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New analysis has found increasing emissions of several ozone-depleting chemicals despite their production being banned for most uses under the Montreal Protocol—and a loophole in the rules is likely responsible. According to the researchers, emissions from these CFCs currently do not significantly threaten ozone recovery.
Reducing emissions of black carbon soot and ground-level ozone would quickly make a considerable dent in the climate change problem and would also contribute to public health and protect crop yields, according to an essay in the September/October issue of Foreign Affairs. Besides a danger to breathe, ozone lowers crop yields.
Annual average concentrations of fine particulates from US sources of combustion emissions from (a) electric power generation; (b) industry; (c) commercial and residential sources; (d) road transportation; (e) marine transportation; (f) rail transportation; (g) sum of all combustion sources; (h) all sources. Source: MIT.
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.
A study by a pair of researchers at Northwestern University found that when fuel prices drove residents of São Paulo, Brazil, to switch from ethanol to gasoline in their flexible-fuel vehicles, local ozone levels dropped 20%. Ozone levels are relatively high in São Paulo, with hourly concentrations above 75 and 125 µg m ?3
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.
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.
Counties where measured ozone is above proposed range of standards, based on 2011-2013 monitoring data. Earlier this year, EPA staff had recommended the further reduction of this primary ozone standard from the current 75 ppb (parts per billion) to a revised level within the range of 70 ppb to 60 ppb—and preferably below 70 ppb.
In a recent open-access paper published in ACS’ Environmental Science & Technology , researchers from the University of York report that alcohols in windshield washer fluid account for a larger fraction of real-world vehicle emissions than previous estimates have suggested. —Cliff et al.
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.
Radiative forcing due to perpetual constant year 2000 emissions grouped by sector for 2020 (left) and 2100 (right) showing the contribution from each species. This approach will make it easier to identify sectors for which emission reductions will be most beneficial for climate and those which may produce unintended consequences.”.
Ozone, the main component of smog, is a plant-damaging pollutant formed by emissions from vehicles, cooking stoves and other sources. New research shows that ozone pollution damaged millions of tons of wheat, rice, soybean and cotton crops in India in 2005. Surface ozone pollution in India damaged 6 million metric tons (6.7
Large improvements of air quality in China during the lockdown have been widely reported, but new research shows that two pollutants harmful to human health—fine particulate matter (PM 2.5 ) and ozone—were only slightly reduced. and ozone were only slightly reduced or barely affected.
Researchers from Rice University and the US Environmental Protection Agency (EPA) report in a paper in the journal Atmospheric Chemistry that particularly in Northeastern cities, ozone levels dropped even beyond what was anticipated by cutting emissions of NO x from 2002 to 2006. —Daniel Cohan, co-author. Earlier post.).
Rather, it is the leaking of hydrogen from production, transportation and usage that adds to global warming. Hydrogen is not a greenhouse gas, but its chemical reactions in the atmosphere affect greenhouse gases such as methane, ozone, and stratospheric water vapor. Sand et al. Hydrogen interacts with various biogeochemical processes.
The California Air Resources Board’s latest state inventory of greenhouse gas emissions shows that California’s GHG emissions continue to decrease. Trends in California GHG Emissions. Changes in emissions by Scoping Plan sector between 2000 and 2017. Emissions are organized by the categories in the AB 32 Scoping Plan.
Energy Secretary Steven Chu announced up to $10 million is available ( DE-FOA-0000669 ) this year to demonstrate and deploy electric transportation technologies for cargo vehicles, such as trucks, locomotives and forklifts. systems in roadbeds or rail lines that propel trucks or trains.
More than half of all air-quality-related early deaths in the United States are a result of emissions originating outside of the state in which those deaths occur, MIT researchers report in a paper in the journal Nature. Now it’s looking like other emissions sectors are becoming important. That wasn’t really possible before.
According to a study commissioned by the Washington, DC-based Propane Education & Research Council (PERC), NO x emissions measured from propane autogas school buses were substantially lower than those measured from diesel school buses. For the stop-and-go route, NO x emissions were 34 times higher for the diesel school bus.
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
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. Scenario A2 and RCP 8.5. The RCP 8.5
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.
Fast action on pollutants such as black carbon, ground-level ozone and methane may help limit near term global temperature rise and significantly increase the chances of keeping temperature rise below 2 °C (3.6 °F)—and emission reduction potential. Extraction and transport of fossil fuel. for 2030 and beyond.
million of Fiscal Year 2013 funds ( FTA-2014-001-TRI ) for the deployment of low- or no-emission (LoNo) transit buses. The program gives priority consideration to the deployment of buses with the lowest energy consumption and least harmful emissions, including direct carbon emissions. Of that amount, $21.6 7407(d)); or.
Freight transportation is a pillar of the US national economy, but while long-haul trucks account for less than 6% of the vehicle miles traveled over US highways, they account for about 40% of the emissions of air polluting particulate matter and about 55% of nitrogen oxides, the precursor to ozone in the atmosphere, the study said.
Comparison of annual N 2 O ODP-weighted emissions from the 1990s with emissions of other ODS in 1987 and in 2008. Even at the height of ODS emissions in the 1980s, annual anthropogenic N 2 O emissions were the fourth most significant. About one-third of global nitrous oxide emissions are from human activities.
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.
Illustration of projected ozone changes in the South Coast region due to climate change in 2050. Areas in orange and red could see ozone concentrations elevated by 9 to 18 parts per billion. These narrow-focused models utilize high-resolution information about the geography, meteorology and emissions of these areas.
As California continues to reduce local sources of ozone, ozone entering the state from the Pacific makes up a larger fraction of measured ozone levels. An ozonesonde is a balloon which measures ozone from the surface to more than 10 kilometers above the ground.
States covered by the proposed Transport Rule. The US Environmental Protection Agency (EPA) is proposing regulations employing the “good neighbor” provision of the Clean Air Act to reduce interstate transport of upwind state emissions from power generation that contribute to air quality problems in downwind states.
However, emissions do not just remain in conurbations; particles and gaseous pollutants can be transported thousands of kilometers by the wind. A total of approximately 100 flight hours are planned for the measurement flights in the emission plumes of Asian cities, said John P. HALO in-hangar in Taiwan.
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.
EPA’s TAG program aims to reduce air pollution in areas of the nation with the highest levels of ambient ozone and fine particulate matter (PM 2.5 ) pollution. Last year, Hyundai Motor also announced its NorCal Zero project, also known as Zero-Emission Regional Truck Operations with Fuel Cell Electric Trucks. Earlier post.)
Transport Rule states. The US Environmental Protection Agency (EPA) has finalized the new Cross-State Air Pollution Rule (CSAPR) (also called the Transport Rule). The rule will improve air quality by cutting SO 2 and NO x emissions that contribute to pollution problems in other states. NO x emissions will drop by 54%.
The California Air Resources Board (ARB) issued a grant solicitation for demonstration projects on zero-emission off-road equipment. Off-road equipment is a significant source of diesel PM, as well as NO x emissions that lead to ozone and secondary PM, ARB noted.
A new report prepared by the World Bank at the request of the G8 identifies ways that the World Bank can do more through its projects to reduce the emission of short-lived climate pollutants (SLCPs): black carbon, methane, tropospheric ozone, and fluorinated gases known as HFCs. Transportation projects. degrees Celsius.
Researchers at Tohoku University in Japan have identified a way to reduce harmful NO emissions produced by ammonia fuel during combustion. Although the space and time-averaged emission (STAE) of NO was found to decrease with increase in the global equivalence ratio (global ?) Copyright : Taylor & Francis.
A new study by researchers at MIT has found that factoring the non-CO 2 combustion emissions and effects into the lifecycle of a Synthetic Paraffinic Kerosene (SPK) aviation fuel can lead to a decrease in the relative environmental merit of the SPK fuel compared to conventional jet fuel. Aviation climate change impacts pathway.
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.
A team from Duke University in the US and University of York in the UK have utilized a novel method to estimate long-term ozone exposure and previously reported epidemiological results to quantify the health burden from long-term ozone exposure in three major regions of the world. —Karl Seltzer. Karl M Seltzer et al.
Hydrous ethanol has been used in the United States as a transportation fuel for at least one hundred years. These distilleries made 192-proof alcohol for human consumption, lantern fuel and transportation fuel. Use of Hydrous Ethanol in the United States. This moonshine was hydrous ethanol. Pursuant to 40 CFR § 80.27(a)(2):
In its recently released Inventory of US Greenhouse Gas Emissions and Sinks: 1990 – 2011 ( earlier post ), the US Environmental Protection Agency (EPA) reported that methane (CH 4 ) emissions from the field production of natural gas have declined by 36% from 2007 to 2011 (from 83.1 CH 4 emissions represented 8.8%
Ozone pollution near Earth’s surface is one of the main ingredients of summertime smog. It is also not directly measurable from space due to the abundance of ozone higher in the atmosphere, which obscures measurements of surface ozone. —Jin et al.
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