The benefits of lower ozone due to air pollution emission reductions (2002–2011) in the Eastern United States during extreme heat

ABSTRACT

Using the Community Multiscale Air Quality (CMAQ) model and the Benefits Mapping and Analysis Program – Community Edition (BenMAP-CE) tool, we estimate the benefits of anthropogenic emission reductions between 2002 and 2011 in the Eastern United States (US) with respect to surface ozone concentrations and ozone-related health and economic impacts, during a month of extreme heat, July 2011. Based on CMAQ simulations using emissions appropriate for 2002 and 2011, we estimate that emission reductions since 2002 likely prevented 10– 15 ozone exceedance days (using the 2011 maximum 8-hr average ozone standard of 75 ppbv) throughout the Ohio River Valley and 5– 10 ozone exceedance days throughout the Washington, DC – Baltimore, MD metropolitan area during this extremely hot month. CMAQ results were fed into the BenMAP-CE tool to determine the health and health-related economic benefits of anthropogenic emission reductions between 2002 and 2011. We estimate that the concomitant health benefits from the ozone reductions were significant for this anomalous month: 160–800 mortalities (95% confidence interval (CI): 70–1,010) were avoided in July 2011 in the Eastern U.S, saving an estimated $1.3–$6.6 billion (CI: $174 million–$15.5 billion). Additionally, we estimate that emission reductions resulted in 950 (CI: 90–2,350) less hospital admissions from respiratory symptoms, 370 (CI: 180–580) less hospital admissions for pneumonia, 570 (CI: 0–1650) less Emergency Room (ER) visits from asthma symptoms, 922,020 (CI: 469,960–1,370,050) less minor restricted activity days (MRADs), and 430,240 (CI: ?280,350–963,190) less symptoms of asthma exacerbation during July 2011.

Implications: We estimate the benefits of air pollution emission reductions on surface ozone concentrations and ozone-related impacts on human health and the economy between 2002 and 2011 during an extremely hot month, July 2011, in the eastern United States (US) using the CMAQ and BenMAP-CE models. Results suggest that, during July 2011, emission reductions prevented 10-15 ozone exceedance days in the Ohio River Valley and 5-10 ozone exceedance days in the Mid Atlantic; saved 160-800 lives in the Eastern US, saving $1.3 - $6.5 billion; and resulted in 950 less hospital admissions for respiratory symptoms, 370 less hospital admissions for pneumonia, 570 less Emergency Room visits for asthma symptoms, 922,020 less minor restricted activity days, and 430,240 less symptoms of asthma exacerbation.     

Application of anaerobic and aerobic activated sludge to phosphorus-deficient wastewater treatment.

Anaerobic and aerobic (AnA) and completely aerobic (CA) sequencing-batch reactors (SBRs) were used to investigate the suitability of the AnA process for treating phosphorus (P)-deficient wastewaters with highly variable influent chemical oxygen demand (COD) loading. Both SBRs were subjected to influent COD loading patterns (LPs) that simulated (1) daily COD loading fluctuations, (2) weekend shutdowns, and (3) long weekend or holiday shutdowns. During LP 1, the AnA SBR produced lower average effluent soluble phosphorus concentrations than CA SBR (0.4 vs. 1.0 mgP/L). A similar result was observed during LP 2, but effluent acetate was detected after the first high COD loading cycle of the weekday loading period. During LP 3, the volatile suspended solids content of both reactors dropped sharply, and the effluent quality of both SBRs deteriorated. Model predictions suggest that the AnA process is stable when treating LP 1, but eventually fails when treating LP 2.     

Estimating rainforest biomass stocks and carbon loss from deforestation and degradation in Papua New Guinea 1972–2002: Best estimates,uncertainties and research needs

Reduction of carbon emissions from tropical deforestation and forest degradation is being considered a cost-effective way of mitigating the impacts of global warming. If such reductions are to be implemented, accurate and repeatable measurements of forest cover change and biomass will be required. In Papua New Guinea (PNG), which has one of the world's largest remaining areas of tropical forest, we used the best available data to estimate rainforest carbon stocks, and emissions from deforestation and degradation. We collated all available PNG field measurements which could be used to estimate carbon stocks in logged and unlogged forest. We extrapolated these plot-level estimates across the forested landscape using high-resolution forest mapping. We found the best estimate of forest carbon stocks contained in logged and unlogged forest in 2002 to be 4770 Mt (±13%). Our best estimate of gross forest carbon released through deforestation and degradation between 1972 and 2002 was 1178 Mt (±18%). By applying a long-term forest change model, we estimated that the carbon loss resulting from deforestation and degradation in 2001 was 53 Mt (±18%), rising from 24 Mt (±15%) in 1972. Forty-one percent of 2001 emissions resulted from logging, rising from 21% in 1972. Reducing emissions from logging is therefore a priority for PNG. The large uncertainty in our estimates of carbon stocks and fluxes is primarily due to the dearth of field measurements in both logged and unlogged forest, and the lack of PNG logging damage studies. Research priorities for PNG to increase the accuracy of forest carbon stock assessments are the collection of field measurements in unlogged forest and more spatially explicit logging damage studies.     

Patterns and ecological predictors of age-related performance in female North American barn swallows,Hirundo rustica erythrogaster

Life history theory describes the optimization of important trade-offs within an individual’s lifetime and predicts that an individual’s reproductive performance (RP) will improve up until a point of senescence. Despite abundant evidence for this pattern, relatively few studies consider the mechanisms associated with age-related improvements in RP. In this study, we aimed to describe patterns of age-related RP (seasonal fledgling production) in female North American barn swallows (Hirundo rustica erythrogaster) using a longitudinal data set to test multiple hypotheses about the social, morphological, and ecological factors underlying this prominent life history pattern. To address these objectives, we used generalized linear mixed models in a three-step series of analyses in which we assessed (1) patterns of female age-related RP; (2) the influence of age on changes in social, morphological, and ecological factors; and (3) whether the changes in RP were concomitant with changes in these factors. We found that (1) females showed patterns of age-related reproduction, in which performance increased in the first 2 years of breeding and decreased thereafter, (2) female tail streamer length increased and the extent of breast coloration increased then decreased significantly with age, and (3) changes in morphological traits did not covary with changes in reproductive performance over time. Our within-individual results highlight the importance of considering explicit links between morphology and reproductive performance that are not easily captured by population-level analyses.     

Assessment of the Applicability of Capsid-Integrity Assays for Detecting Infectious Norovirus Inactivated by Heat or UV Irradiation

Food and Environmental Virology - Human noroviruses are the leading cause of viral gastroenteritis. In the absence of a practical culture technique for routine analysis of infectious noroviruses,...     

Mountain goat response to hydroelectric exploration in northwestern British Columbia

The behavioral responses of more than 800 mountain goats, comprised of 195 social groups, were recorded during hydroelectric exploration activities (primarily aircraft) in northwestern British Columbia. Four categories of overt response were recorded during case tests, ranging from maintenance activity to severe flight. More than 80 percent (n=667) of the observed goats elicited some form of behavioral stress-response, with 33 percent (n=265) displaying a severe flight response to local rock or plant cover. Multiple regression analysis inferred goat responses to be statistically independent of the time of year, type, and vertical orientation of disturbance and group size. As expected, significant correlations (p≤0.05) existed between distance of disturbance, geographic area, cover availability, and degree of awareness. Responses were stimulated primarily by auditory and secondarily by visual cues. Repeated aerial and ground follow-up surveys documented temporary range abandonment and changing observability indices (habitat use and activity patterns) associated with areas of intense exploration activity. The assessed data offer mitigation possibilities and enable formulation of management guidelines to lessen project impacts during future exploration, construction, and operation phases.     

Putative temporal variability of Escherichia coli ribotypes from yearling steers

Escherichia coli is a ubiquitous component of the intestinal microflora of warm-blooded animals, and is an indicator of fecal contamination of surface waters. Ribotype profiling of E. coli is one of several genotypic methods that has been developed to determine the host origin of fecal bacteria. Like most genotypic methods of source tracking, ribotyping requires a host origin database to identify environmental isolates. To determine the extent of temporal variability of ribotypes and its effect on a host origin database, E. coli isolates were obtained from fecal samples of two herds of Black Angus steers at a long-term experimental site at four sampling times from October 1999 to July 2000. Fecal samples were taken from six randomly chosen steers at each time. At a similarity index of 90% as calculated by unweighted pair-group method using arithmetic averages (UPGMA), 240 ribotypes were identified from 451 E. coli isolates. Only 20 ribotypes (8.3%), comprising 33% of the total isolates, were shared among sampling times and were considered resident ribotypes. Two of the twenty resident ribotypes appeared at three sampling times, and the remaining eighteen appeared at two. The majority of the ribotypes, therefore, were transient and unique to each sampling time and steer. Both the apparent turnover of E. coli ribotypes and a clonal diversity index of 0.97 (indicative of extensive ribotype variability) suggest the necessity of ribotyping a large number E. coli isolates per host to establish a host origin database that is independent of temporal variability, or complete enough to be effective.