1 AIR QUALITY TRENDS IN THE CITY OF COLOMBO R.N.R.Jayaratne Senior Environmental Officer Central...

11

AIR QUALITY TRENDS IN AIR QUALITY TRENDS IN THE CITY OF COLOMBOTHE CITY OF COLOMBO

R.N.R.Jayaratne R.N.R.Jayaratne Senior Environmental OfficerSenior Environmental OfficerCentral Environmental AuthorityCentral Environmental Authority

Prof. O.A.IleperumaProf. O.A.IleperumaSenior LecturerSenior LecturerUniversity of PeradeniyaUniversity of Peradeniya

National Stakeholders Forum – Sri Lanka – 12th June 2007

2

Two continuous Ambient Air Quality Monitoring Stations were set up in December 1996 at Colombo Municipal Council area under World Bank Funded project called CUTP.

- to monitor major air pollutants (NO,NO2,NOX, SO2, O3,CO & PM10) - with meteorological parameters (WS,WD,VWS, SR,RF,ATE)

One of these monitoring station is located at Colombo Fort Railway station premises and other one was located at Meteorological Department premises.

Met Department one was operated from 1997 to 2000. Colombo Fort one has been in operation since 1997


3

Location of the Colombo Fort Monitoring Station

Ambient Air Quality Monitoring station (Colombo Fort)

Kelanitissa Power Station (Thermal)

Barge Mountained Power Plant (Thermal)

N


4

Ambient Air Quality Monitoring Station 2 (Meteorological Dpt)

Ambient Air Quality Monitoring Station 1 (Colombo Fort Railway Stn)

Kelanithissa Power Plant

Barge Mountained Power Plant

Locations of Two Ambient Air Quality Monitoring Stations

5

Colombo Fort Ambient Air Quality Monitoring Station Inside of the monitoring station


6

Monitoring Principles

Ozone UV Absorption

Carbon Monoxide Non Dispersive Infra Red (NDIR)

Nitrogen Oxides Chemiluminescence

Sulfur Dioxide UV Fluorescence

PM10 High Volume Sampling


7

• Five minute and one hour average concentrations of measured parameters were recorded in data logger.

• Every day at midnight an automatic calibration cycle is carried out to check the accuracy and validity of data.

• All valid data collected from these two monitoring stations from January 1997 to Dec 2006 were used for this analysis.


8

• To identify the trend and variations of major air pollutants for the city of Colombo during the monitoring period.

(This report will also help to identify gaps

in the available information and data requirements for long term monitoring.)


9

Methodology• Converted all recorded data in binary form in

the data logger into digital form by using WINCOLLECT software .

• Screened the data base to select good data (Validation) based on daily calibration and instrument errors.

• All valid data are presented by diagrams, graphs and tables to identify features and variation patterns easily.

• Interpretations are made in scientific manner with recommendations.


10

Maximum concentration

75th percentile

Arithmetic mean of data values

25th percentile

Minimum concentration

Trends on air pollutants in Colombo

Trend graphs of nitrogen dioxide, sulfur dioxide, carbon monoxide, ozone for both monitoring stations are presented in graphical form and the statistical parameters represented as in the following format.


11

0.00

0.04

0.08

0.12

Jan-

97

Jul-

97

Jan-

98

Jul-

98

Jan-

99

Jul-

99

Jan-

00

Jul-

00

Jan-

01

Jul-

01

Month

NO

2 C

on

cen

trat

ion

(p

pm

)

National standard 0.13 ppm

Trend line (Average)

Variation of Nitrogen Dioxide (NO2) One Hour Average Concentrations at

Colombo Fort Ambient Air Quality monitoring station(1997-2001)


12

0.00

0.16

0.32

Jan

-97

Jul-

97

Jan

-98

Jul-

98

Jan

-99

Jul-

99

Jan

-00

Jul-

00

Jan

-01

Jul-

01

Month

SO2

Con

cent

rati

on (

PP

M)


Variation of Sulfur Dioxide (SO2) One Hour Averages concentrations at

Colombo Fort Ambient Air Quality monitoring station

SO

2(p

pm

)


13

0.0

1.3

2.5

3.8

Jan-

97

Jul-9

7

Jan-

98

Jul-9

8

Jan-

99

Jul-9

9

Jan-

00

Jul-0

0

Jan-

01

Jul-0

1

Month

CO

Co

nce

ntr

atio

n (p

pm)

Variation of Carbon Monoxide (CO) One Hour Average Concentrations at Colombo Fort Ambient Air Quality monitoring station (1997-2001)


14

0.0

0.2

0.4Ja

n-97

Jul-9

7

Jan-

98

Jul-9

8

Jan-

99

Jul-9

9

Jan-

00

Jul-0

0

Jan-

01

Jul-0

1

Month

O3

Con

cent

ratio

nse

(ppm

)Variation of ozone (O3) One Hour Average Concentrations at Colombo Fort

Ambient Air Quality monitoring station(1997-2001)


O3

Con

cent

ratio

n (p

pm)


15

0.00

0.04

0.08

0.12

Jan

-97

Mar

-97

May

-97

Ju

l-9

7

Sep

-97

Nov-

97

Jan

-98

Mar

-98

May

-98

Ju

l-9

8

Sep

-98

Nov-

98

Jan

-99

Mar

-99

May

-99

Ju

l-9

9

Sep

-99

Nov-

99

Jan

-00

Mar

-00

May

-00

Ju

l-0

0

Sep

-00

Nov-

00

Month

Co

nce

ntr

ati

on

(p

pm

)

National Standard 0.13 ppm

Variation of monthly one hour averages of Nitrogen Dioxide (NO2)concentrations at Colombo Meteorological Department Air Quality monitoring station

(From Jan 1997 to December 2000)


16

0.00

0.02

0.04

0.06

0.08

0.10J

an

-97

Ma

y-9

7

Se

p-9

7

Ja

n-9

8

Ma

y-9

8

Se

p-9

8

Ja

n-9

9

Ma

y-9

9

Se

p-9

9

Ja

n-0

0

Ma

y-0

0

Se

p-0

0

Month

Co

nc

en

tra

tio

n (

pp

m)

Variation of monthly one hour averages of Sulfur Dioxide (SO2) concentrations at Colombo Meteorological Department Air Quality monitoring station



17

0

1

2

3

4

5

Ja

n-9

7

Ma

y-9

7

Se

p-9

7

Ja

n-9

8

Ma

y-9

8

Se

p-9

8

Ja

n-9

9

Ma

y-9

9

Se

p-9

9

Ja

n-0

0

Ma

y-0

0

Se

p-0

0

Month

Co

nc

en

tra

tio

n (

pp

m)

Variation of monthly one hour averages of Carbon monoxide (CO) concentrations at Colombo Meteorological Department Air Quality monitoring station



18

0.00

0.04

0.08

0.12

Month

Variation of monthly one hour averages of ozone (O3) concentrations at Colombo Meteorological Department Air Quality monitoring station



19

Nitrogen Dioxide Concentration Monthly Mean and Maximum of one hour averages at Colombo Fort

( June 2003 - December 2006)

y = 0.0001x + 0.0143

0.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

Jun

Jul

Au

g

Sep Oct

No

vD

ec

Jan

Feb

Mar

Ap

r

May

Jun

Jul

Au

g

Sep Oct

No

vD

ec

Jan

Feb

Mar

Ap

r

May

Jun

Jul

Au

g

Sep Oct

No

v

Dec

Jan

Feb

Mar

Ap

r

May

Jun

July

Au

gu

st

Sep

tem

ber

Oct

ob

er

No

vem

ber

Dec

emb

er

2003 2004 2005 2006

Month and Year

Co

nce

ntr

atio

ns

(pp

m)

NO2 Mean

NO2 Maximum

Linear (NO2 Mean)

National Ambient Air Quality Strandard for NO 2 for one hour average = 0.013 ppm


20

Sulphur Dioxide Concentration Monthly Mean and Maximum of 1 hour averages at Colombo Fort

( June 2003 - December 2006 )

y = 2E-05x + 0.0068

0.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

0.16

Jun

Jul

Au

g

Sep Oct

No

v

Dec

Jan

Feb

Mar

Ap

r

May

Jun

Jul

Au

g

Sep Oct

No

v

Dec

Jan

Feb

Mar

Ap

r

May

Jun

Jul

Au

g

Sep Oct

No

v

Dec

Jan

Feb

Mar

Ap

r

May

Jun

July

Au

gu

st

Sep

tem

ber

Oct

ob

er

No

vem

ber

Dec

emb

er

2003 2004 2005 2006

Month and Year

Co

nc

en

tra

tio

n (

pp

m)

SO2 Mean

SO2 Maximum

Linear (SO2 Mean)

National Ambient Air Quality Strandard for SO2 for one hour average =0 .08 ppm

21

Carbon Monoxide Concentration Monthly Mean and Maximum of 1 hour averages at Colombo Fort

( June 2003 - December 2006 )

y = -0.0217x + 1.0988

0

1

2

3

4

5

6

7

8

9

Jun

Jul

Au

g

Sep Oct

No

v

Dec

Jan

Feb

Mar

Ap

r

May

Jun

Jul

Au

g

Sep Oct

No

v

Dec

Jan

Feb

Mar

Ap

r

May

Jun

Jul

Au

g

Sep Oct

No

v

Dec

Jan

Feb

Mar

Ap

r

May

Jun

July

Au

gu

st

Sep

tem

ber

Oct

ob

er

No

vem

ber

Dec

emb

er

2003 2004 2005 2006

Month and Year National Ambient Air Quality Strandard for 24 hour average = 26 ppm

Co

nc

en

tra

tio

n (

pp

m)

CO Average

CO Maximum

Linear (CO Average)

22

Variation of 24 hour averages of PM10 concentrations at Colombo Fort Air Quality monitoring station (From Jan 1997 to December 2001)

23

0

20

40

60

80

100

120

140

16013

-May

-00

20-M

ay-0

0

27-M

ay-0

0

3-Ju

n-00

10-J

un-0

0

17-J

un-0

0

24-J

un-0

0

1-Ju

l-00

8-Ju

l-00

15-J

ul-0

0

22-J

ul-0

0

29-J

ul-0

0

5-A

ug-0

0

12-A

ug-0

0

19-A

ug-0

0

26-A

ug-0

0

2-S

ep-0

0

9-S

ep-0

0

16-S

ep-0

0

23-S

ep-0

0

30-S

ep-0

0

7-O

ct-0

0

14-O

ct-0

0

21-O

ct-0

0

28-O

ct-0

0

Date

Con

cen

trat

ion

( μ

gm-3

)

USEPA Standard Value 150µgm-3

Variation of 24 hour averages of PM10 concentrations at Colombo Meteorological Department Air Quality monitoring station


24

0

40

80

120

160

Ja

n-0

2

Ap

r-0

2

Ju

l-0

2

Oc

t-0

2

Ja

n-0

3

Ap

r-0

3

Ju

l-0

3

Oc

t-0

3

Ja

n-0

4

Ap

r-0

4

Date

Co

ncen

trati

on

(µ

g/m

-3) Standard Value 150 µg/m-3

Trend line

Variation of monthly one hour averages of PM10 concentrations at Colombo Fort Air Quality monitoring station (From Jan 2002 to June 2004)

25

Variation of PM-10 concentrations (24 hour average) at Colombo Fort monitoring site (from 1998 to 2005)

y = -0.0109x + 79.292

0

40

80

120

160

2-Ju

l-98

15-S

ep-9

8

22-N

ov-

98

1-M

ar-9

9

9-Ju

n-9

9

31-A

ug

-99

19-N

ov-

99

30-J

an-0

0

15-A

pr-

00

20-J

un

-00

28-A

ug

-00

4-N

ov-

00

12-F

eb-0

1

4-D

ec-0

1

12-F

eb-0

2

4-Ju

l-02

5-Ja

n-0

3

1-Ju

l-03

7-S

ep-0

3

7-N

ov-

03

2-Ja

n-0

4

25-F

eb-0

4

13-A

pr-

04

1-Ju

n-0

4

23-J

ul-

04

12-S

ep-0

4

5-N

ov-

04

22-J

an-0

4

13-M

ar-0

4

30-A

pr-

04

20-J

un

-04

10-A

ug

-04

27-S

ep-0

4

28-N

ov-

04

2-F

eb-0

5

25-M

ar-0

5

12-M

ay-0

5

29-J

un

-05

16-A

ug

-05

3-O

ct-0

5

1998 1999 2000 2002 2003 2004 2005

Date and year

Co

nce

ntr

atio

n µ

gm

-3

Series1 Linear (Series1)24 hour average Trend line

26

Annual averages of PM-10 at Colombo Fort Monitoring site (1998-2006)

0

25

50

75

10019

98

1999

2000

2001

2002

2003

2004

2005

2006

Year

µg

/m3

PM

10 A

nn

ual

Ave

rag

e co

nce

ntr

atio

n

g/m

-3

Standard - 50 μgm-3

27

Increasing amount of air pollutants with increasing number of

vehicles and the capacity of thermal power generation utilizing

fossil fuels were the major reasons for these increasing trends.

Increasing number of brand new passenger transport vehicles instead of re-conditioned vehicles the major reasons for these slight increasing trends

Increasing trends of NO2,SO2 & PM10

Improvements of internal combustion engines to reduce emission, gradually decreasing of petrol driven vehicles in the vicinity of monitoring station are the major reasons and another possible reason was reaching more ultraviolet radiation into the lower atmosphere stimulating of producing hydroxyl free radicals for decline of carbon monoxide

Decreasing trend of CO

28

0.140.120.100.080.060.040.020.00

4000

3000

2000

1000

0

NO2

Fre

quency

0.140.120.100.080.060.040.020.00

2000

1000

0

NO2

Fre

quency

0.140.120.100.080.060.040.020.00

10000

5000

0

SO2

Fre

quency

0.140.120.100.080.060.040.020.00

5000

4000

3000

2000

1000

0

SO2

Fre

qu

en

cy

Comparisons of the variations of air quality monitoring data between Colombo Fort and Meteorological department sites

NO2 Concentration (One hour average) in ppm

Frequency distribution of NO2 one hour average concentrations at Colombo Fort (1997-2004)

NO2 Concentration (One hour average) in ppm

Frequency distribution of NO2 one hour average concentrations at Meteorological department (1997-2000)

SO2 Concentration (One hour average) in ppm

Frequency distribution of SO2 one hour average concentrations at Colombo Fort (1997-2004)

SO2 Concentration (One hour average) in ppm

Frequency distribution of SO2 one hour average concentrations at Meteorological department (1997-2000)

Nat

ion

al s

tan

dar

d 0

.13

pp

mN

atio

nal

sta

nd

ard

0.1

3 p

pm

Nat

ion

al s

tan

dar

d 0

.08

pp

mN

atio

nal

sta

nd

ard

0.0

8 p

pm

29

6.04.83.62.41.20.0

7000

6000

5000

4000

3000

2000

1000

0

CO

Fre

quency

6.04.83.62.41.20.0

3000

2000

1000

0

CO

Fre

quen

cy

0.40.30.20.10.0

7000

6000

5000

4000

3000

2000

1000

0

O3

Fre

qu

en

cy

0.40.30.20.10.0

5000

4000

3000

2000

1000

0

O3

Fre

qu

en

cy

Comparisons of the variations of air quality monitoring data between Colombo Fort and Meteorological department sites Cont……

CO Concentration (One hour average) in ppm

Frequency distribution of CO one hour average concentrations at Colombo Fort (1997-2004)

O3 Concentration (One hour average) in ppm

Frequency distribution of O3 one hour average concentrations at Colombo Fort (1997-2004)

CO Concentration (One hour average) in ppm

Frequency distribution of CO one hour average concentrations at Meteorological department (1997-2000)

O3 Concentration (One hour average) in ppm

Frequency distribution of O3 one hour average concentrations at Meteorological department (1997-2000)



30

1601106010

60

50

40

30

20

10

0

Concentration (ug/m3)

Fre

quen

cy

1601106010

20

10

0

Concentration (mg/m3)

Fre

qu

en

cy

PM10 Concentration (One hour average) in ppm

Frequency distribution of PM10 24 hour average concentrations at Colombo Fort (1997-2004)

PM10 Concentration (One hour average) in ppm

Frequency distribution of PM10 24 hour average concentrations at Meteorological department (1997-2000)

Comparisons of the variations of air quality monitoring data between Colombo Fort and Meteorological department sites Cont……

USEPA standard 150 μgm-3

31

Variation of O3 concentrations with wind direction At Meteorological Department site

Galle Road

High Level Road

Meteorological Department monitoring station

2000-2900

The area between 2000-2900 from Meteorological Department site.

(High ozone concentration recorded when wind

came from this area).

32

0

500

1000

1500

2000

2500

Petr

ol

Die

se

l

Petr

ol

Die

se

l

Petr

ol

Die

se

l

Petr

ol

Die

se

l

Petr

ol

Die

se

l

Petr

ol

Die

se

l

Petr

ol

Die

se

l

Petr

ol

Die

se

l

Petr

ol

Die

se

l

Petr

ol

Die

se

l

Petr

ol

Die

se

l

Petr

ol

Die

se

l

Petr

ol

Die

se

l

1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003

Year and fuel type

Em

mis

ion

of

NO

2 (X

10

00

)gk

m-1

Motor cars Motor trycicles Motor Cycles Buses Duel purpous Lorries Others

NO2 emission of diesel three-wheelers are not included becauseDifficulty to find NO2 emission factor of diesel three-wheelersThe number of diesel three-wheelers are very few compared to other vehicle groups

60% of total number of vehicles registered in Sri Lanka are assumed to be in Colombo Metropolitan Area based on the study done by transport studies and planning center under CUTP in 1996

NO2 emission from vehicles in Colombo Metropolitan Area (g/km)

33

SO2 emission of diesel three-wheelers are not included becauseDifficulty to find SO2 emission factor of diesel three-wheelersThe number of diesel three-wheelers are very few compared to other vehicle groups

60% of total number of vehicles registered in Sri Lanka are assumed to be in Colombo Metropolitan Area based on the study done by transport studies and planning center under CUTP in 1996

0

200

400

600

800

Petr

ol

Die

se

l

Petr

ol

Die

se

l

Petr

ol

Die

se

l

Petr

ol

Die

se

l

Petr

ol

Die

se

l

Petr

ol

Die

se

l

Petr

ol

Die

se

l

Petr

ol

Die

se

l

Petr

ol

Die

se

l

Petr

ol

Die

se

l

Petr

ol

Die

se

l

Petr

ol

Die

se

l

Petr

ol

Die

se

l

1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003

Year and Fuel type

Em

mis

ion

of

SO 2 (X

100

0)

gk

m-1

Motor cars Motor trycicles Motor Cycles Buses Duel purpous Lorries Others

SO2 emission from vehicles in Colombo Metropolitan Area (g/km)

34

0

150

300

450

600

1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003

Year

Fu

el U

sag

e fo

r E

lect

rici

ty(X

1000

)MT

0

2

4

6

8

10

12

14

16

Em

issi

on

of

SO

2 &

NO

2 (X

106 )g

SO2 NO2 Auto Diesel Furnace Oil Naphtha

Fuel consumption and amounts of NO2 and SO2 emissions relevant to the power sector in Sri-Lanka

35

0

2000

4000

6000

8000

1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003

Year

Ele

ctr

icit

y G

en

era

tio

n (

GW

h)

Hydro Thermal Self Genaration Wind Total Generation

Electricity generation of Sri-Lanka

36

First intermonsoon (March-April)

15%

Northeast monsoon (December- February)

13%

Second intermonsoon

(October - November)

28%Southwest monsoon

(May - September) 44%

Rainfall data- Report on Climate by M.B.G.de Silva based on rainfall data from 1961-1990

in Arjun’s Atlas of Sri Lanka

Variation of rainfall in four seasons during the year in Colombo

37

Central Environmental Authority

Station: Fort

12/1/1998 to 2/27/1999

90

68

45

22

0

338

315

292

270

248

225

202

180

158

135

112

0 to 1

1 to 2

2 to 4

4 to 6

6 to 8

> 8

Magnitude()

0.0% calm

N

94.4% Valid Data present.


Station: Fort

3/1/1999 to 3/30/1999

90

68

45

22

0

338

315

292

270

248

225

202

180

158

135

112

0%

10%

20%

30%

0 to 1

1 to 2

2 to 4

4 to 6

6 to 8

> 8

Magnitude()

0.0% calm

N


Dfgggfsgga

Rainfall 13%

Rainfall 15%

Wind pattern of four monsoonal seasons during the year at Colombo Fort monitoring station

Magnitude(ms-1)

Magnitude(ms-1)

North-East monsoon (December – February)

First inter-monsoon (March – April)

38


Station: Fort

5/1/1999 to 9/29/1999

90

68

45

22

0

338

315

292

270

248

225

202

180

158

135

112

0%

10%

20%

30%

40%

0 to 1

1 to 2

2 to 4

4 to 6

6 to 8

> 8

Magnitude()

0.0% calm

N



Station: Fort

10/1/1999 to 11/29/1999

90

68

45

22

0

338

315

292

270

248

225

202

180

158

135

112

0%

10%

20%

30%

0 to 1

1 to 2

2 to 4

4 to 6

6 to 8

> 8

Magnitude()

0.0% calm

N


Go

Rainfall 44%

Rainfall 28%

Wind pattern of four monsoonal seasons during the year at Colombo Fort monitoring station

South-west monsoon (May to September )

Second inter-monsoon (October to November)

Magnitude(ms-1)

Magnitude(ms-1)

39

Variation of air pollutant concentrations with time and date

The statistical parameters calculated with respect to the time and date were presented in graphical form to study the variation patterns during the day and the week.The statistical parameters of air pollutants are represented in these graphs in following format.

75th Percentile

Average

25th Percentile

40

0.00

0.01

0.01

0.02

0.02

0.03

0.03

0.04

0:0

0

2:0

0

4:0

0

6:0

0

8:0

0

10

:00

12

:00

14

:00

16

:00

18

:00

20

:00

22

:00

TIME

Co

nc

en

tra

tio

n (

pp

m)

0.00

0.01

0.01

0.02

0.02

0.03

0.03

0.04

0:0

0

2:0

0

4:0

0

6:0

0

8:0

0

10:0

0

12:0

0

14:0

0

16:0

0

18:0

0

20:0

0

22:0

0

TIME

Co

ncen

trati

on

(p

pm

)

Variation of one hour averages of NO2 concentrations with time at Colombo Fort monitoring station

Variation of one hour averages of SO2 concentrations with time at Colombo Fort monitoring station

41

0.00

0.20

0.40

0.60

0.80

1.00

1.20

0:0

0

2:0

0

4:0

0

6:0

0

8:0

0

10:0

0

12:0

0

14:0

0

16:0

0

18:0

0

20:0

0

22:0

0

TIME

Co

ncen

trati

on

(p

pm

)

Variation of one hour averages of CO concentrations with time at Colombo Fort monitoring station

0

0.002

0.004

0.006

0.008

0:0

0

2:0

0

4:0

0

6:0

0

8:0

0

10:0

0

12:0

0

14:0

0

16:0

0

18:0

0

20:0

0

22:0

0

TIME

Co

ncen

trati

on

(p

pm

)

Variation of one hour averages of O3 concentrations with time at Colombo Fort monitoring station

42

0.00

0.00

0.01

0.01

0.02

0:00

2:00

4:00

6:00

8:00

10:0

0

12:0

0

14:0

0

16:0

0

18:0

0

20:0

0

22:0

0

TIME

Con

cent

ratio

n (p

pm)

Variation of one hour averages of NO2 concentrations with time at Colombo Meteorological Department monitoring station

0.00

0.01

0.01

0.02

0:00

2:00

4:00

6:00

8:00

10:0

0

12:0

0

14:0

0

16:0

0

18:0

0

20:0

0

22:0

0

TIME

Con

cent

ratio

n (p

pm)

Variation of one hour averages of SO2 concentrations with time at Colombo Meteorological Department monitoring station

43

0.0

0.2

0.4

0.6

0.8

1.0

1.2

0:00

2:00

4:00

6:00

8:00

10:0

0

12:0

0

14:0

0

16:0

0

18:0

0

20:0

0

22:0

0

TIME

Co

nce

ntr

atio

n (

pp

m)

Variation of one hour averages of CO concentrations with time at Colombo Meteorological Department monitoring station

0.00

0.01

0.02

0.03

0.04

0.05

0:00

2:00

4:00

6:00

8:00

10:0

0

12:0

0

14:0

0

16:0

0

18:0

0

20:0

0

22:0

0

TIME

Co

nce

ntr

atio

n (

pp

m)

Variation of one hour averages of O3 concentrations with time at Colombo Meteorological

Department monitoring station

44

Variation of air pollutant concentrations with date

0.000

0.005

0.010

0.015

0.020

0.025

0.030

Sun Mon Tue Wed Thu Fri Sat

Day

Co

nce

ntr

atio

n (

pp

m)

Variation of one hour averages of NO2 concentrations with day at Colombo Fort monitoring station

0.000

0.005

0.010

0.015

0.020

0.025


Day

Co

nce

ntr

atio

n (

pp

m)

Variation of one hour averages of SO2 concentrations with day at Colombo Fort monitoring station

45

0.00

0.01

0.01

0.02


Day

Con

cent

ratio

n (p

pm)

Variation of one hour averages of NO2 concentrations with day at Colombo Meteorological Department monitoring station

0.000

0.003

0.006


Day

Co

nce

ntr

atio

n (

pp

m)

Variation of one hour averages of SO2 concentrations with day at Colombo Meteorological Department monitoring station

46

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8


Day

Co

nce

ntr

atio

n (

pp

m)

Variation of one hour averages of CO concentrations with day at Colombo Fort monitoring station

50

60

70

80

90

100


Day

Co

nce

ntr

atio

n (

gm

-3)

Variation of 24 hour averages of PM10 concentrations with day at Colombo Fort monitoring station

47

CONCLUSIONS

Air pollution trends with respect to sulfur dioxide and nitrogen dioxide are slowly increasing while carbon monoxide is slowly decreasing.

Increasing amount of air pollutants with increasing number of vehicles and the capacity of thermal power generation utilizing fossil fuels were the major reasons for these increasing trends.

Improvements of internal combustion engines to reduce emission, gradually decreasing of petrol driven vehicles in the vicinity of monitoring station are the major reasons and another possible reason was reaching more ultraviolet radiation into the lower atmosphere stimulating of producing hydroxyl free radicals for decline of carbon monoxide

The trend with respect to PM10 is slowly increasing over the period from Jan 1998 to June 2003. However , reaseantly we observed slight decreasing of PM-10

48

CONCLUSIONS Cont…….

Emissions from increasing fleet of vehicles are the major contributor of air pollution in Colombo City.

The emissions from thermal power stations operating in and near the Colombo metropolitan area using relatively high sulfur fuel are added burden for air pollution in Colombo City.

Prevailing wind pattern and rainfall pattern with monsoons are the major factors for seasonal variation pattern of air pollutants concentrations.

PM10 concentration in Colombo city with presence of sulfur dioxide is the serious cause to concern.

49

50

1 Howard S.Peavy,Donald R. Rowe and George Tchobanoglous, (International Ed), Environmental Engineering, McGraw-Hill, Singapore(1985) p.1-8 & 418-463

2 Bernard J Nebel & Richard T Wright,(7th Ed),Environmental Science The way the world works, Prentice Hall, Upper saddle River, New Jersy.(p 524-549)

3 PGIS, University of Peradeniya, Workshop on Acid Rain Monitoring & Air Quality Monitoring and Management Proceedings,(2001).p1-5

4 Arudpragasam K.D. (Editor in chief), Man And Environment, An introduction to Environmental Studies, Central Environmental Authority , Colombo 10, (1999), p129-164

5 UEPA,APTI, Air Pollution Control Orientation Course Self-Instructional Manual, Air Pollution Training Institute(APTI),Environmental Research Center , NC 27711,USA (1992)

6 Lakdasa Wijethilake and Suhashini A.R.Karunaratne, Air Quality Management Considerations for Developing countries, World Bank Technical Paper Number 278,The World Bank, Washington D.C.(1995)

7 UNEP,Urbun air pollution,GEMS Environmental library NO-04,UNEP, Niroby, Kenya (1998)

8 World Health Organization, Guidelines For Air Quality,World Health Organization, Geneva (2000)

9 Jiry Hanzak, Jaroslay Pekarec, Volatile Organic Compounds in the Atmosphere at the background level, Report on case study, Czech hydro meteorological institute, Kosetice observatory, Czech Republic

References

51

No of Exceedences- SO2 One Hour Average-Fort Railway Station Site 1997-2001

0

10

20

30

40

50

Jan-

97

Apr

-97

Jul-9

7

Oct

-97

Jan-

98

Apr

-98

Jul-9

8

Oct

-98

Jan-

99

Apr

-99

Jul-9

9

Oct

-99

Jan-

00

Apr

-00

Jul-0

0

Oct

-00

Jan-

01

Apr

-01

Jul-0

1

Oct

-01

Month

No

of E

xcee

denc

es

1-hourly SO2 Exceedences vs Wind Direction

0.000

0.050

0.100

0.150

0.200

0.250

0.300

0.350

0 30 60 90 120 150 180 210 240 270 300 330 360

Wind Direction

Co

nce

ntr

atio

n (

pp

m)

Exceedences of one hour averages SO2 from national standard at

Colombo Fort Monitoring site (1997-2001)

Number of exceedences of one hour average concentration of SO2

Variation of SO2 exceedences with wind direction

52

Variation of NO2 concentrations with rain fall

Variation of SO2 concentrations with rain fall

53

Variation of CO concentrations with rain fall

Variation of O3 concentrations with rain fall

54

Variation of NO2 concentrations with wind direction

Variation of SO2 concentrations with wind direction

55

Variation of CO concentrations with wind direction

Variation of O3 concentrations with wind direction

56

Variation of NO2 concentrations with wind speed

Variation of SO2 concentrations with wind speed

57

Variation of CO concentrations with wind speed

Variation of O3 concentrations with wind speed

58

This report will provide trend information on air quality

• To assist in the development of appropriate reporting methodology

• To create systems tackling progress in air quality management

• To provide guidance and direction for policy makers, decision makers, planners and policy analysts in the private and government sectors.

59

Air pollutant

Percentage of data

captured

Percentage of missing

data

Total No of data points

Mean ppm

Median ppm

Min ppm

Max ppm

NO2 70.3% 29.7% 46161 0.019 0.017 0.00 0.121

SO2 69.9% 30.1% 45924 0.013 0.008 0.00 0.331

CO 63.7% 36.3% 41838 0.546 0.382 0.00 9.515

O3 28.1% 71.9% 15172 0.005 0.003 0.00 0.378

NO2 38.6% 61.4% 13282 0.008 0.007 0.00 0.047

SO2 43.8% 56.2% 15090 0.004 0.003 0.00 0.043

CO 40.7% 59.3% 14042 0.435 0.310 0.00 5.060

O3 39.7% 60.3% 13667 0.021 0.011 0.00 0.364

Co

lom

bo

Fo

rt

mo

nit

ori

ng

Sta

tio

nM

eteo

rolo

gic

al D

epar

tmen

t m

on

ito

rin

g s

tati

on

60

Total No of data points

Mean μgm-3

Median μgm-3

Min μgm-3

Max μgm-3

Colombo Fort monitoring station * 424 76.8 74 35 153

Colombo Meteorological Department monitoring station **

193 52.3 50 13 111

• PM 10 sampling was carried out once in four days from May 1997 to December 2001 and once in three days from May 2003 to June 2004.

** PM 10 sampling was carried out once in four days from May 1997 to December 2000.

Summary of monitoring data for PM10

Date post:	29-Jan-2016
Category:	Documents
Upload:	hilary-bishop
View:	241 times
Download:	0 times

1 AIR QUALITY TRENDS IN THE CITY OF COLOMBO R.N.R.Jayaratne Senior Environmental Officer Central...

Documents