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The proposed multi-pollutant rule would further reduce air pollution from heavy-duty engines and vehicles across the United States, including ozone and particulate matter (PM). In addition, as part of this rulemaking, EPA is proposing targeted updates to the existing Heavy-Duty Greenhouse Gas Emissions Phase 2 program (HD GHG Phase 2).
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. Trends in daily maximum ozone levels (known as 4MDA8) at urban and non-urban sites.
of the human-made climate impact; two-thirds of this impact are caused by emissions other than CO 2 , according to a new study by researchers in Europe and the US. This new study is based on a thorough review of a decade of research on aviation emissions. The formation and emission of sulfate aerosol yields a negative (cooling) term.
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.
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. The results are less clear in Dallas and Houston.
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.
This analysis examined the effect of flight distance on greenhouse gas emissions per passenger, and compared emissions from flying different distances with annual emissions from driving. Greenhouse gas emissions were examined for 17 nonstop flights with round-trip distances ranging from 131 miles to 19,040 miles.
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).
Emissions of one of the chemicals most responsible for the Antarctic ozone hole are on the rise, despite an international treaty that required an end to its production in 2010, a new study by researchers at NOAA and their colleagues shows. However, that decrease is significantly slower than it would be without the new CFC emissions.
The decrease in CO 2 equivalent emissions of ODSs (ozone-depleting substances: CFCs, halons, HCFCs, and others) may be offset by the projected increase in their non-ozone depleting substitutes (HFCs) (lines designated as HFC scenarios). Climate and the Ozone Layer. Source: UNEP. Click to enlarge.
Black carbon and tropospheric ozone are harmful air pollutants that also contribute to climate change. Reducing black carbon and tropospheric ozone now will slow the rate of climate change within the first half of this century, the study said. Click to enlarge. °C (within a likely range of 0.2-0.7
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.
Among the many climate-related vulnerabilities that can impact its mission, the US Environmental Protection Agency (EPA) cites a likely increase in tropospheric ozone pollution as potentially making it more difficult to attain National Ambient Air Quality Standards ( NAAQS ) in many areas with existing ozone problems.
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.
When ethane and propane—the most abundant non-methane hydrocarbons (NMHC) in the atmosphere—mix with nitrogen oxides from vehicles and power plants they form tropospheric ozone—a key component of smog and directly linked to increases in mortality. —Professor Ally Lewis, a co-author of the study. Carpenter, Alastair C.
This continued shorter-term cooling response caused by certain emissions does not negate the necessity for reductions in CO 2 emissions, which are crucial to limiting the long-term warming impact of the sector, the researchers cautioned. of the total anthropogenic CO 2 emissions in that year.
Five technology paths for very-low-NO x and GHG emissions from heavy-duty natural gas engines. The “Pathways to Near-Zero-Emission Natural Gas Heavy Duty Vehicles” report, authored by GNA on behalf of Southern California Gas Co. An 80% reduction of GHG emissions is targeted for 2050, relative to 1990 levels. Click to enlarge.
CSIRO scientists have developed a new way to account for ozone in computer simulations of the climate. This latest modeling shows that the oceans take much less ozone out of the atmosphere than previously thought. Ozone (O 3 ) is formed by reactions of chemicals such as nitrogen oxides and volatile organic compounds—i.e.,
FTP cycle-weighted tailpipe emissions of N 2 O, NO x , and the sum of NMOG and NO x. The minimum in NO x and NMOG emissions for midlevel ethanol blends points to future opportunities for emission reductions from FFVs. Credit: ACS, Hubbard et al. Click to enlarge. E40); and the new range for high-level ethanol blends (E55, E80).
The program determines the environmental balance of vehicles with different size classes and powertrains, and presents the results in comparative graphics. The entire life cycle of the passenger cars is taken into account, including the manufacture of the vehicles and the environmentally relevant emissions from driving. in review).
The transportation sector was responsible for over 7 million tons of NO x emissions in the US in 2014, with 50% of this sector’s NO x attributed to heavy-duty on- and off-road vehicles and equipment. NO x is a precursor for both ground level ozone and secondary PM 2.5 Source of data: US EPA (2019). Chart: MECA.
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.
There was no significant difference in the profiles of total carbonyl emissions between CFT and DF. However, the use of CFT resulted in a remarkable reduction in carbonyl emissions in comparison with using DF. lower ozone formation potential of the carbonyl compounds present than DF under the identical operating conditions.
Power management company Eaton has introduced a complete suite of solutions from its Vehicle Group to reduce vapor emissions produced during the refueling of gasoline-powered vehicles. If fuel vapor is released into the atmosphere, it contributes to a category of pollutants known as evaporative emissions.
Contributions of regions to total life cycle emissions for three fuels (µg per vehicle-mile traveled per km 2 land area). Dashed lines show US average emissions. Associated tailpipe emissions alone account for 40?60% Credit: ACS, Tessum et al. Click to enlarge.
positive or negative—and magnitude of net climate forcing from BC emissions), currently available scientific and technical information provides a strong foundation for making mitigation decisions to achieve lasting benefits for public health, the environment, and climate. emissions in 2005. Earlier post.). Source: EPA.
Seasonal ethanol emissions from North America. Emissions for present-day are compared to those for the EISA and All-E85 scenarios. However, the significance of this effect will depend on the size of the emission change compared to that of the existing source fluxes, which are poorly known. Labels at left are months (e.g.,
Emission rates for the 1.7 A new study led by researchers at the University of Michigan compared regulated and unregulated emissions from both light-duty passenger car (1.7 Biodiesel also reduces smoke opacity, PM, CO, and NMHC emissions, although NO x may increase, depending on operating conditions. L engines at idle.
In particular, the study led by Drew Shindell found that methane emissions have a larger warming impact due to those interactions than accounted for in current carbon-trading schemes or in the Kyoto Protocol. And hydroxyls drive long chains of reactions involving other common gases, including ozone. Shindell et al.
Ethane reacts with sunlight and other molecules in the atmosphere to form ozone, which at the surface can cause respiratory problems, eye irritation and other ailments and damage crops. Two percent might not sound like a lot, but the emissions we observed in this single region are 10 to 100 times larger than reported in inventories.
Consumer products such as shampoo, cleaning products and paint now contribute as much to emitted volatile organic compounds (VOCs) in cities as tailpipe emissions from vehicles, according to a new study led by NOAA. Total VOC emission factors for end uses of petrochemical sources in the study. McDonald et al. Click to enlarge.
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
These connections arise because in many cases the agents of concern are the same, and in many cases the sources of the agents are the same or intimately connected.For example, surface ozone is both an air pollutant and a greenhouse gas. The complex roles that ozone and aerosols play in the atmosphere provide examples of such trade-offs.
The program will demonstrate that a suite of commercially available, EPA-rail-certified engines present a near-term, low-risk solution to create an affordable RNG hybrid line-haul locomotive with near zero emissions while simultaneously improving fuel cost by 50%. g/bhp-hr of NOx, a reduction of 400 times. g/bhp-hr of PM.
Source: Staff presentation. The California Air Resources Board directed its staff to take steps to provide further locomotive and rail yard emission reductions beyond those achieved by existing US Environmental Protection Agency and state regulations and agreements. With Five Locomotive Measures Click to enlarge.
Current emissions of anthropogenic greenhouse gases (GHGs) have already committed the planet to an increase in average surface temperature by the end of the century that may be above the critical threshold for tipping elements of the climate system into abrupt change with potentially irreversible and unmanageable consequences, the authors write.
The First Update will be presented to the Board on 22 May 2014 for consideration for approval. The AB 32 Scoping Plan, which guides development and implementation of California’s greenhouse gas emission reduction programs. The Air Resources Board is required to update the Scoping Plan every five years. —First update.
Ozonolysis—the cleavage of carbon-carbon double bonds through reaction with ozone—is a reaction that plays a key role in a number of fields, including synthetic chemistry and tropospheric removal of unsaturated hydrocarbons. —Professor Dudley Shallcross, Professor in Atmospheric Chemistry at The University of Bristol.
The $461,000-project, titled “Heterogeneous Aging Mechanisms of Combustion and Biomass Burning Emissions,” will focus on how gases, such as ozone, react with pollutants emitted from power plants and forest fires. Both types of emissions cause tiny particles to be suspended in air.
The on-road transportation (ORT) and power generation (PG) sectors are major contributors to CO 2 emissions and a host of short-lived radiatively-active air pollutants, including tropospheric ozone and fine aerosol particles, that exert complex influences on global climate. database) from another global inventory for the year 1996.
Short-lived climate pollutants (SLCPs) include methane, tropospheric ozone, black carbon, and fluorinated gases. Senate Bill 605 (Lara, Chapter 523, Statutes of 2014) requires ARB, in coordination with other state agencies and local air districts, to develop a SLCP Strategy by the end of 2015, to further reduce SLCP emissions in California.
A new study quantifying emissions from a fleet of gasoline direct injection (GDI) engines and port fuel injection (PFI) engines finds that the measured decrease in CO 2 emissions from GDIs is much greater than the potential climate forcing associated with higher black carbon emissions from GDI engines.
Ground-level ozone. Filtering outside air accounts for only half of CleanZone’s holistic approach to improving the driver’s environment; the other half is minimizing harmful emissions within the car. Volvo Cars has also implemented a test program to monitor and control emissions. Emissions Health Vehicle Systems'
A study led by researchers at UC Berkeley has found that diesel exhaust forms about seven times more secondary organic aerosols (SOA) than gasoline exhaust for the same mass of unburned fuel emissions and, given emission factors, can be expected to form 15 times more SOA than gasoline per liter of fuel burned.
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