A CHANGE POINT ANALYSIS OF THE IMPACT OF “ENVIRONMENTAL FEDERALISM” ON AGGREGATE AIR QUALITY IN THE UNITED STATES: 1940-98

2006 ◽  
Vol 44 (1) ◽  
pp. 109-120 ◽  
Author(s):  
THOMAS B. FOMBY ◽  
LIMIN LIN
Keyword(s):  
United States ◽  
Air Quality ◽  
Change Point ◽  
The United States ◽  
Change Point Analysis ◽  
Environmental Federalism ◽  
Point Analysis ◽  
The Impact

scholarly journals Reduction in hospitalisations for acute gastroenteritis-associated childhood seizures since introduction of rotavirus vaccination: a time-series and change-point analysis of hospital admissions in England

2019 ◽  
Vol 73 (11) ◽  
pp. 1020-1025 ◽  
Author(s):  
Daniel James Hungerford ◽  
Neil French ◽  
Miren Iturriza-Gómara ◽  
Jonathan M Read ◽  
Nigel A Cunliffe ◽  
...  
Keyword(s):  
Time Series ◽  
Acute Gastroenteritis ◽  
Change Point ◽  
Hospital Admissions ◽  
Population Level ◽  
Febrile Seizures ◽  
Change Point Analysis ◽  
Rotavirus Vaccination ◽  
Point Analysis ◽  
The Impact

IntroductionThe incidence of severe childhood diarrhoea has fallen substantially following the introduction of rotavirus vaccine in the UK in July 2013. Since children with rotavirus infection may experience febrile and afebrile seizures, we evaluated the impact of rotavirus vaccination on seizure hospitalisations in children in England.MethodsUsing data from Hospital Episode Statistics, we employed interrupted time-series analyses to assess changes in monthly hospital admissions for seizures among children aged <5 years from July 2000 to June 2017. Outcome measures comprised all seizures and febrile seizures, with and without a co-diagnosis of acute gastroenteritis (AGE). Models were adjusted for pneumococcal conjugate vaccine (PCV) introduction. Change-point analysis was used to independently identify step-changes in the time-series.ResultsAmong hospitalised children aged <5 years, the incidence of any seizures and febrile seizures with AGE decreased post-vaccine introduction by 23% (95% CI: 11% to 33%) and 31% (95% CI: 19% to 41%), respectively. For febrile seizures with AGE, a single change-point was identified in July 2013 (95% CI: June 2013 to December 2013). Reductions in seizure incidence were higher during the rotavirus season (49%, 95% CI: 37% to 58%) compared with out-of-season (13%, 95% CI: −4 to 28%) and showed no relation to PCV introduction. There were small reductions in any seizures with any co-diagnosis (4%, 95% CI: 0% to 8%) and in febrile seizures with any co-diagnosis (10%, 95% CI: 2% to 16%).ConclusionRotavirus vaccination has reduced hospitalisations for seizures associated with AGE in England, providing additional evidence of population-level impact of rotavirus vaccination on seizure incidence in high-income countries.

scholarly journals The impact of weather changes on air quality and health in the United States in 1994–2012

2015 ◽  
Vol 10 (8) ◽  
pp. 084009 ◽  
Author(s):  
Iny Jhun ◽  
Brent A Coull ◽  
Joel Schwartz ◽  
Bryan Hubbell ◽  
Petros Koutrakis
Keyword(s):  
United States ◽  
Air Quality ◽  
The United States ◽  
Weather Changes ◽  
The Impact

scholarly journals The impact of stay-at-home orders on air-quality and COVID-19 mortality rate in the United States

Urban Climate ◽  
2021 ◽  
pp. 100946
Author(s):  
Samain Sabrin ◽  
Maryam Karimi ◽  
Rouzbeh Nazari ◽  
Md Golam Rabbani Fahad ◽  
Robert W. Peters ◽  
...  
Keyword(s):  
United States ◽  
Air Quality ◽  
Mortality Rate ◽  
The United States ◽  
The Impact ◽  
At Home

scholarly journals Satellite-based estimation of the impacts of summertime wildfires on PM<sub>2.5</sub> concentration in the United States

2021 ◽  
Vol 21 (14) ◽  
pp. 11243-11256
Author(s):  
Zhixin Xue ◽  
Pawan Gupta ◽  
Sundar Christopher
Keyword(s):  
United States ◽  
Particulate Matter ◽  
Air Quality ◽  
Fine Particulate Matter ◽  
Atmospheric Correction ◽  
Health Assessment ◽  
The United States ◽  
Ancillary Data ◽  
Leave One Out ◽  
The Impact

Abstract. Frequent and widespread wildfires in the northwestern United States and Canada have become the “new normal” during the Northern Hemisphere summer months, which significantly degrades particulate matter air quality in the United States. Using the mid-visible Multi Angle Implementation of Atmospheric Correction (MAIAC) satellite-derived aerosol optical depth (AOD) with meteorological information from the European Centre for Medium-Range Weather Forecasts (ECMWF) and other ancillary data, we quantify the impact of these fires on fine particulate matter concentration (PM2.5) air quality in the United States. We use a geographically weighted regression (GWR) method to estimate surface PM2.5 in the United States between low (2011) and high (2018) fire activity years. Our results indicate an overall leave-one-out cross-validation (LOOCV) R2 value of 0.797 with root mean square error (RMSE) between 3 and 5 µg m−3. Our results indicate that smoke aerosols caused significant pollution changes over half of the United States. We estimate that nearly 29 states have increased PM2.5 during the fire-active year and that 15 of these states have PM2.5 concentrations more than 2 times that of the inactive year. Furthermore, these fires increased the daily mean surface PM2.5 concentrations in Washington and Oregon by 38 to 259 µg m−3, posing significant health risks especially to vulnerable populations. Our results also show that the GWR model can be successfully applied to PM2.5 estimations from wildfires, thereby providing useful information for various applications such as public health assessment.

scholarly journals Satellite-based Estimation of the Impacts of Summertime Wildfires on Particulate Matter Air Quality in United States

2020 ◽  
Author(s):  
Zhixin Xue ◽  
Pawan Gupta ◽  
Sundar Christopher
Keyword(s):  
United States ◽  
Particulate Matter ◽  
Air Quality ◽  
Fine Particulate Matter ◽  
Atmospheric Correction ◽  
Health Assessment ◽  
The United States ◽  
Ancillary Data ◽  
Weather Forecasts ◽  
The Impact

Abstract. Frequent and widespread wildfires in North Western United States and Canada has become the new normal during the northern hemisphere summer months, which degrades particulate matter air quality in the United States significantly. Using the mid-visible Multi Angle Implementation of Atmospheric Correction (MAIAC) satellite-derived Aerosol Optical Depth (AOD) with meteorological information from the European Centre for Medium-Range Weather Forecasts (ECMWF) and other ancillary data, we quantify the impact of these fires on fine particulate matter air quality (PM2.5) in the United States. We use a Geographically Weighted Regression method to estimate surface PM2.5 in the United States between low (2011) and high (2018) fire activity years. Our results indicate that smoke aerosols caused significant pollution changes over half of the United States. We estimate that nearly 29 states have increased PM2.5 during the fire active year and 15 of these states have PM2.5 concentrations more than 2 times than that of the inactive year. Furthermore, these fires increased daily mean surface PM2.5 concentrations in Washington and Oregon by 38 to 259 µgm−3 posing significant health risks especially to vulnerable populations. Our results also show that the GWR model can be successfully applied to PM2.5 estimations from wildfires thereby providing useful information for various applications including public health assessment.

scholarly journals Examining the impact of heterogeneous nitryl chloride production on air quality across the United States

2012 ◽  
Vol 12 (2) ◽  
pp. 6145-6183 ◽  
Author(s):  
G. Sarwar ◽  
H. Simon ◽  
P. Bhave ◽  
G. Yarwood
Keyword(s):  
United States ◽  
Air Quality ◽  
Atmospheric Chemistry ◽  
Forest Fires ◽  
The United States ◽  
Anthropogenic Sources ◽  
Reactive Nitrogen ◽  
Nitryl Chloride ◽  
The Impact ◽  
Hydrolysis Of

Abstract. The heterogeneous hydrolysis of dinitrogen pentoxide (N2O5) has typically been modeled as only producing nitric acid. However, recent field studies have confirmed that the presence of particulate chloride alters the reaction product to produce nitryl chloride (ClNO2) which undergoes photolysis to generate chlorine atoms and nitrogen dioxide (NO2). Both chlorine and NO2 affect atmospheric chemistry and air quality. We present an updated gas-phase chlorine mechanism that can be combined with the Carbon Bond 05 mechanism and incorporate the combined mechanism into the Community Multiscale Air Quality modeling system. We then update the current model treatment of heterogeneous hydrolysis of N2O5 to include ClNO2 as a product. The model, in combination with a comprehensive inventory of chlorine compounds, reactive nitrogen, particulate matter, and organic compounds, is used to evaluate the impact of the heterogeneous ClNO2 production on air quality across the United States for the months of February and September in 2006. The heterogeneous production increases ClNO2 in coastal as well as many in-land areas in the United States. Particulate chloride derived from sea-salts, anthropogenic sources, and forest fires activates the heterogeneous production of ClNO2. With current estimates of tropospheric emissions burden, it modestly enhances monthly mean 8-h ozone (up to 1–2 ppbv or 3–4%) but causes large increases (up to 13 ppbv) in isolated episodes. It also substantially reduce the mean total nitrate by up to 0.8–2.0 μg m−3 or 11–21%. Modeled ClNO2 accounts for up to 3–4% of the monthly mean total reactive nitrogen. Sensitivity results of the model suggest that ClNO2 formation is limited more by the presence of particulate chloride than by the abundance of N2O5.

scholarly journals The impact of marine organics on the air quality of the western United States

2010 ◽  
Vol 10 (3) ◽  
pp. 6257-6278 ◽  
Author(s):  
B. Gantt ◽  
N. Meskhidze ◽  
A. G. Carlton
Keyword(s):  
United States ◽  
Air Quality ◽  
Atmospheric Chemistry ◽  
Environmental Protection Agency ◽  
Regional Scale ◽  
The United States ◽  
Coastal Areas ◽  
Western United States ◽  
The Us ◽  
The Impact

Abstract. The impact of marine organic emissions to the air quality in coastal areas of the western United States is studied using the latest version of the US Environmental Protection Agency (EPA) regional-scale Community Multiscale Air Quality (CMAQv4.7) modeling system. Emissions of marine isoprene, monoterpenes, and primary organic matter (POM) from the ocean are implemented into the model to provide a comprehensive view of the connection between ocean biology and atmospheric chemistry and air pollution. Model simulations show that marine organics can increase the concentration of PM2.5 by 0.1–0.3 μg m−3 (up to 5%) in coastal cities. This increase in the PM2.5 concentration is primarily attributed to the POM emissions, with small contributions from the marine isoprene and monoterpenes. When marine organic emissions are included, organic carbon (OC) concentrations over the remote ocean are increased by up to 50% (25% in coastal areas), values consistent with recent observational findings. This study is the first to quantify the air quality impacts from marine POM and monoterpenes for the United States, and highlights the need for inclusion of marine organic emissions in air quality models.

scholarly journals The impact of monthly variation of the Pacific–North America (PNA) teleconnection pattern on wintertime surface-layer aerosol concentrations in the United States

2016 ◽  
Vol 16 (8) ◽  
pp. 4927-4943 ◽  
Author(s):  
Jin Feng ◽  
Hong Liao ◽  
Jianping Li
Keyword(s):  
United States ◽  
Surface Layer ◽  
Air Quality ◽  
North America ◽  
Organic Carbon ◽  
Black Carbon ◽  
The United States ◽  
The Pacific ◽  
The Us ◽  
The Impact

Abstract. The Pacific–North America teleconnection (PNA) is the leading general circulation pattern in the troposphere over the region of North Pacific to North America during wintertime. This study examined the impacts of monthly variations of the PNA phase (positive or negative phase) on wintertime surface-layer aerosol concentrations in the United States (US) by analyzing observations during 1999–2013 from the Air Quality System of the Environmental Protection Agency (EPA-AQS) and the model results for 1986–2006 from the global three-dimensional Goddard Earth Observing System (GEOS) chemical transport model (GEOS-Chem). The composite analyses on the EPA-AQS observations over 1999–2013 showed that the average concentrations of PM2.5, sulfate, nitrate, ammonium, organic carbon, and black carbon aerosols over the US were higher in the PNA positive phases (25 % of the winter months examined, and this fraction of months had the highest positive PNA index values) than in the PNA negative phases (25 % of the winter months examined, and this fraction of months had the highest negative PNA index values) by 1.0 µg m−3 (8.7 %), 0.01 µg m−3 (0.5 %), 0.3 µg m−3 (29.1 %), 0.1 µg m−3 (11.9 %), 0.6 µg m−3 (13.5 %), and 0.2 µg m−3 (27.8 %), respectively. The simulated geographical patterns of the differences in concentrations of all aerosol species between the PNA positive and negative phases were similar to observations. Based on the GEOS-Chem simulation, the pattern correlation coefficients were calculated to show the impacts of PNA-induced variations in meteorological fields on aerosol concentrations. The PNA phase was found (i) to influence sulfate concentrations mainly through changes in planetary boundary layer height (PBLH), precipitation (PR), and temperature; (ii) to influence nitrate concentrations mainly through changes in temperature; and (iii) to influence concentrations of ammonium, organic carbon, and black carbon mainly through changes in PR and PBLH. Results from this work have important implications for the understanding and prediction of air quality in the US.

scholarly journals Examining the impact of heterogeneous nitryl chloride production on air quality across the United States

2012 ◽  
Vol 12 (14) ◽  
pp. 6455-6473 ◽  
Author(s):  
G. Sarwar ◽  
H. Simon ◽  
P. Bhave ◽  
G. Yarwood
Keyword(s):  
United States ◽  
Air Quality ◽  
Atmospheric Chemistry ◽  
Forest Fires ◽  
The United States ◽  
Anthropogenic Sources ◽  
Reactive Nitrogen ◽  
Nitryl Chloride ◽  
The Impact ◽  
Hydrolysis Of

Abstract. The heterogeneous hydrolysis of dinitrogen pentoxide (N2O5) has typically been modeled as only producing nitric acid. However, recent field studies have confirmed that the presence of particulate chloride alters the reaction product to produce nitryl chloride (ClNO2) which undergoes photolysis to generate chlorine atoms and nitrogen dioxide (NO2). Both chlorine and NO2 affect atmospheric chemistry and air quality. We present an updated gas-phase chlorine mechanism that can be combined with the Carbon Bond 05 mechanism and incorporate the combined mechanism into the Community Multiscale Air Quality (CMAQ) modeling system. We then update the current model treatment of heterogeneous hydrolysis of N2O5 to include ClNO2 as a product. The model, in combination with a comprehensive inventory of chlorine compounds, reactive nitrogen, particulate matter, and organic compounds, is used to evaluate the impact of the heterogeneous ClNO2 production on air quality across the United States for the months of February and September in 2006. The heterogeneous production increases ClNO2 in coastal as well as many in-land areas in the United States. Particulate chloride derived from sea-salts, anthropogenic sources, and forest fires activates the heterogeneous production of ClNO2. With current estimates of tropospheric emissions, it modestly enhances monthly mean 8-h ozone (up to 1–2 ppbv or 3–4%) but causes large increases (up to 13 ppbv) in isolated episodes. This chemistry also substantially reduces the mean total nitrate by up to 0.8–2.0 μg m−3 or 11–21%. Modeled ClNO2 accounts for up to 6% of the monthly mean total reactive nitrogen. Sensitivity results of the model suggest that heterogeneous production of ClNO2 can further increase O3 and reduce TNO3 if elevated particulate-chloride levels are present in the atmosphere.

scholarly journals Impact of lightning-NO on eastern United States photochemistry during the summer of 2006 as determined using the CMAQ model

2012 ◽  
Vol 12 (4) ◽  
pp. 1737-1758 ◽  
Author(s):  
D. J. Allen ◽  
K. E. Pickering ◽  
R. W. Pinder ◽  
B. H. Henderson ◽  
K. W. Appel ◽  
...  
Keyword(s):  
United States ◽  
Air Quality ◽  
Wet Deposition ◽  
Surface Ozone ◽  
The United States ◽  
South Central ◽  
Southeastern Us ◽  
The Mean ◽  
The Impact ◽  
No Emissions

Abstract. A lightning-nitrogen oxide (NO) algorithm is implemented in the Community Multiscale Air Quality Model (CMAQ) and used to evaluate the impact of lightning-NO emissions (LNOx) on tropospheric photochemistry over the United States during the summer of 2006. For a 500 mole per flash lightning-NO source, the mean summertime tropospheric NO2 column agrees with satellite-retrieved columns to within −5 to +13%. Temporal fluctuations in the column are moderately well simulated; however, the addition of LNOx does not lead to a better simulation of day-to-day variability. The contribution of lightning-NO to the model column ranges from ∼10% in the northern US to >45% in the south-central and southeastern US. Lightning-NO adds up to 20 ppbv to upper tropospheric model ozone and 1.5–4.5 ppbv to 8-h maximum surface layer ozone, although, on average, the contribution of LNOx to model surface ozone is 1–2 ppbv less on poor air quality days. LNOx increases wet deposition of oxidized nitrogen by 43% and total deposition of nitrogen by 10%. This additional deposition reduces the mean magnitude of the CMAQ low-bias in nitrate wet deposition with respect to National Atmospheric Deposition monitors to near zero. Differences in urban/rural biases between model and satellite-retrieved NO2 columns were examined to identify possible problems in model chemistry and/or transport. CMAQ columns were too large over urban areas. Biases at other locations were minor after accounting for the impacts of lightning-NO emissions and the averaging kernel on model columns. In order to obtain an upper bound on the contribution of uncertainties in NOy chemistry to upper tropospheric NOx low biases, sensitivity calculations with updated chemistry were run for the time period of the Intercontinental Chemical Transport Experiment (INTEX-A) field campaign (summer 2004). After adjusting for possible interferences in NO2 measurements and averaging over the entire campaign, these updates reduced 7–9 km biases from 32 to 17% and 9–12 km biases from 57 to 46%. While these changes lead to better agreement, a considerable unexplained NO2 low-bias remains in the uppermost troposphere.

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