Sentences with phrase «ozone concentrations by»

The researchers calculated that adopting GHG mitigation technologies would reduce particulate matter and ambient ozone concentrations by about 10 percent.

This thinning, which can decrease the ozone concentration by as much as 70 percent, was caused by the rampant use of human - made chlorofluorocarbons (CFCs), organic compounds that were once widely used in cooling systems and aerosols.

Not exact matches

In this study in Timothy grass, researchers led by environmental health scientist Christine Rogers of the UMass Amherst School of Public Health and Health Sciences (SPHHS) determined the interactive effects of CO2 and ozone at projected higher levels on pollen production and concentrations of a Timothy grass pollen protein that is a major human allergen.

Sunbelt cities like Los Angeles, Riverside, Calif., and Houston, with their seemingly endless sunny days, gridlocked urban sprawl and heat - trapping stagnant air masses, contain the highest average concentrations of ozone, according to a 2009 study by University of California, Berkeley scientists.

Gary Cohen, president and founder of the Massachusetts - based nonprofit Health Care Without Harm, said in a telephone interview that the risks of climate change to both the health of U.S. citizens and the U.S. health care delivery system is profound, particularly in urban areas, where warming average temperatures are exacerbated by the heat island effect and high concentrations of other air pollution like ozone and particulate matter.

By adjusting elements of the test, such as the air exchange rate, which is the number of times per hour indoor air is replaced by outdoor air, as well as the concentrations of terpene and ozone in the chamber, the group was able to ascertain how those variables each affected the formation of secondary organic aerosolBy adjusting elements of the test, such as the air exchange rate, which is the number of times per hour indoor air is replaced by outdoor air, as well as the concentrations of terpene and ozone in the chamber, the group was able to ascertain how those variables each affected the formation of secondary organic aerosolby outdoor air, as well as the concentrations of terpene and ozone in the chamber, the group was able to ascertain how those variables each affected the formation of secondary organic aerosols.

These air temperature reductions have also been projected to improve local air quality by reducing smog formation and ozone concentration.

«Wave patterns in the images, revealed by UV absorption from ozone concentrations, are critical to understanding the wind patterns, giving scientists an additional means to study the chemistry and global circulation of the atmosphere,» writes NASA.

Increased incidence of cardio - respiratory diseases caused by higher concentrations of ground - level ozone (smog) is projected.

Pallas is one of the sites of the Finnish network for monitoring the concentrations of mercury and other heavy metals, benzo (a) pyrene, ozone and other air pollutants, as required by the European legislation on ambient air quality.

This line from the abstract of an important paper in Science papers in 1974 says much: «Calculations indicate that chlorofluoromethanes produced by man can greatly affect the concentrations of stratospheric ozone in future decades.»

Of course, though some of the flux up at the tropopause escapes directly to space, and some is absorbed by CO2 (over the whole stratosphere in the wings of the CO2 band, concentrated towards the base of the stratosphere for larger optical thicknesses), some is absorbed by ozone (with variable concentration), and some by water vapor.

As to the specific papers you cited, Miller et al 2006 states,» Recent changes in the magnitude of the annular patterns have been interpreted as the signature of anthropogenic forcing by changes in the concentration of greenhouse gases (GHGs) or else stratospheric ozone [Shindell et al., 1999; Fyfe et al., 1999; Kushner et al., 2001; Kindem and Christiansen, 2001; Sexton, 2001; Gillett and Thompson, 2003; Shindell and Schmidt, 2004; Arblaster and Meehl, 2006].»

There certainly isn't such a cycle in the GHG concentrations, and while it's conceivable that the ozone runs used an ozone field that was modulated by solar activity, I doubt that this was the case (that kind of simulation is only just being to be made).

Adding sulfur to the statosphere would do some real serious direct or indirect chemical chain reactions, already known by past volcanic events, when stratospheric Ozone concentrations dip after strong eruptions.

# 157, Alastair, I am not keen on Tropopause heights because they cause a warming below, it is rather tropopause heights are higher because it is warmer below, there is also tropopause inversions triggered by higher Ozone concentrations, at the point where the tropopause starts you will invariably find the beginning of much higher ozone concentratOzone concentrations, at the point where the tropopause starts you will invariably find the beginning of much higher ozone concentratozone concentrations.

The Imperial College London researchers cautioned that even plants that can take advantage of higher CO2 levels could be harmed by other climate change impacts, such as increased temperature and ozone concentration.

Pallas is one of the sites of the Finnish network for monitoring the concentrations of mercury and other heavy metals, benzo (a) pyrene, ozone and other air pollutants, as required by the European legislation on ambient air quality.

Their central estimate suggests that a 10 ppb (parts per billion) decrease in ozone concentration increases worker productivity by 4.2 percent.

During the period of summer ozone recovery (2000 — 2050), the SAM index exhibits weakly negative, statistically insignificant trends due to stratospheric ozone recovery which offsets the positive forcing imposed by increasing GHG concentrations.

By increasing these different factors, climate change is projected to lead to increased concentrations of ozone and particulate matter in some regions.

The change in total solar irradiance over recent 11 - year sunspot cycles amounts to < 0.1 %, but greater changes at ultraviolet wavelengths may have substantial impacts on stratospheric ozone concentrations, thereby altering both stratospheric and tropospheric circulation patterns... This model prediction is supported by paleoclimatic proxy reconstructions over the past millennium.

Icelandic volcanoes are about 30 degrees away from the pole, too far except for the strongest eruptions, to be swept - up (in suficient enough concentration) into the stratosphere by polar vortex, hence the ozone layer there is more stable, despite fact there was more CFC around in the Nth than Sth hemisphere.

Halogenated gases currently contribute 12 % to overall radiative forcing.1 While actions under the Montreal Protocol on Substances that Deplete the Ozone Layer (Montreal Protocol) are already addressing CFCs and HCFCs, atmospheric concentrations of some HFCs (hydrofluorocarbons) are rising rapidly, by more than 23 % each year.

As a result of the discovery of ozone depletion and the scientific advances that delineated its causes, efforts to reduce the production, and ultimately the atmospheric concentrations, of ozone - depleting chemicals were begun in the late 1980s through the ratification of the Montreal Protocol on Substances that Deplete the Ozone Layer by many countries across the gozone depletion and the scientific advances that delineated its causes, efforts to reduce the production, and ultimately the atmospheric concentrations, of ozone - depleting chemicals were begun in the late 1980s through the ratification of the Montreal Protocol on Substances that Deplete the Ozone Layer by many countries across the gozone - depleting chemicals were begun in the late 1980s through the ratification of the Montreal Protocol on Substances that Deplete the Ozone Layer by many countries across the gOzone Layer by many countries across the globe.

By knowing the volume flow rate and temperature, the electrical current can be converted to an ozone concentration under the assumption that the ozone reaction with potassium iodide is quantitatively known.

This study of course does not take away very different concerns related to stratospheric aerosol SRM geoengineering, like possible damage to the ozone layer [which in turn would be good news if you hate waiting for that spring tan] and the fact that allowing CO2 concentrations to keep rising presents other problems, like the necessity to never stop with the active process of SRM geoengineering, and increasing ecological damage caused by ocean acidification.

At the same time, increased use of domestic natural gas has helped reduce ozone concentrations in the air by 17 percent since 2005:

«The direct health effects caused by higher ozone concentration include irritation of mucous membranes, respiratory reactions such as reduced lung functions, cardiovascular diseases, as well as an impaired physical performance,» according to Umweltbundesamt.

If ozone was been mainly formed by the conventional Chapman mechanism, then there is no reason why the ozone concentrations should be correlated to the phase change conditions.

The progress we've made is undeniable - national average peak ozone concentrations have dropped by 17 percent since 2000.

Since a sustainable future based on the continued extraction of coal, oil and gas in the «business - as - usual mode» will not be possible because of both resource depletion and environmental damages (as caused, e.g., by dangerous sea level rise) we urge our societies to -LSB-...] Reduce the concentrations of warming air pollutants (dark soot, methane, lower atmosphere ozone, and hydrofluorocarbons) by as much as 50 % [and] cut the climate forcers that have short atmospheric lifetimes.

7 Global Warming An increase in global temperatures due to increases in the concentrations of greenhouse gases Increased CO 2 concentrations exerts largest radiative forcing (i.e., explains bulk of temperature increase) NOT CAUSED BY STRATOSPHERIC OZONE DEPLETION

Simply put, stratospheric temperature is maintained by concentrations of ozone.

Ozone is present in the stratosphere and has actually been depleted in the recent past by human use of CFC gases, but there is no anthropogenic process likely to add to stratospheric ozone concentraOzone is present in the stratosphere and has actually been depleted in the recent past by human use of CFC gases, but there is no anthropogenic process likely to add to stratospheric ozone concentraozone concentration.

Ozone is formed from dioxygen by the action of ultraviolet light and also atmospheric electrical discharges, and is present in low concentrations throughout the Earth's atmosphere.

TSIS, ERBS, and OMPS - Limb measure, respectively, the incoming solar energy, the energy reflected and emitted by Earth, and the height - dependent concentration of atmospheric ozone that modulates these energy fluxes.

Changes in stratospheric temperatures, induced by changes in ozone or LLGHG concentration, alter the Brewer - Dobson circulation (Butchart and Scaife, 2001; Butchart et al., 2006), controlling the rate at which long - lived molecules, such as LLGHGs, CFCs, HCFCs and halogens are transported from the troposphere to various levels in the stratosphere.

Since a large body of evidence links pollution with poor health, and health is an important part of human capital, efforts to reduce pollution could plausibly be viewed as an investment in human capital and thus a tool for promoting economic growth... We find robust evidence that ozone levels well below federal air quality standards have a significant impact on productivity: a 10 ppb decrease in ozone concentrations increases worker productivity by 4.2 percent.

«Thanks in part to the increased use of domestic natural gas, ozone concentrations in the air have dropped by 17 percent since 2000, all of which makes the United States not just an energy superpower, but also a leader in reducing global emissions.