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Ozone levels across much of North America and Europe dropped significantly between 2000 and 2014. People living in parts of southern Europe, South Korea and southern Japan and China also experienced more than 15 days a year of ozone levels above 70 ppb. Source: University of Leicester. Click to enlarge.
They found that the increase in ozone burden due to the spatial distribution change slightly exceeds the combined influences of the increased emission magnitude and global methane. Based on their findings, they suggested that emission increases in Southeast, East and South Asia may be most important for the ozone change.
A study by researchers at the University of Texas found that in general, use of plug-in hybrid electric vehicles (PHEVs) can lead to an increase in ozone during nighttime hours (due to decreased scavenging from both vehicles and EGU stacks) and a decrease in ozone during daytime hours.
In China, people breathe ozone-laden air two to six times more often than people in the United States, Europe, Japan, or South Korea, according to a new international study published in Environmental Science & Technology Letters. 2017 for one ozone metric. The inset shows ozone trends in Beijing (red) and Los Angeles (blue).
Springtime ozone distributions for 1984, 1995–2008 in the mid-troposphere (3.0–8.0 Springtime ozone levels above western North America are rising primarily due to air flowing eastward from the Pacific Ocean, a trend that is largest when the air originates in Asia. The US EPA recently proposed new tougher ground-level ozone standards.
The two combine in the atmosphere to make either nitric acid or peroxynitrous acid; the so-called branching ratio of these two chemicals is important in models of ozone production. This means less of the hydroxyl radical and nitrogen dioxide go away, leading to proportionately more ozone, mostly in polluted areas, Okumura said.
Through a recent modeling experiment, a team of NASA-funded researchers have found that future concentrations of carbon dioxide and ozone in the atmosphere and of nitrogen in the soil are likely to have an important but overlooked effect on the cycling of water from sky to land to waterways. Benjamin Felzer, Lehigh University.
The global market for rocket launches may require more stringent regulation in order to prevent significant damage to Earth’s stratospheric ozone layer in the decades to come, according to a new study by researchers in California and Colorado. Darin Toohey.
Although halogens released from long-lived anthropogenic substances, such as chlorofluorocarbons (CFCs), are the principal cause of the recent depletion of stratospheric ozone, recent observations show that very short-lived substances (VSLS), with lifetimes generally under six months, are also an important source of stratospheric halogens.
University of Kentucky Chemistry Professor Marcelo Guzman has received a three-year grant from the National Science Foundation (NSF) for research, education and outreach efforts in the field of environmental and atmospheric chemistry. Both types of emissions cause tiny particles to be suspended in air.
The first peer-reviewed study to directly quantify how emissions from oil and natural gas (O&NG) activities influence summertime tropospheric ozone (O 3 ) pollution in the Colorado Front Range confirms that chemical vapors from oil and gas activities are a significant contributor to the region’s chronic ozone problem.
and ozone at or above the current standards have been linked to neuroinflammation and high risk of Alzheimer’s disease (AD). suggesting long-term exposure to PM 2.5 , as well as ozone above the current US EPA standards, are associated with increased risk of Alzheimer’s disease. Exposures to concentrations of PM 2.5 g/m 3 in PM 2.5
Now, researchers from Sandia National Laboratory’s Combustion Research Facility, the University of Manchester and the University of Bristol report in a paper in Science the first direct kinetics measurements made of reactions of any gas-phase Criegee intermediate, in this case formaldehyde oxide (CH 2 OO). —Welz et al.
The results, published in an open-access paper in the journal Science , suggest that the focus of efforts to mitigate ozone formation and toxic chemical burdens need to be adjusted, the authors suggested. Jathar, Colorado State University and UC Davis; Ali Akherati, Colorado State University; Jose L. McDonald et al.
Researchers at North Carolina State University are developing an ozone-based pre-treatment technique (ozonolysis) to release sugars from the energy grass miscanthus for production into renewable fuels or chemicals with minimal generation of chemical waste streams and degradation of the carbohydrate components.
Researchers at Monash University in Victoria, Australia have found an increase in toxic compounds, a decrease in protein content and a decreased yield in plants grown under high CO 2 and drought conditions. High Ozone Decreases Yield. Dr Gleadow.
Cooking, cleaning and other routine household activities generate significant levels of volatile and particulate chemicals inside the average home, leading to indoor air quality levels on par with a polluted major city, according to a study by researchers at the University of Colorado Boulder. Earlier post.).
Furthermore, myclimate accounts for other warming effects of aircraft emissions (through changes in the ozone layer, initiation of contrails, formation of cirrus clouds, etc.) The present calculations of the emissions per distance used the shortest flight distances as listed at Web|Flyer.
The Bakken Formation, a shale oil and gas field in North Dakota and Montana, is emitting roughly 2% (about 250,000 tons per year) of the globe’s ethane, according to new study led by researchers at the University of Michigan. Hydrocarbons react with NO x and sunlight to produce ozone. Ground-level ozone leads to poor air quality.
lower ozone formation potential of the carbonyl compounds present than DF under the identical operating conditions. In addition, there was an 18.0–35.8% reduction in total carbonyls and a 3.4–100% 100% drop in individual carbonyls in the constant load/varying speed test mode. CFT had 16.5–44.1% —Hao et al. 2014.05.025.
In addition to CO 2 , other compounds such as ozone (O 3 ) precursors (nitrogen oxides (NO x =NO+NO 2 ), carbon monoxide (CO), and volatile organic compounds (VOCs)) and aerosols such as black carbon (BC) and organic carbon (OC) are emitted by ships. 1 from shipping in 2007, corresponding to 3.3% 1 of the total ship emissions in 2007.
Children living in polluted megacities are at increased risk for brain inflammation and neurodegenerative changes, including Alzheimer or Parkinson’s disease, according to a study led by University of Montana Professor Dr. Lilian Calderón-Garcidueñas and her colleagues.
Computer scientists at the University of California, San Diego have built a portable pollution sensors that transmit transmit their air quality readings to smart phones, allowing users to monitor air quality in real time. Boxes represent pollution reading locations during that window. Nikzad et al. Click to enlarge. —Nikzad et al.
A research team from Ford Motor Company and the University of Copenhagen has performed a systematic study of the vapor pressures of single and dual-blends of different alcohols with potential to be used as biofuels, including methanol; ethanol; 1- and 2-propanol; and 1-, 2-, i -, and t -butanol. Credit: ACS, Andersen et al.
The study, by a team of researchers from Carnegie Mellon University, University of Georgia, Aerodyne Research, California Air Resources Board (ARB), Ohio State University, UC Berkeley, and UC San Diego is published in the ACS journal Environmental Science & Technology. We estimate ozone and SOA formation potential.
Researchers at the University of Toronto have found that natural sunlight triggers the release of smog-forming NO x compounds from the grime that typically coats buildings, statues and other outdoor surfaces in urban areas. Among these compounds are nitrogen oxides. —James Donaldson.
Emissions for present-day are compared to those for the EISA and All-E85 scenarios. This is accompanied by a modest regional decrease in surface ozone (of order 1%). Seasonal ethanol emissions from North America. Numbers inset give the total North American ethanol source. Labels at left are months (e.g., Credit: ACS, Millet et al.
Although air quality co-benefits can be comparable to policy costs for present-day air quality and near-term US carbon policies, potential co-benefits rapidly diminish as carbon policies become more stringent. In 2011, 231 counties in the US exceeded the EPA’s regulatory standards for ozone, the main component of smog.
Researchers from the University of Minnesota have produced a spatially and temporally explicit life cycle inventory (LCI) of air pollutants from gasoline, ethanol derived from corn grain, and ethanol from corn stover for the contiguous US (the lower 48 states). Dashed lines show US average emissions. Credit: ACS, Tessum et al.
A new study led by researchers at the University of Michigan compared regulated and unregulated emissions from both light-duty passenger car (1.7 Unregulated pollutants also include ozone precursors and bioaccumulative and toxic compounds. Credit: ACS, Chin et al. Click to enlarge. L) and medium-duty (6.4
Traffic contributes more to NO x emissions in Europe than previously thought, according to a new study by a team at the University of Innsbruck. The modelled fleet average contribution suggests that at least 90% of urban NO x emissions should originate from diesel driven vehicles at the present location. —Karl et al.
Air pollution impairs the function of blood vessels in the lungs, according to a study of more than 16,000 patients presented at EuroEcho-Imaging 2016. and ozone on pulmonary circulation on the same day and over five and ten days. The population study showed a negative effect of PM 10 , PM 2.5
In the US, 200 million people live in areas where pollutants such as ozone and fine particulate matter exceed the standards. We have a 50-year window of opportunity between the time urban children experience the detrimental effects we are describing here and when they will present with mild cognitive impairment and dementia.
Researchers at the University of California San Francisco have engineered the industrial yeast S. fermentans ferments cellulosic feedstocks to acetate and ethanol, which the modified S. cerevisiae uses to produce methyl halides. Adapted from Bayer et al. Click to enlarge. cerevisiae to convert biomass to methyl halides with good yield.
Isoprene, a five-carbon diene formed naturally in plants and animals and a precursor of ozone, contributes more than 40% of these emissions. The scientists pointed out that converting the epoxides to aerosol is likely to be higher in polluted environments, because the aerosols’ acidity is generally higher when human activity is present.
In 2004, the Centralina region (the Greater Charlotte metro area, which straddles the North CarolinaSouth Carolina border) was designated as a non-attainment area for ozone under the Clean Air Act. What is the present-day status of hydrail, in terms of new projects and installations? Where does hydrail stand at present?
Take, for example, the tens of thousands of fossil-fueled ships that chug across the ocean, spewing plumes of pollutants that contribute to acid rain, ozone depletion, respiratory ailments, and global warming. Testing our technologies presents yet another set of challenges. Our team, based at the. Kate Murphy.
Ozone pollution across the continental United States will become far more difficult to keep in check as temperatures rise, according to new work led by the National Center for Atmospheric Research (NCAR). Ozone formation. Even short periods of unhealthy ozone levels can cause local death rates to rise. Scenario A2 and RCP 8.5.
A) shows the base case peak concentrations for O 3 (ozone), ClNO and HCl in parts-per-billion by volume (ppbv). (B) Under extreme circumstances, this previously unknown chemistry could account for up to 40 parts per billion (ppb) of ozone; the current US Environmental Protection Agency (EPA) 8-hour average standard is 75 ppb.
The largest systematic study ever conducted of human volunteers exposed to ozone air pollution has found no evidence of effects on the heart in its healthy, older participants, but did find effects on the volunteers’ ability to breathe, even at low ambient levels. Possible pathways by which ozone may cause adverse health effects.
A major new Health Effects Institute (HEI) report presents a study examining associations between exposures to relatively low levels of air pollution and several health outcomes among participants in 22 European cohorts. particle composition. particle composition.
Jacobson at Stanford University. 1990; Anisimov, 2007] and chemical production of ozone in already-polluted locations [Jacobson, 2008b]. These three gases are all greenhouse gases, and ozone is a surface air pollutant. Results of the study suggest that soot is second only to carbon dioxide in contributing to global warming.
A new study led by researchers from Northwestern University projects that if electric vehicles replaced 25% of combustion engine cars currently on the road, the United States would save approximately $17 billion annually by avoiding damages from climate change and air pollution. The open-access paper is published in AGU’s journal GeoHealth.
80.27, “high ozone season” means the period from June 1 to September 15 of any calendar year and “regulatory control period” means the period from May 1 to September 15 of any calendar year. The Effect of E100 Water Content on High Load Performance of a Spray Guide Direct Injection Boosted Engine (presentation). 40 CFR § 80.27
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