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EPA initiates new review of the Ozone National Ambient Air Quality Standards

Green Car Congress

The Environmental Protection Agency (EPA) announced a new review of the Ozone National Ambient Air Quality Standards (NAAQS). EPA established the current standards at a level of 70 parts per billion in 2015 and retained them in 2020, after concluding that there was little new information to suggest the need for revision.

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York study: Less traffic in first UK lockdown reduced NO2 pollution but caused increase in surface ozone

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Less traffic on the roads during the first COVID-19 lockdown in the UK led to a reduction in air pollution but may have caused potentially damaging surface ozone levels to rise, according to a new study led by researchers at the University of York. The problem is being created by the change in chemistry between NO x and O 3.

Ozone 397
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Study finds COVID-19 lockdown in China brought only slight reduction in PM2.5 and ozone

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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.

Ozone 243
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EPA proposes tightening primary ozone standards to range of 65-70 ppb; final rule by October 2015

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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 ppbā€”and preferably below 70 ppb.

Ozone 273
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Satellite method provides insight into ozone-NOx-VOCs sensitivity for different locations

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Ozone pollution near Earthā€™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.

Ozone 150
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Study finds that unregulated VSLS efficient at influencing climate through depletion of stratospheric ozone

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Although halogens released from long-lived anthropogenic substances, such as chlorofluorocarbons (CFCs), are the principal cause of the recent depletion of stratospheric ozone, recent observations show that very short-lived substances (VSLS), with lifetimes generally under six months, are also an important source of stratospheric halogens.

Ozone 150
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Study finds some refrigerants less damaging to ozone layer can degrade to long-lived GHG CF4

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Some of the substitutes for ozone-damaging chemicals that being phased out worldwide under international agreements are themselves potent greenhouse gases and contribute to warming. Even as we move towards shorter-lived halocarbons for industrial use, during atmospheric degradation they can produce a long-lived atmospheric effect.

Ozone 150