This site uses cookies to improve your experience. To help us insure we adhere to various privacy regulations, please select your country/region of residence. If you do not select a country, we will assume you are from the United States. Select your Cookie Settings or view our Privacy Policy and Terms of Use.
Cookie Settings
Cookies and similar technologies are used on this website for proper function of the website, for tracking performance analytics and for marketing purposes. We and some of our third-party providers may use cookie data for various purposes. Please review the cookie settings below and choose your preference.
Used for the proper function of the website
Used for monitoring website traffic and interactions
Cookie Settings
Cookies and similar technologies are used on this website for proper function of the website, for tracking performance analytics and for marketing purposes. We and some of our third-party providers may use cookie data for various purposes. Please review the cookie settings below and choose your preference.
Strictly Necessary: Used for the proper function of the website
Performance/Analytics: Used for monitoring website traffic and interactions
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.
In a statement released this morning, President Barack Obama said he has requested that US Environmental Protection Agency (EPA) Administrator Lisa Jackson withdraw the agency’s draft Ozone National Ambient Air Quality Standards (NAAQS) rulemaking. Earlier post.) National Ambient Air Quality Standards (NAAQS).
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.
Levels of two major air pollutants have been reduced significantly since lockdowns began in response to the COVID-19 pandemic, but a secondary pollutant—ground-level ozone—has increased in China, according to new research. Ozone is harmful to humans at ground-level, causing pulmonary and heart disease. —Guy Brasseur.
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.
A new study led by researchers at the University of North Carolina at Chapel Hill has found that deaths related to air pollution in the US were nearly halved between 1990 and 2010. and ozone from a 21-year computer simulation of air pollution across the US. Trends in the total mortality burden (black) for PM 2.5 (a, and Wong, D.
The US Environmental Protection Agency (EPA) has announced two final rules that will further reduce the availability and use of hydrochlorofluorocarbons (HCFCs), which are primarily used as refrigerants and harm the ozone layer. The 2010 HCFC Regulations.
A study by an international team led by scientists at the University of East Anglia have identified four new man-made gases in the atmosphere, all of which are contributing to the destruction of the ozone layer. CFCs are the main cause of the hole in the ozone layer over Antarctica. Brenninkmeijer, Paul J. Oram, Claire E.
Extraordinarily cold temperatures in the stratosphere during the winter of 2010/2011 caused the most massive destruction of the ozone layer above the Arctic so far, according to a study by climate researchers at KIT (Karlsruhe Institute of Technology). These chemical conversion products attack the ozone layer and destroy it partly.
The US Environmental Protection Agency (EPA) will reconsider the 2008 primary and secondary ozone standards. In 2008, EPA established a new primary 8-hour standard for ozone of 0.075 parts per million (ppm), and a new secondary standard set at a form and level identical to the new primary standard. ppm standard, due to rounding.
US EPA Region 9 8-hour ozone trends, 1979-2000. These State Implementation Plans (SIPs) are the roadmaps to meeting the 1997 8-hour ozone National Ambient Air Quality Standards (NAAQS) of 0.08 In 1997, EPA first established the 8-hour ozone standard, which replaced the older 1-hour ozone standard (0.12 Source: EPA.
Counties projected to violate proposed Primary 8-hour Ground-Level Ozone Standards in 2020. The United States Environmental Protection Agency has proposed the strictest standards to date for ground-level ozone. EPA is proposing an accelerated schedule for designating areas for the primary ozone standard. 2010 in Arlington, Va.
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.
in 2010—i.e., It also includes several chemicals known to deplete Earth’s protective ozone layer, which are also active as greenhouse gases. A continued recent increase in methane: Methane levels rose in 2010 for the fourth consecutive year after remaining nearly constant for the preceding 10 years, up to 1799 parts per billion.
In a new study published online 10 March in the ACS journal Environmental Science and Technology , however, Stanford University professor Mark Jacobson finds that local CO 2 emissions in isolation may increase local ozone and particulate matter. Jacobson, 2010. Jacobson (2010) Enhancement of Local Air Pollution by Urban CO 2 Domes.
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. —NOAA scientist Stephen Montzka, lead author of the paper.
Denver represents an interesting case study for exploring potential PHEV impacts because it violates the federal air quality standard for ozone and because several large EGUs [electricity generating units] are located in or near the urbanized area. Ozone concentration increases were modeled for small areas near central Denver.
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. Click to enlarge. These narrow-focused models utilize high-resolution information about the geography, meteorology and emissions of these areas.
A scatter plot of CO, as a tracer for pollution, versus CO 2 , as a tracer for the amount of combustion, for 2002 and 2010. Even though the CO 2 enhancements over background were comparable in the two years, about 25 ppm in 2002 and 35 ppm in 2010, the ?CO/?CO2 CO2 ratio for this flight track segment decreased from 24.5
The amount of greenhouse gases in the atmosphere reached a new high in 2010 since pre-industrial time and the rate of increase has accelerated, according to the World Meteorological Organization’s (WMO) Greenhouse Gas Bulletin. Between 2009 and 2010, its atmospheric abundance increased by 2.3 parts per million) and the past decade (2.0
The Environmental Protection Agency (EPA) announced a new review of the Ozone National Ambient Air Quality Standards (NAAQS). In October 2021, EPA announced a reconsideration of the previous Administration’s decision to retain the NAAQS for ozone. In many of the areas designated as not meeting the current 2015 standards, work remains.
55% of land area) by the middle of the century, and would increase by 3% and 4% the population-weighted average concentrations of fine particulate matter (PM 2.5 ) and ozone, respectively. and ozone exposure, respectively. and ozone in 2050 by factors of 1 and 3, respectively. C) and ozone (D) exposure are shown.
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.
Lisa P Jackson, Administrator of the US Environmental Protection Agency, issued a public memo to EPA employees detaling “ seven key themes to focus the work of our agency ” in 2010 and beyond. The seven themes are: Taking Action on Climate Change. Improving Air Quality.
The total estimated funding for this competitive opportunity for FY 2009/2010 is approximately $64 million, including all non-tribal and tribal awards. million tons of NO x , which contribute to the formation of ozone and additional fine particles.
2010 engines emissions reduction relative to 2010, 2007, and 2004 US emission standards. earlier post ), found that emissions of NO 2 and other nitrogen oxides—which can have direct health effects and contribute to the formation of smog—were approximately 61% below the 2010 EPA standard and 99% lower than in 2004 engines.
In addition to studying the important issues at the nexus of the air quality and climate change problems, the goal of CalNex 2010 is also to provide scientific information regarding the trade-offs faced by decision makers when addressing these two inter-related issues. 2010 CalNex Science and Implementation Plan. emission inventories?
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. García-Cubero et al.
State level ozone emissions in the NBP, from 1990 to 2010 (projected). This market-based cap and trade program was created to cost-effectively reduce NO x emissions during the ozone season. Source: EPA. Click to enlarge.
Surabi Menon, Hashem Akbari, Sarith Mahanama, Igor Sednev and Ronnen Levinson (2010) Radiative forcing and temperature response to changes in urban albedos and associated CO 2 offsets. 5 014005 doi: 10.1088/1748-9326/5/1/01400.
The team used a population-weighted multi pollutant index (PW-MPI), suited for global model output, with the atmospheric chemistry general circulation model EMAC to estimate the impact of anthropogenic emission changes on global and regional air quality in recent and future years (2005, 2010, 2025 and 2050).
The process was presented during the 90 th Springtime Annual Meeting of The Chemical Society of Japan (CSJ), 26-29 March, 2010. Unlike other ethers, DME does not form peroxides, is non-toxic, has no effect on global warming nor ozone depletion and can be considered an environmentally friendly solvent.
Data collected during a major 2010 state-federal atmospheric research project show that the first-in-the-nation regulation requiring ocean-going vessels to use clean fuel when near the California coast has been extremely effective in reducing sulfur dioxide pollution from ships, according to the California Air Resources Board (ARB).
Compared to the 2010 “Business as Usual” scenario—which includes all adopted emission control measures for the South Coast—NO x levels must be reduced by 65% and by 75% to meet the 2023 and 2032 ozone standards, respectively. An 80% reduction of GHG emissions is targeted for 2050, relative to 1990 levels.
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. A snapshot from a simulation of how Bakken oil field hydrocarbon emissions including ethane affect North American ground-level ozone concentrations.
Global and regional zonal mean temperature changes relative to 2010 due to non-CO 2. million metric tons of avoided ozone-related yield losses of major food crops; $US0.6-2.4 That’s largely because more stringent standards would reduce emissions of black carbon, a constituent of soot, and carbon monoxide, a precursor of ozone.
used a climate model to analyze the effects of a wide range of chemical species, including carbon dioxide, nitrous oxide, methane, organic carbon, black carbon, nitrate, sulfate, and ozone, from 13 sectors of the economy from 2000 to 2100. Bauer (2010) Attribution of climate forcing to economic sectors. Unger et al. A hat-tip to Tom!).
Climate change due to emission of greenhouse gases from fossil fuel energy sources causes air pollution by increasing ground-level ozone and concentrations of fine particulate matter. Black carbon is a short-lived greenhouse pollutant which, along with ozone, is responsible for a significant proportion of global warming.
The US Environmental Protection Agency (EPA) has designated the five-county Philadelphia region of Bucks, Delaware, Chester, Montgomery and Philadelphia counties as non-attainment for ozone and fine particulate matter air quality standards. Berks, Lehigh and Northampton counties recently achieved attainment status for federal ozone standards.
giga tonne carbon dioxide equivalent (GtCO 2 eq) (2.2%) per year from 2000 to 2010 compared to 0.4 Total anthropogenic GHG emissions were the highest in human history from 2000 to 2010 and reached 49 (±4.5) GtCO 2 eq/yr in 2010. GtCO 2 eq (1.3%) per year from 1970 to 2000. Transport sector. Integrated urban planning, transit?oriented
NO x is a precursor for both ground level ozone and secondary PM 2.5 The main conclusions of the report include: Compared to emission controls on MY 2010 US diesel trucks, today’s compact aftertreatment systems are 40% lighter, 60% smaller, and substantially less expensive.
Evaporative emissions from gasoline—volatile organic compounds (VOCs)—are precursors to the formation of tropospheric ozone and contribute to ground-level ozone. Nielsen (2010) Vapor Pressures of Alcohol-Gasoline Blends. It is also a critical factor in meeting evaporative emission requirements. Resources. Andersen, J.
Nitrous oxide is a potent greenhouse gas that contributes to climate change and stratospheric ozone destruction. They believe that nitrous oxide is the leading human-caused threat to the atmospheric ozone layer, which protects Earth from harmful ultraviolet radiation from the Sun. Beaulieu et al. PNAS doi: 10.1073/pnas.1011464108.
USPresident Barack Obama has requested that the US Environmental Protection Agency (EPA) withdraw its Ozone National Ambient Air Quality Standards (NAAQS) rulemaking.
We organize all of the trending information in your field so you don't have to. Join 5,000+ users and stay up to date on the latest articles your peers are reading.
You know about us, now we want to get to know you!
Let's personalize your content
Let's get even more personalized
We recognize your account from another site in our network, please click 'Send Email' below to continue with verifying your account and setting a password.
Let's personalize your content