Sentences with phrase «ozone levels»

Have air quality regulations reduced ozone levels in developed nations?

This may be due to the broader geographic scale at which high ozone levels tend to present.

This video seems to suggest that actually no - one had thought to do a long term plot of ozone levels.

The burning of agricultural residue causes severe pollution in land, water and air and contributes to increased ozone levels and climate change in the long term.

The colour scale for increasing and decreasing ozone levels over time and associated p - values is the same as in Figure 8.

But as water vapor becomes present in the atmosphere, ozone levels drop.

At its worst it can help create seven more days a year when ozone levels exceed air pollution limits.

Still, arctic ozone levels fell during most winters in the 1990s, making researchers worry that a northern ozone hole might appear.

Even short periods of unhealthy ozone levels can cause local death rates to rise.

Overall, CO2 and methane tend to increase global ozone levels.

Model predictions show that ozone levels tend to be highest in regions where crops are grown.

We find robust evidence that ozone levels well below federal air quality standards have a significant impact on productivity.

For all three regions, the figures for the past two winter - spring seasons are the lowest ever observed, and statistically well below the mean ozone level in these areas.

Outside polar regions, where chemical ozone destruction is less pronounced but potentially harmful to human health, it appears as if ozone levels are beginning to increase.

He also noted that while ozone levels have gone down, asthma has continued to go up.

They found that elevated CO2 of 800 ppm, increased pollen production per flower by 53 percent while the different ozone levels had no effect on the amount of pollen produced.

The study also found that satellite measurements could be used as an early warning system to alert policy makers to incoming ozone levels one to three days ahead of time.

The process can reverse at night, meaning ozone levels near the surface often vary greatly during a single day.

A new study has revealed that ozone levels in the heavily populated lower latitudes don't seem to be recovering as well as regions near the poles.

Oil and gas development has long drawn criticism for its environmental effects, which range from road - killed wildlife to unhealthy ozone levels.

Generally, ozone levels tend to be lower in the morning.

A York University (Toronto) professor made a presentation on ozone levels over Toronto.

Lower ozone levels in the stratosphere may result in more skin cancers, cataracts, and may result in higher incidence of certain diseases.

That agrees remarkably well with the roughly 15 % increase the researchers had predicted based on the known decline in stratospheric ozone levels measured since 1978 in Lauder.

The image was produced using a computer model which estimates ozone levels from actual meteorological data.

Recent increases in an unregulated ozone - depleting substance, could delay recovery of Antarctic ozone levels by 5 - 30 years, depending on emissions scenarios.

Elisabetta Pierazzo of the Planetary Science Institute in Tucson, Arizona, and colleagues used a global climate model to study how water vapour and sea salt thrown up from an impact will affect ozone levels for years after the event.

These findings further suggest reduced exposure to high levels of ozone in parts of North America and Europe, but increased exposure to moderate to high ozone levels at a small proportion of urban locations, although many sites in these two regions have non-significant trends.

The study explains why springtime ozone levels measured in Yellowstone National Park and other western parks far from urban areas have climbed over the past quarter century.

Shown are the 1988 - 2014trends in springtime ozone levels on days that were very smoggy (top panel) and of average smogginess (bottom panel), from observations (left) and from a model built by the Geophysical Fluid Dynamics Laboratory (right).

«Ozone recovery may be delayed by unregulated chemicals: Recent increases in an unregulated ozone - depleting substance, could delay recovery of Antarctic ozone levels by 5 - 30 years, depending on emissions scenarios.»

EPA data shows ozone levels declined 18 percent between 2008 and 2013.

Zatko and her adviser at the University of Washington in Seattle realized she could join an ongoing research project in Utah that was studying causes of the area's unusually high ozone levels during winter.

A Northwestern University study by an economist and a chemist reports that when fuel prices drove residents of São Paulo, Brazil, to mostly switch from ethanol to gasoline in their flexible - fuel vehicles, local ozone levels dropped 20 percent.

But this study suggests that repeated exposures to elevated ozone levels over time have cumulative effects on respiratory health.»

«With our hot, dry summers, we tend to see higher ozone levels because ozone is formed with a combination of air pollution and sunlight.

So Kramarova took a closer look at data gathered by the Suomi National Polar - orbiting Partnership satellite, which showed ozone levels with altitude.

Ozone was recorded at 160 micrograms per cubic metre, a level considered moderate - to - high on the UK's pollution index and almost twice as high as Aberdeen, which had the UK's worst ozone levels at time of writing.

The results for South Korea and Hong Kong indicate that both the high peaks and the mid-high ozone levels have increased in East Asia during 2000 — 2014, whilst the situation for Japan is less clear.

decline in ozone levels between 1980 and 2007.

Arctic ozone levels exhibit high natural seasonal and interannual variability, however, driven primarily by atmospheric dynamics; and between 1979 and 2000, the trend in mean annual total column ozone over the Arctic was about − 3 % per decade (7 % accumulated loss)(29).

While at least part of the problem is environmental (blame decreasing ozone levels), the main risk for melanoma arises from individual predisposition and behavior.

The QBO entered its easterly phase at higher altitudes, 1.5 hPa zonal winds decreased sharply, NH polar ozone levels around 45 km increased while the same region saw a drop in temperature, the AO went negative with an abrupt change in jet stream behavior that Europe is now witnessing via some fairly brutal weather.

It found that ozone levels above western North America creep upward every spring.