Chemistry of Particles and Selected Trace Gases at Whistler, BCA.M. Macdonald, K.G. Anlauf and W.R. Leaitch

Chemistry of Particles and Selected Trace Gases at Whistler, BC

Objectives

• Establish a baseline of particle and trace gas measurements at a lower free-tropospheric site.

• Examine incidences of trans-Pacific pollution transport from Asia into western Canada.

2004/2005 Objectives/Deliverables

• Measure sulphate and other inorganic particle chemistry in the free troposphere for a three-year period (Completion of 2003 data set - May 04)

• Document frequency and duration of incidences of trans-Pacific transported pollution to the West Coast of Canada (Selection of case studies from summer 2003 - Oct 04)

• Provide background ozone climatology at a free-tropospheric site for a three-year period, including springtime maxima associated with photochemistry or troposphere-stratosphere folding events. (Completion of 2003 data set for O3 and CO May 04)

• Evaluation of site as a long-term sampling location (Mar 05)

The site is located at Whistler Peak (elevation 2182 m) and operates year-round.

Lift operator’s hut – Sep 2004 Environment Canada samplers

Instrumentation at Whistler Site March 2002 to October 2004

Ozone

CO

Filter Packs

Particle Distributions

PCASP1, DMA2

Dust Monitor

Site Visits

POPs (PBDEs, PCBs)

Mar

200

2

Ap

ril 2

002

May

200

2

Jun

e 20

02

July

200

2

Au

g 2

002

Sep

200

2

Oct

200

2

No

v 20

02

Dec

200

2

Jan

200

3

Feb

200

3

Mar

200

3

Ap

ril 2

003

May

200

3

Jun

e 20

03

July

200

3

Au

g 2

003

Sep

200

3

Oct

200

3

No

v 20

03

Dec

200

3

Jan

200

4

Feb

200

4

Mar

200

4

Ap

ril 2

004

May

200

4

Jun

e 20

04

July

200

4

Au

g 2

004

Sep

200

4

1 2

Ozone and CO calibrations

Measurement Periods

T, RH, P

2 2

• Updated logger to 23X• Updated communications software• Files regularly posted to internal web site

Results: Gas phase measurementsData set: Ozone and CO, March 2002 to presentStatus: QA/QC complete up to March 2004

Monthly averaged CO at Whistler, BC

0

50

100

150

200

250

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Month of the Year

CO

(p

pb

v)

2002

2003

2004

2003 summer average CO 20% higher than 2002 average

~ 10% increase in summer O3, 2002 to 2003

Monthly average ozone at Whistler

0

10

20

30

40

50

60

70

80

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Month

Ozo

ne (

ppbv

)

2002

2003

2004

From: Jaffe et al., GRL 2004

2003: 22.5 Mha

2002: 11.7 Mha

2004: 5.6 Mha

• Chemistry from Filter packsStatus: Flow corrected- Feb 2004

Samples analyzed –June 7, 2004

Results: Particle measurements

• Physical characterization from

(1) Grimm OPC (300 nm – 30 um) (> 80% data coverage in 2003/2004)

(2) DMA (10 nm to 400 nm)

– Dec 2003 to May 2004 (> 40% data coverage in 2003/2004)

0.00

0.25

0.50

0.75

1.00

1.25

1.50

Mar

05

, 2

002

May

04

, 2

002

Jul 0

3,

20

02

Se

p 0

1,

20

02

Oct

31

, 20

02

De

c 3

0, 2

00

2

Fe

b 2

8, 2

00

3

Ap

r 2

9, 2

00

3

Jun

28

, 2

00

3

Au

g 2

7,

20

03

Oct

26

, 20

03

De

c 2

5, 2

00

3

Fe

b 2

3, 2

00

4

Ap

r 2

3, 2

00

4

Pa

rtic

le S

ulp

ha

te <

2.5

um

, (u

g/m

3)

Particle sulphate

Particle sulphate at Whistler Peak, < 2.5 um (24 or 48 hour filter packs)

April 2002 to February 2004

Cl- NO3- Na+ K+ Mg2+ Ca2+ SO4= NH4+

Cl- , N

O3- , N

a+, K

+, M

g2+

, Ca2+

(g

m-3

)

-0.02

0.00

0.02

0.04

0.06

0.08

0.10

SO

42

- , NH

4+ ( g

m-3

)

-0.2

0.0

0.2

0.4

0.6

0.8

1.0

1.2

Median sulphate is 0.09 g m-3 with 95 % of the samples less than 0.56 g m-3. The major cation is NH4+ with 95% of the samples less than 0.25 g m-3. Very little mass is found in Ca2+ and Mg2+ with this 2.5 m cut off.

Soluble inorganics on teflon filters – April 2002 to June 2003

Average Particle Number Distribution - Whistler PeakFeb 11 - Mar 4 and Mar 25 - Apr 28, 2003

Diameter (nm)

0 20 40 60 80 100 120 140 160 180 200 220

dN

/dL

og

D

0

1000

2000

3000

4000

5000

dN

/dlo

gD

no

rmal

ize

d t

o 1

cm

-3

0.2

0.4

0.6

0.8

1.0

1.2

1.4

• The mean distribution shows two modes, one from approximately 20 to 50 nm and a second in the accumulation mode at about 150 to 200 nm.• initial examination of 2004 data shows similar distributions

Particles at Whistler Peak, Feb 10 - April 28, 2003

Date

02/10/03 02/24/03 03/10/03 03/24/03 04/07/03 04/21/03

Pa

rtic

le M

as

s (

g m

-3)

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

SO42-, NH4

+, NO3- from filter packs

DMA

• particle mass calculated as a sum of analyzed soluble organic ions and mass estimated from the DMA for Feb – Apr 2003. Strong covariance is seen but total mass is underestimated by the soluble inorganic ions.

Mass of SO42-, NO3-, and NH4

+ from teflon filters (g m-3)

0.0 0.2 0.4 0.6 0.8 1.0 1.2Mas

s ca

lcu

late

d f

rom

Par

ticl

e D

istr

ibu

tio

ns

(g

m-3

)

0.0

0.2

0.4

0.6

0.8

1.0

1.2

DMA averaged over Filter PeriodDMA + Corresponding Grimm

• soluble inorganics account for 5-20% of total mass in these samples Feb to April 2003

• VanCuren (2003) found major fine particle fractions at Crater Lake and Mount Lassen to be ~ 30% mineral, 28% organic, 4% EC, 10% sulphate, <5% nitrate, <1% sea salt

Total number of particles > 0.3 micronsSep 2003 to Sep 2004

0

20

40

60

80

100

120

Se

p 1

6,

20

03

Oct

16

, 20

03

No

v 1

5, 2

00

3

De

c 1

5, 2

00

3

Jan

14

, 2

00

4

Fe

b 1

3, 2

00

4

Mar

14

, 2

004

Ap

r 1

3, 2

00

4

May

13

, 2

004

Jun

12

, 2

00

4

Jul 1

2,

20

04

Au

g 1

1,

20

04

Se

p 1

0,

20

04

N (

cm-3

)

• Need to separate influence from local/regional biomass burning

MODIS Image

Source: Earth Observatory

Lonesome Lake Fire, July 28, 2004

Other tools available:

Trajectories, TOMS Aerosol Index

Deliverables 2003/2004:

2004/2005 Objectives/Deliverables

• Measure sulphate and other inorganic particle chemistry in the free troposphere for a three-year period (Completion of 2003 data set - May 04)

• Document frequency and duration of incidences of trans-Pacific transported pollution to the West Coast of Canada (Selection of case studies from summer 2003 - Oct 04) March 05

• Provide background ozone climatology at a free-tropospheric site for a three-year period, including springtime maxima associated with photochemistry or troposphere-stratosphere folding events. (Completion of 2003 data set for O3 and CO May 04)

• Evaluation of site as a long-term sampling location (Mar 05)

Next Steps:• Installation of temperature sensors at various altitudes.• Continue sampling, increase particle physical measurements• Continue data QA/QC• Installation of NOx instrument• Look for transport scenarios• Collaboration for modeling, vertical profile data• AMS on site for spring 2005 period•

Acknowledgements

Data analysis - Art Tham

Web site – Gary Chung, Kathy Hayden

Site visits – Dave Halpin, Maurice Watt, Kathy Hayden,

John Deary

Sample analyses – CAPMoN

Site operators - Juniper Buller, Anton Horvath