Weather Makes a Difference: 8-hour Ozone Trends for 1997-2005 State and Local Information for EPA Region 4


Weather Makes a Difference: 8-hour
Ozone Trends for 1997-2006

State and Local Information for EPA Region 4

Alabama
Florida
Georgia
Kentucky
Mississippi
North Carolina
South Carolina
Tennessee

Composite trend for available sites in these states:

EPA Region 04 (selected sites)

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April 2007

-------
Alabama
Ozone

On average, ozone declined 6 percent between 1997 and 2006. These improvements in
ozone are in response to both state and regional reductions in NOx and VOC emissions.
The level of ozone improvement varies from site to site.

Trends for 1997-2006 for rural sites and urban areas with complete ozone and
meteorology data are presented below. Ozone season (May 1 - September 30) averages
of daily maximum 8-hour ozone were adjusted to remove the influence of year-to-year
variability in weather conditions. The dotted line shows the trend in observed values at
monitoring sites, while the solid line illustrates the underlying ozone trend after removing
the effects of weather. The solid line serves as a more accurate ozone trend for assessing
changes in emissions. Typical weather conditions are determined by averaging
conditions (e.g., temperature, humidity, etc.) for the time period presented. The
information provided is useful for reviewing the weather influence for a particular ozone
season. The solid line represents ozone levels anticipated under typical weather
conditions.

Seasonal Average 8-hour Ozone Trends

Sand Mountain, AL

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Birmingham, AL

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Montgomery, AL

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1998

2000

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Florida
Ozone

On average, ozone declined 6 percent between 1997 and 2006. These improvements in
ozone are in response to both state and regional reductions in NOx and VOC emissions.
The level of ozone improvement varies from site to site.

Trends for 1997-2006 for rural sites and urban areas with complete ozone and
meteorology data are presented below. Ozone season (May 1 - September 30) averages
of daily maximum 8-hour ozone were adjusted to remove the influence of year-to-year
variability in weather conditions. The dotted line shows the trend in observed values at
monitoring sites, while the solid line illustrates the underlying ozone trend after removing
the effects of weather. The solid line serves as a more accurate ozone trend for assessing
changes in emissions. Typical weather conditions are determined by averaging
conditions (e.g., temperature, humidity, etc.) for the time period presented. The
information provided is useful for reviewing the weather influence for a particular ozone
season. The solid line represents ozone levels anticipated under typical weather
conditions.

Seasonal Average 8-hour Ozone Trends

Tampa, FL

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Jacksonville, FL

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Miami, FL

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Orlando, FL

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Sumatra, FL

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2000

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Georgia
Ozone

On average, ozone declined 7 percent between 1997 and 2006. These improvements in
ozone are in response to both state and regional reductions in NOx and VOC emissions.
The level of ozone improvement varies from site to site.

Trends for 1997-2006 for rural sites and urban areas with complete ozone and
meteorology data are presented below. Ozone season (May 1 - September 30) averages
of daily maximum 8-hour ozone were adjusted to remove the influence of year-to-year
variability in weather conditions. The dotted line shows the trend in observed values at
monitoring sites, while the solid line illustrates the underlying ozone trend after removing
the effects of weather. The solid line serves as a more accurate ozone trend for assessing
changes in emissions. Typical weather conditions are determined by averaging
conditions (e.g., temperature, humidity, etc.) for the time period presented. The
information provided is useful for reviewing the weather influence for a particular ozone
season. The solid line represents ozone levels anticipated under typical weather
conditions.

Seasonal Average 8-hour Ozone Trends

Savannah, GA

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Atlanta, GA

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1998

2000

2002
Year

2004

2006

-------
Kentucky
Ozone

On average, ozone declined 10 percent between 1997 and 2006. These improvements in
ozone are in response to both state and regional reductions in NOx and VOC emissions.
The level of ozone improvement varies from site to site.

Trends for 1997-2006 for rural sites and urban areas with complete ozone and
meteorology data are presented below. Ozone season (May 1 - September 30) averages
of daily maximum 8-hour ozone were adjusted to remove the influence of year-to-year
variability in weather conditions. The dotted line shows the trend in observed values at
monitoring sites, while the solid line illustrates the underlying ozone trend after removing
the effects of weather. The solid line serves as a more accurate ozone trend for assessing
changes in emissions. Typical weather conditions are determined by averaging
conditions (e.g., temperature, humidity, etc.) for the time period presented. The
information provided is useful for reviewing the weather influence for a particular ozone
season. The solid line represents ozone levels anticipated under typical weather
conditions.

Seasonal Average 8-hour Ozone Trends

Louisville, KY

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Cadiz, KY

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Crockett, KY

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Lexington, KY

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Mississippi
Ozone

On average, ozone declined 16 percent between 1997 and 2006. These improvements in
ozone are in response to both state and regional reductions in NOx and VOC emissions.
The level of ozone improvement varies from site to site.

Trends for 1997-2006 for rural sites and urban areas with complete ozone and
meteorology data are presented below. Ozone season (May 1 - September 30) averages
of daily maximum 8-hour ozone were adjusted to remove the influence of year-to-year
variability in weather conditions. The dotted line shows the trend in observed values at
monitoring sites, while the solid line illustrates the underlying ozone trend after removing
the effects of weather. The solid line serves as a more accurate ozone trend for assessing
changes in emissions. Typical weather conditions are determined by averaging
conditions (e.g., temperature, humidity, etc.) for the time period presented. The
information provided is useful for reviewing the weather influence for a particular ozone
season. The solid line represents ozone levels anticipated under typical weather
conditions.

Seasonal Average 8-hour Ozone Trends

Jackson, MS

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North Carolina
Ozone

On average, ozone declined 12 percent between 1997 and 2006. These improvements in
ozone are in response to both state and regional reductions in NOx and VOC emissions.
The level of ozone improvement varies from site to site.

Trends for 1997-2006 for rural sites and urban areas with complete ozone and
meteorology data are presented below. Ozone season (May 1 - September 30) averages
of daily maximum 8-hour ozone were adjusted to remove the influence of year-to-year
variability in weather conditions. The dotted line shows the trend in observed values at
monitoring sites, while the solid line illustrates the underlying ozone trend after removing
the effects of weather. The solid line serves as a more accurate ozone trend for assessing
changes in emissions. Typical weather conditions are determined by averaging
conditions (e.g., temperature, humidity, etc.) for the time period presented. The
information provided is useful for reviewing the weather influence for a particular ozone
season. The solid line represents ozone levels anticipated under typical weather
conditions.

Seasonal Average 8-hour Ozone Trends

Raleigh, NC

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Beaufort, NC

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Charllotte, NC

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Candor, NC

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Coweeta, NC

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Greensboro, NC

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Cranberry, NC

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-------
South Carolina
Ozone

On average, ozone did not change between 1997 and 2006. There have been
improvements in Columbia and Greenville in recent years. These improvements in ozone
are in response to both state and regional reductions in NOx and VOC emissions. Ozone
trends vary from site to site.

Trends for 1997-2006 for rural sites and urban areas with complete ozone and
meteorology data are presented below. Ozone season (May 1 - September 30) averages
of daily maximum 8-hour ozone were adjusted to remove the influence of year-to-year
variability in weather conditions. The dotted line shows the trend in observed values at
monitoring sites, while the solid line illustrates the underlying ozone trend after removing
the effects of weather. The solid line serves as a more accurate ozone trend for assessing
changes in emissions. Typical weather conditions are determined by averaging
conditions (e.g., temperature, humidity, etc.) for the time period presented. The
information provided is useful for reviewing the weather influence for a particular ozone
season. The solid line represents ozone levels anticipated under typical weather
conditions.

Seasonal Average 8-hour Ozone Trends

Greenville, SC

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Charleston, SC

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Tennessee
Ozone

On average, ozone declined 10 percent between 1997 and 2006. These improvements in
ozone are in response to both state and regional reductions in NOx and VOC emissions.
The level of ozone improvement varies from site to site.

Trends for 1997-2006 for rural sites and urban areas with complete ozone and
meteorology data are presented below. Ozone season (May 1 - September 30) averages
of daily maximum 8-hour ozone were adjusted to remove the influence of year-to-year
variability in weather conditions. The dotted line shows the trend in observed values at
monitoring sites, while the solid line illustrates the underlying ozone trend after removing
the effects of weather. The solid line serves as a more accurate ozone trend for assessing
changes in emissions. Typical weather conditions are determined by averaging
conditions (e.g., temperature, humidity, etc.) for the time period presented. The
information provided is useful for reviewing the weather influence for a particular ozone
season. The solid line represents ozone levels anticipated under typical weather
conditions.

Seasonal Average 8-hour Ozone Trends

Speedwell, TN

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Chattanooga, TN

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Edgar Evins, TN

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Knoxville, TN

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Memphis, TN

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1998

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-------
Nashville, TN

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