads to annual economic benefits ranging from $1.8 billion to $4.3 billion. The present value of these benefits to the U.S. from global greenhouse gas mitigation, discounted at 3%, is $34 to $45 billion over the 2015–2050 period. [ABSTRACT FROM AUTHOR]

Future climate change is expected to lengthen and intensify pollen seasons in the U.S., potentially increasing incidence of allergic asthma. We developed a proof-of-concept approach for estimating asthma emergency department (ED) visits in the U.S. associated with present-day and climate-induced changes in oak pollen. We estimated oak pollen season length for moderate (Representative Concentration Pathway (RCP) 4.5) and severe climate change scenarios (RCP8.5) through 2090 using five climate models and published relationships between temperature, precipitation, and oak pollen season length. We calculated asthma ED visit counts associated with 1994-2010 average oak pollen concentrations and simulated future oak pollen season length changes using the Environmental Benefits Mapping and Analysis Program, driven by epidemiologically derived concentration-response relationships. Oak pollen was associated with 21,200 (95% confidence interval, 10,000-35,200) asthma ED visits in the Northeast, Southeast, and Midwest U.S. in 2010, with damages valued at $10.4 million. Nearly 70% of these occurred among children age <18 years. Severe climate change could increase oak pollen season length and associated asthma ED visits by 5% and 10% on average in 2050 and 2090, with a marginal net present value through 2090 of $10.4 million (additional to the baseline value of $346.2 million). Moderate versus severe climate change could avoid >50% of the additional oak pollen-related asthma ED visits in 2090. Despite several key uncertainties and limitations, these results suggest that aeroallergens pose a substantial U.S. public health burden, that climate change could increase U.S. allergic disease incidence, and that mitigating climate change may have benefits from avoided pollen-related health impacts., (©2017. The Authors.)