Measurements of PANs, OVOC, and Nitriles During INTEX-A

H. Singh, D. Herlth, L. Salas, R. Kolyer, E. Czech

1 10 100 10000

2

4

6

8

10

12

Mixing ratio, ppt

Alti

tude

, km

PPN

TAN MEK

C2H

5OH

C2H

5CHO

CH3OH(CH

3)2CO

PAN

CH3CHO

CH3OOH

CH2O

0 1000 2000 3000 4000

�Ox-organics

Mixing ratio, ppt

�NMHC

•Globally abundant•Photochemically active•Large poorly known sources •Measurement uncertainties

PANAK & Chemicals

•3 Channel capillary GC/ECD-PID-RGD - Chs 1 & 2/ECD: PANs- Ch 3/PID-RGD: OVOC/Nitriles/HCs

• 200 ml cryo sampling/2-min; heated probe• Sensitivity (ppt): PANs-1; OVOC- 5 to 20; HCN- 30• PAN every 2.5 min; OVOC every 5 min

•(CH3)2CO •CH3COC2H5

•CH3OH •C2H5OH •CH3CHO •PAN•PPN•RONO2

•C2Cl4

•HCN•CH3CN• C6H6

• Data collected on all missions - No RGD channel data on Mission 11- Acetaldehyde data are only for Trop (O3<100 ppb)- Date above 35 K ft are less precise

DC-8 PANAK Data Status

CH3CN & HCN

0

2

4

6

8

10

12

0 200 400 600

HCN (median)HCN (mean)

ALT

ITU

DE,

km

HCN, PPT

0

2

4

6

8

10

12

0 60 120 180 240 300

CH3CN (median)CH3CN (mean)

ALT

ITU

DE,

km

CH3CN, PPT

0

1000

2000

3000

0

500

1000

1500

5.5 104 6 10 4 6.5 104 7 104 7.5 104 8 10 4 8.5 104

HC

N, p

pt CH3CN

ppt

UTC

0

200

400

600

0

2

4

6

8

10

12

CO

, ppb

ALT, km

HCN column = 5x1015 molec cm-2

HCN Soil Sink?

0

2

4

6

8

10

12

0 200 400 600 800 1000

Alt,

km

HCN, ppt

Mission 5 (7/8)

Soil sink?

0

2

4

6

8

10

12

0 200 400 600 800 1000

HCN, ppt

Soil sink?

Mission 6 (7/12)

Acetone & MEK

0

2

4

6

8

10

12

0 50 100 150 200 250

MEK (median)MEK (mean)

ALT

ITU

DE,

km

MEK, PPT

0

2

4

6

8

10

12

0 1000 2000 3000 4000

Acetone (median)Acetone (mean)

ALT

ITU

DE,

km

Acetone, PPT

Methanol & Ethanol

0

2

4

6

8

10

12

0 100 200 300 400 500

Ethanol (median)Ethanol (mean)

ALT

ITU

DE,

km

Ethanol, PPT

0

2

4

6

8

10

12

0 1000 2000 3000 4000 5000

Methanol (median)Methanol (mean)

ALT

ITU

DE,

km

Methanol, PPT

Biogenic Sources?

0

2000

4000

6000

8000

1 104

0 100 200 300 400 500 600

Met

hano

l, pp

t

MEK, ppt

0

2000

4000

6000

8000

1 104

0 100 200 300 400 500 600

Ace

tone

, ppt

MEK, ppt

Upper Tropospheric Influences

0

100

200

300

400

500

0 200 400 600 800 1000

Ozo

ne, p

pt

PAN, ppt

UT 8-12 km

0

100

200

300

400

500

0 200 400 600 800 1000

MEK

, ppt

PAN, ppt

UT 8-12 km

0

2000

4000

6000

8000

1 104

0 200 400 600 800 1000

Ace

tone

, ppt

PAN, ppt

UT 8-12 km

0

2000

4000

6000

8000

1 104

0 200 400 600 800 1000

Met

hano

l, pp

t

PAN, ppt

UT 8-12 km

PAN & ΣPAN

0

500

1000

1500

0

2

4

6

8

10

12

4.5 104 5 104 5.5 104 6 104 6.5 104 7 104 7.5 104 8 104 8.5 104

PAN

/ΣPA

N, p

pt

UTC

M19

0

2

4

6

8

10

12

0 100 200 300 400 500

PAN (median)PAN (mean)

ALT

ITU

DE,

Km

PAN, PPT

Benzene/PID

0

50

100

150

200

250

300

0

2

4

6

8

10

12

4.5 104 5 104 5.5 104 6 104 6.5 104 7 104 7.5 104 8 104 8.5 104

benz

ene,

ppt ALTP

UTC

M19

0

2

4

6

8

10

12

0 30 60 90 120 150

Benzene (median)Benzene (mean)

ALT

ITU

DE,

km

Benzene, PPT

Acetaldehyde

0

2

4

6

8

10

12

0 100 200 300 400 500

Acetaldehyde (median)Acetaldehyde (mean)

ALT

ITU

DE,

km

Acetaldehyde, ppt

DC-8

P-3

Ongoing Focus

• Biogenic/anthropogenic emission sources of OVOC • Sources/sinks of HCN/CH3CN• Input from models• Further data and trajectory analysis• Reconciliation of measurements?• Manuscripts

– Overview paper– Sources/sinks of OVOC/PAN/HCN– Role of OVOC in HOx/NOx chemistry