11

Asheville Air QualityAsheville Air Quality

Megan StoneMegan Stone

22

Clean Smokestacks ActClean Smokestacks Act

Passed in 2002 by the General Assembly of Passed in 2002 by the General Assembly of North CarolinaNorth Carolina

““An act to improve air quality in the state by An act to improve air quality in the state by imposing limits on the emission of certain imposing limits on the emission of certain pollutants from certain facilities that burn coal pollutants from certain facilities that burn coal to generate electricity…”to generate electricity…”

33

Clean Smokestacks ActClean Smokestacks Act

Requires Progress Energy and Duke Energy to Requires Progress Energy and Duke Energy to submit annual reports containing air quality submit annual reports containing air quality information.information.

Progress Energy has spent $190 million dollars Progress Energy has spent $190 million dollars at the Asheville plant for technologies to at the Asheville plant for technologies to reduce emissions.reduce emissions.

44

Clean Smokestacks ActClean Smokestacks Act Western North Carolina Western North Carolina

has a huge ozone has a huge ozone problem.problem.

Cutting NOx emissions Cutting NOx emissions would reduce the amount would reduce the amount of ozone in the area. of ozone in the area.

Scrubbers have been Scrubbers have been installed in the Asheville installed in the Asheville Power PlantPower Plant

55

Formation of OzoneFormation of Ozone

66

ScrubbersScrubbers

NOx + NOx + NHNH44 H H22O(g) + NO(g) + N22

77

7 Day Running Average (1HR)

0.000

0.010

0.020

0.030

0.040

0.050

0.060

0.070

0.080

0.0904/

1/20

04

4/29

/200

4

5/27

/200

4

6/24

/200

4

7/22

/200

4

8/19

/200

4

9/16

/200

4

10/1

4/20

04

4/11

/200

5

5/9/

2005

6/6/

2005

7/4/

2005

8/1/

2005

8/29

/200

5

9/26

/200

5

10/2

4/20

05

4/21

/200

6

5/19

/200

6

6/16

/200

6

7/14

/200

6

8/11

/200

6

9/8/

2006

10/6

/200

6

4/3/

2007

5/1/

2007

5/29

/200

7

6/26

/200

7

7/24

/200

7

8/21

/200

7

9/18

/200

7

10/1

6/20

07

2004-2006

Ozo

ne(

PP

M)

Summer 2004 Summer 2005 Summer 2006

SCR #1 installedJune 14, 2006

Summer 2007

SCR #2 installedMay 7, 2007

88

Ozone Summer 1HR Average 1998-2005

y = -9E-06x + 0.0636

0.000

0.020

0.040

0.060

0.080

0.100

0.120

0.14001

-Apr

-98

28-M

ay-9

8

24-J

ul-9

8

19-S

ep-9

8

9/M

ay/9

9

5/Ju

l/99

31/A

ug/9

9

27/O

ct/9

9

5/23

/200

0

7/19

/200

0

9/14

/200

0

4/10

/200

1

6/6/

2001

8/2/

2001

9/28

/200

1

4/24

/200

2

6/20

/200

2

8/16

/200

2

10/1

2/20

02

5/8/

2003

7/4/

2003

8/30

/200

3

10/2

6/20

03

5/22

/200

4

7/18

/200

4

9/13

/200

4

4/9/

2005

6/5/

2005

8/1/

2005

9/27

/200

5

Date

Ozo

ne

(pp

m)

99

Ozone Summer 1HR Average 1998-2006

y = -5E-06x + 0.0609

0.000

0.020

0.040

0.060

0.080

0.100

0.120

0.14001

-Apr

-98

11-J

un-9

8

21-A

ug-9

8

31-O

ct-9

8

4/Ju

l/99

13/S

ep/9

9

4/23

/200

0

7/3/

2000

9/12

/200

0

4/22

/200

1

7/2/

2001

9/11

/200

1

4/21

/200

2

7/1/

2002

9/10

/200

2

4/20

/200

3

6/30

/200

3

9/9/

2003

4/19

/200

4

6/29

/200

4

9/8/

2004

4/18

/200

5

6/28

/200

5

9/7/

2005

4/17

/200

6

6/27

/200

6

9/6/

2006

4/16

/200

7

6/26

/200

7

9/5/

2007

Date

Ozo

ne(

PP

M)

1010

Correlation CoefficientCorrelation Coefficient

Measures the linear relationship between two Measures the linear relationship between two variables.variables.

The correlation coefficient (rThe correlation coefficient (r22) is always ) is always between -1 and +1. The closer the correlation between -1 and +1. The closer the correlation is to +/-1, the closer to a perfect linear is to +/-1, the closer to a perfect linear relationship. relationship.

1111

Correlation CoefficientCorrelation Coefficient

Ozone vs. SunlightOzone vs. Sunlight

Ozone vs. VOCsOzone vs. VOCs

Ozone vs. NOxOzone vs. NOx

1212

Sunlight vs. OzoneSunlight vs. Ozone

HypothesisHypothesis: More sunlight yields more ozone. : More sunlight yields more ozone.

Therefore, RTherefore, R22 > 0 for a correlation between > 0 for a correlation between ozone and sunlight amount. ozone and sunlight amount.

Retrieved daily “clear” observations for Retrieved daily “clear” observations for 2006/2007 summers from NCDC 2006/2007 summers from NCDC calculated calculated daily percentages (10am, 1pm, and 4pm)daily percentages (10am, 1pm, and 4pm)

1313

2006

0

10

20

30

40

50

60

70

April May June July August September October

Month

Per

cen

tag

e

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

Month

PP

M Clear Percentage

Ozone PPM

1414

20062006

April 63.33333 0.058967

May 40.86022 0.058967

June 50 0.058333

July 50.53763 0.058581

August 38.70968 0.055032

September 36.66667 0.043087

October 61.29032 0.041065

0.012316 Monthly

Sunlight % Ozone (ppm)

1515

2007 Ozone vs. Clear Afternoons

0

10

20

30

40

50

60

70

80

April May June July August Sept Oct

Month

Per

cen

tag

e

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

PP

M Clear Afternoons

Ozone

1616

20072007

April 54.44444 0.0563

May 53.83871 0.062871

June 54.44444 0.062167

July 38.70968 0.052065

August 69.89247 0.065032

Sept 50 0.058033

Oct 51.6129 0.042931

Monthly 0.55681

Sunlight % Ozone (ppm)

1717

Sunlight vs. OzoneSunlight vs. Ozone

2006: R2006: R22 = 0.012316 = 0.012316 Practically no Practically no correlationcorrelation

2007: R2007: R22 = 0.55681 = 0.55681 Much stronger positive Much stronger positive correlationcorrelation

ConclusionConclusion: Both are positive correlations.: Both are positive correlations.

(But what happened in 2006?) (But what happened in 2006?)

1818

Ozone vs. VOCsOzone vs. VOCs

The state of NC releases estimates of how The state of NC releases estimates of how much VOCs are released by humans per much VOCs are released by humans per month every three years.month every three years.

VOCs are not monitored.VOCs are not monitored.

HypothesisHypothesis: An increase of VOCs yields an : An increase of VOCs yields an increase of ozone. Therefore, Rincrease of ozone. Therefore, R22 > 0 for a > 0 for a correlation between ozone and VOCs. correlation between ozone and VOCs.

1919

2005 Ozone vs. VOCs

0.000

0.010

0.020

0.030

0.040

0.050

0.060

0.070

April May June July August Sept Oct

Month

PP

M

880

900

920

940

960

980

1000

1020

Tons Ozone

VOC

2020

20052005Month Ozone VOC

April 0.062 1000.42

May 0.062 992.87

June 0.051 959.81

July 0.041 980.49

August 0.051 980.67

Sept 0.056 922.22

Oct 0.039 978.73

RR22 = 0.083502

2121

NOx vs. OzoneNOx vs. Ozone

Like VOCs, NOx emissions are not monitored Like VOCs, NOx emissions are not monitored like ozone.like ozone.

Division of Air Quality releases estimates of Division of Air Quality releases estimates of how much the Asheville Plant emits monthly how much the Asheville Plant emits monthly every three years.every three years.

Last time was 2005 (before any scrubbers Last time was 2005 (before any scrubbers were installed)were installed)

2222

NOx vs. OzoneNOx vs. Ozone

HypothesisHypothesis: An increase of NOX yields an : An increase of NOX yields an increase of ozone. increase of ozone.

Therefore, RTherefore, R22 > 0 for a correlation between > 0 for a correlation between ozone and NOx. ozone and NOx.

2323

2005 Ozone vs. NOx

0.000

0.010

0.020

0.030

0.040

0.050

0.060

0.070

April May June July August Sept Oct

Month

PP

M

1050

1100

1150

1200

1250

1300

1350

NO

x (t

ons)

Ozone

NOx

2424

2005 NOx vs. Ozone2005 NOx vs. OzoneMonth Ozone Nox

April 0.062 1270.39

May 0.062 1208.71

June 0.051 1161.91

July 0.041 1266.23

August 0.051 1304.84

Sept 0.056 1204.67

Oct 0.039 1311.73

RR22 = -0.43349

Negative correlation??????????

2525

ExplanationExplanation

Sunlight reacts with NOxSunlight reacts with NOx

NOx + sunlight NOx + sunlight NO + O NO + O

O + OO + O22 O O33

2626

ExplanationExplanation

The ozone created from this reaction then reacts The ozone created from this reaction then reacts with more NOx…with more NOx…

NOx + ONOx + O33 NOx + O NOx + O22

No net gain or loss of ozone!No net gain or loss of ozone!

2727

ExplanationExplanation

It’s the addition of VOCs into the atmosphere It’s the addition of VOCs into the atmosphere that alters the chemistry which contributes to that alters the chemistry which contributes to elevated levels of ozone.elevated levels of ozone.

NOx + VOC + sunlight NOx + VOC + sunlight O O33

2828

Ozone PredictionOzone Prediction

Predicting ozone levels is a lot more Predicting ozone levels is a lot more complicated than what we think.complicated than what we think.

2929

New HypothesisNew Hypothesis

In order to reduce ozone levels, we must In order to reduce ozone levels, we must reduce the sunlight or VOC amounts…reduce the sunlight or VOC amounts…

We cannot stop sunlight, so in order to We cannot stop sunlight, so in order to decrease ozone, we must accompany the NOx decrease ozone, we must accompany the NOx reduction with a VOC reduction.reduction with a VOC reduction.

Is it possible?Is it possible?

3030

The FutureThe Future

Analysis of 2008 data – is there still a negative Analysis of 2008 data – is there still a negative correlation between NOx and Ozone?correlation between NOx and Ozone?

Why was there a natural decreasing trend in Why was there a natural decreasing trend in ozone?ozone?

Possibility of a lag?Possibility of a lag?

3131

ReferencesReferences http://www.duke.edu/web/nicholas/bio217/akcarr/formation.htmlhttp://www.duke.edu/web/nicholas/bio217/akcarr/formation.html

http://www.ncair.orghttp://www.ncair.org

Tropospheric Air Pollution: Ozone, Airborne Toxics, Polycuclic Aromatic Tropospheric Air Pollution: Ozone, Airborne Toxics, Polycuclic Aromatic Hydrocarbons, and Particles.Hydrocarbons, and Particles. Pitts & Pitts Pitts & Pitts

Statistical Methods in the Atmospheric SciencesStatistical Methods in the Atmospheric Sciences. Daniel S. Wilkes. Daniel S. Wilkes

North American Mesoscale Model – Community Multiscale Air Quality Model North American Mesoscale Model – Community Multiscale Air Quality Model Ozone Forecast Verification Study For Knoxville, TN (Summer 2005).Ozone Forecast Verification Study For Knoxville, TN (Summer 2005). Loren C. Loren C. MarzMarz