Urban vs. Rural Atlanta An assessment of : 1)PM2.5 composition and trends 2)The Atlanta Urban Heat Island Effect.

Urban vs. Rural Atlanta An assessment of :1) PM2.5 composition and trends2) The Atlanta Urban Heat Island Effect

Outline•Part I: PM2.5 Compositional analysis and

trends▫Background▫Assessment▫Composition▫Spatial and temporal Analysis▫Monthly Analysis▫Meteorological Correlations

•Part II: Urban Heat Island Index and Effect▫Background▫Diurnal UHI in urban vs. rural environment▫Meteorological Correlations

•Part III: Conclusions

Part I: PM2.5: Why are we so concerned?•Aerosols•PM

▫Environmental Issues▫Health Risks

•PM2.5

▫Humans inhale it▫It diffuses

•Primary and secondary origin▫Formation poorly understood

PM2.5 Assessment• Part of Georgia Tech’s ASACA project• 3 sites

▫ Fire Station 8 (FSE) (urban) (Daily)▫ South Dekalb (SD) (urban) (Daily)▫ Yargo (YG) (rural) (1 in 3 days)

• 3 filter types▫ Quartz (EC/OC analysis)▫ Nylon (wsioi and ions)

Na+, NH4+,K+,Ca2+,Cl-,

NO2-, NO3

-, SO42- ,

CH3COO-, HCOO-, C2O42-

▫ Teflon (trace metals)

• PCM, IC, TOT, TEOM, aeth.• Only 2012 data analyzed

Figure 1: Map of the three different sampling sites. A: Fort Yargo State Park, B: Fire Station Eight, C: South Dekalb site

PM2.5 Composition in 2012

PM2.5 Analysis: Spatial and temporal

0 5 10 15 20 25 30 35 40 45 500

5

10

15

20

25

FSE_PM2.5 SD_PM2.5 YG_PM25.

0 5 10 15 20 25 30 35 40 45 500

2

4

6

8

10

12

FSE_OC SD_OC YG_OC

0 5 10 15 20 25 30 35 40 45 500

0.5

1

1.5

2

2.5

3

FSE_EC SD_EC YG_EC

0 5 10 15 20 25 30 35 40 45 500

0.5

1

1.5

2

2.5

3

3.5

4

4.5

FSE_SO4 SD_SO4 YG_SO4

PM2.5 Analysis: Spatial and temporal

0 5 10 15 20 25 30 35 40 45 500

0.2

0.4

0.6

0.8

1

1.2

1.4

FSE_NH4_Avg SD_NH4_Avg YG_NH4_Avg

0 5 10 15 20 25 30 35 40 45 500

0.2

0.4

0.6

0.8

1

1.2

1.4

FSE_NO3 SD_NO3

0 5 10 15 20 25 30 35 40 45 500

0.5

1

1.5

2

2.5

3

3.5

4

4.5

FSE_SO4 SD_SO4 YG_SO4

R Square 0.833  Adjusted R

Square 0.826  

Standard Error 0.189  

  Coefficients Standard Error P-value

Intercept 0.408 0.110 0.0011

X Variable 1 2.711 0.242 3.35E-11

PM2.5 Analysis: Monthly

0

0.5

1

1.5

2

2.5

2012 Monthly Sulfate Average

FSE

SD

YG

Avera

ge S

ulf

ate

(ug/m

3)

0 2 4 6 8 10 12 140123456789

2012 Monthly OC Average

SDYGFSE

MonthAvera

ge O

C (

mic

rog/m

3)

PM2.5 Analysis: Meteorological Correlations

11/3/2011 12/23/2011 2/11/2012 4/1/2012 5/21/2012 7/10/2012 8/29/2012 10/18/2012 12/7/2012 1/26/2013-5

0

5

10

15

20

25

30

35

40

Avg T (deg C)

40850 40900 40950 41000 41050 41100 41150 41200 41250 413000

10

20

30

40

50

60

70

Avg Windspeed (km/hr)

FSE_PMSpec

PM2.5: Meteorological Correlations

Avg Temp (deg C) - YG

0 5 10 15 20 25 300

5

10

15

20

25

30

35

f(x) = 0.395586594352332 x + 14.683149062468R² = 0.0716938847328034

Avg Temp (deg C) - YG

Avg Temp (deg C)

Linear (Avg Temp (deg C))

0 2 4 6 8 10 12 14 1605

10152025303540

f(x) = − 0.85522484224668 x + 12.3216898709307R² = 0.120202732795872

Avg Windspeed (km/hr) - SD

Avg Windspeed SD

Linear (Avg Windspeed SD)

Regression Statistics  

R Square 0.0717  Adjusted R

Square 0.0643  

Standard Error 4.727  

  Coefficients Standard Error P-value

Intercept 6.0758 1.148 5.19E-07

X Variable 1 0.181 0.058 0.00225

Regression Statistics

R Square 0.12  

Adjusted R Square 0.118  

Standard Error 4.785    

  Coefficients Standard Error P-value

Intercept 12.322 0.489 9.49E-82X Variable 1 -0.855 0.121 8.92E-12

Part II: Urban Heat Island Index and Effect•Urban Area Temperature > Rural Area

Temperature▫Population density, geography, building

structure and material, vegetation▫Urban cities trap radiation near the surface

Large differences in solar radiation and heat and water balances

11/3/2011 12/23/2011 2/11/2012 4/1/2012 5/21/2012 7/10/2012 8/29/2012 10/18/2012 12/7/2012 1/26/2013-5

0

5

10

15

UHII

UHI

Urban Atlanta Albedo

Diurnal UHI in Urban vs Rural Sites

January 16 February 16

May 1 November 7

UHII vs Meteorological Correlations

-10 -5 0 5 10 15 20 25-2

0

2

4

6

8

10

12

14

f(x) = − 0.140044318093979 x + 6.03220791713547R² = 0.114556785711402

Rel Windspeed

Rel Wind-speedLinear (Rel Windspeed)

-60 -50 -40 -30 -20 -10 0 10 20-2

0

2

4

6

8

10

12

14

f(x) = − 0.087238362886156 x + 3.70686116147751R² = 0.23778415182586

Rel. Humidity

Rel. HumidityLinear (Rel. Humidity)

Regression Statistics  

Adjusted R Square 0.236  

Standard Error 1.910  

Coefficients Standard Error P-value

Intercept 3.707 0.2194 1.15E-47

X Variable 1 -0.0872 0.00819 2.93E-23

Regression Statistics

Adjusted R Square 0.112  

Standard Error 2.059    

Coefficients Standard Error P-value

Intercept 6.032 0.1133 6.95E-174X Variable 1 -0.14 0.0204 2.92E-11

To sum up…•PM2.5 is of concern in both urban and rural

Atlanta▫Although composition similar,

concentrations need to be monitored▫Meteorological factors play a big role

•Atlanta is a hub for UHI▫More attention needed in diurnal changed

in meteorological patterns

•A lot can change in a small distance!

Special Thanks to

•2012 - 2013 ASACA team▫Jeremiah Redman▫Kyle Digby▫Boris Galvis

References

• Bell, et al. "Spatial and Temporal Variation in PM2.5 Chemical Composition in the United States for Health Effects Studies." Environmental Health Perspectives: n. pag. Print.

• Chow, et al. "PM2.5 chemical composition and spatiotemporal variability during the California Regional PM10/PM2.5 Air Quality Study (CRPAQS)." Journal of Geophysical Research Atmospheres: n. pag. Print.

• Clarke, Azadi-Boogar, and Andrews. "Particle size and chemical composition of urban aerosols." Science of the Total Environment: n. pag. Print.

• Kim. "Urban Heat Island." International Journal of Remote Sensing 13.12 (1992): n. pag. Print.

• Myrup. "A Numerical Model of the Urban Heat Island." American Meteorology Society: n. pag. Print.

• Myrup, Leonard. "A Numerical Model of Urban Heat Island." Journal of Applied Meteorology: n. pag. Print.

• The Urban Environment. N.p., n.d. Web. 24 Apr. 2013. <http://www.coa.gov.in/mag/Archi_Apr09-Lowres-pdf/20-25-Urban%20heat%20island.pdf>.

• Weng, Lu, and Schubring. "Estimation of land surface temperature–vegetation abundance relationship for urban heat island studies." Remote Sensing of Environment 89.4 (2004): n. pag. Print.

Any questions?Thanks for listening!