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222 Analytical Techniques for Atmospheric Measurement

134.7 nm. The calibration constants produced by these three independent methods agreed

to within their stated uncertainties. The absorption technique proved the most versatile

and convenient method for routine calibrations. An absorption technique was similarly

used to calibrate the Br detection axes at 145.8 nm.

4.5.2 Balloon-borne instruments

Early balloon-borne instruments measured Cl, ClO, and BrO in air that flowed through

the interior of an aerodynamically shaped pod (or nacelle) as it descended from altitudes

as high as 44 km (Anderson et al., 1977, 1980; Brune & Anderson, 1986), similar to

balloon-borne OH measurements. After ascending to float altitudes while attached to

a balloon, instruments were detached and descended on a stabilized parachute through

the stratosphere at speeds of 40–100 m/s. The first instruments measured Cl and ClO on

separate identical detection pods mounted on a common support frame (Anderson et al.,

1977, 1980) so that both species could be measured simultaneously. The background of

the Cl instrument was measured by titrating ambient Cl with ethane injected below the

detection point. Later versions (Brune & Anderson, 1986) measured only ClO and BrO

on the two pods.

4.5.3 Aircraft measurements

Instruments that measured ClO and BrO were installed on the wing pod of the ER-2

aircraft for missions flying into the polar vortex (Brune et al., 1989a,b). The instrument’s

inlet design was the basis for the design described for OH measurements (Section 4.3.2).

A double-duct design was used to deliver a laminar flow of unperturbed air to three

consecutive detection axes. NO was added prior to the first detection axis. ClO was

measured using the first two axes while BrO was measured with the third. Sample flow

conditions were monitored by measurement of the gas temperature using a thermistor

bead array downstream of the detection axes.

All axes were calibrated on the ground before and after flights. After calibration of the

Cl axes, the bromine axis was then calibrated to a known Br concentration produced by

the reaction

Cl +Br

→ BrCl +Br (4.32)

where the concentration of the limiting reagent Cl is measured by the calibrated Cl

detection axes. Both axes monitored Rayleigh scattering as an in-flight proxy calibration.

4.5.4 ClONO

and ClOOCl

Later developments made possible the measurement of chlorine nitrate ClONO



(Stimpfle et al., 1999) and the chlorine monoxide dimer (ClOOCl) (Stimpfle et al., 2004)

Fluorescence Methods 223

aboard the ER-2 aircraft. Both compounds are measured by thermal dissociation followed

by detection of ClO:

ClONO



−→ClO +NO

+M H = 113 kJ/mol (4.33)

ClOOCl +M



−→ClO +ClO +M H = 71kJ/mol (4.34)

The air flow is heated by a grid of resistively heated silicon strips. Due to the difference in

bond energies, ClONO

and ClOOCl dissociate fully at different temperatures. A parallel

pair of flows is utilized, each with two consecutive detection axes. One flow measures

ClO in the first detection axis and either ClONO

or ClOOCl in the second depending

on heater temperature. The other flow measures BrO in the first axis and uses the

second detection axis for diagnostics of the dissociation temperature of the mirror image

ClONO

/ClOOCl axis.

The detection limit for ClO is 3 ppt in a 35-second integration with an uncertainty of

17% 1 (Stimpfle et al., 2004). ClONO

and ClOOCl are measured with a detection

limit of 10 ppt in the same integration period, with an uncertainty of 21% 1 (Stimpfle

et al., 2004). At an air density of 26 ×10

molecules cm

−3

, the detection limit for BrO

aboard the ER-2 was 16 ppt in a 1-minute integration, and SNR =2, with an uncertainty

of 18% 1 (Brune et al., 1989a).

4.6 Future directions

The application of fluorescence to measurements of atmospheric trace gases is expanding

rapidly. New laser technologies based on diodes or frequency mixing are greatly extending

the range of excitation wavelengths that can be produced and hence molecules that

can be detected in a portable package. For example, the use of blue laser diodes by

the data storage industry, currently in its infancy, will likely fuel new developments in

detection (or after frequency-doubling, NO detection). Reductions in the size and

increases in the autonomy of fluorescence instruments will allow for more widespread

application of the technique, enabling advances in atmospheric sciences. In particular, it

will become (1) simpler to assemble the comprehensive suites of chemical measurements

that are now critical to advancing mechanistic atmospheric chemistry research, and (2)

become possible to construct large scale networks with hundreds of sensors that permit

observations of spatial and long-term trends in key indicators of the health of the

atmosphere.

Further reading

Atkins, P.W., de Paula J. (2002) Physical Chemistry, 7th edition, Oxford University Press, New York.

McClenny, W.A., Williams, E.J., Cohen, R.C. & Stutz, J. (2002) Preparing to measure the effects

of the NO

SIP call: Methods for ambient monitoring of NO, NO

,NO

and individual NO

species, J. Air Waste Manag., 52(5), 542–562.

224 Analytical Techniques for Atmospheric Measurement

Brune, W.H. & Richard M. Stimpfle (1993) In Situ Measurements of Stratospheric Reactive Trace

Gases, Chapter 5 of Measurement Challenges in Atmospheric Chemistry, Leonard Newman (ed.),

Advances in Chemistry series 232.

Anderson, J.G. (1995) Polar Processes in Ozone Depletion, Chapter 17 of Progess and Problems in

Atmospheric Chemistry, Editor John R. Barker, Advanced Series in Physical Chemistry, vol. 3,

World Scientific, 1995.

References

Anderson, J.G. (1971a) J. Geophys. Res., 76, 7820–7824.

Anderson, J.G. (1971b) J. Geophys. Res., 76, 4634–4652.

Anderson, J.G. (1975) Geophys. Res. Lett., 2, 231–234.

Anderson, J.G. (1976) Geophys. Res. Lett., 3, 165–168.

Anderson, J.G., Brune, W.H. & Proffitt, M.H. (1989) J. Geophys. Res. Atmos., 94, 11 465–11 479.

Anderson, J.G., Grassl, H.J., Shetter, R.E. & Margitan, J.J. (1980) J. Geophys. Res., 85, 2869–2887.

Anderson, J.G., Grassl, H.J., Shetter, R.E. & Margitan, J.J. (1981) Geophys. Res. Lett., 8, 289–292.

Anderson, J.G., Margitan, J.J. & Stedman, D.H. (1977) Science, 198, 501–503.

Anderson, J.G., Grassl, H.J., Shetter, R.E., Margitan, J.J. (1980) Stratospheric free chlorine measured

by balloon-borne in situ resonance fluorescence. J. Geophys. Res., 85(C5), 2869–2887.

Anderson, J.G., Toohey, D.W. & Brune, W.H. (1991) Science, 251, 39–46.

Avallone, L.M., Toohey, D.W., Brune, W.H., Salawitch, R.J., Dessler, A.E. & Anderson, J.G. (1993)

Geophys. Res. Lett., 20, 1795–1798.

Bailey, A.E., Heard, D.E., Henderson, D.A. & Paul, P.H. (1999) Chem. Phys. Lett., 302, 132–138.

Bailey, A.E., Heard, D.E., Paul, P.H., Pilling, M.J. (1997) Collisional quenching of OH A







=0

by N

 O

and CO

between 204 and 294 K. Implications for atmospheric measurements of OH by

laser-induced fluorescence. J. Chem. Soc.-Faraday Trans., 93(16), 2915–2920.

Bertram, T.H., Cohen, R.C., Thorn III, W.J. & Chu, P.M. (2005) J. Air Waste Manag. Assoc., 55(10).

Bloss, W.J., Gravestock, T.J., Heard, D.E., Ingham, T., Johnson, G.P. & Lee, J.D. (2003) J. Environ.

Monit., 5, 21–28.

Bloss, W.J., Lee, J.D., Bloss, C., Heard, D.E., Pilling, M.J., Wirtz, K., Martin-Reviejo, M. & Siese, M.

(2004) Atmos. Chem. Phys., 4, 571–583.

Bradshaw, J., Davis, D., Crawford, J., Chen, G., Shetter, R., Muller, M., Gregory, G., Sachse, G.,

Blake, D., Heikes, B., Singh, H., Mastromarino, J. & Sandholm, S. (1999) Geophys. Res. Lett.,

26, 471–474.

Bradshaw, J. & Davis, D.D. (1982) Opt. Lett., 7, 224–226.

Bradshaw, J.D., Rodgers, M.O. & Davis, D.D. (1982) Single photon laser-induced fluorescence

detection of NO and SO

for atmospheric conditions of composition and pressure. Appl. Opt.,

21(14), 2493–2500.

Bradshaw, J.D., Rodgers, M.O., Sandholm, S.T., Kesheng, S. & Davis, D.D. (1985) J. Geophys. Res.,

90, 12 861–12 873.

Brune, W.H. & Anderson, J.G. (1986) Geophys. Res. Lett., 13, 1391–1394.

Brune, W.H., Anderson, J.G. & Chan, K.R. (1989a) J. Geophys. Res.-Atmos., 94, 16 639–16 647.

Brune, W.H., Anderson, J.G. & Chan, K.R. (1989b) J. Geophys. Res.-Atmos., 94, 16 649–16 663.

Brune, W.H. & Stimpfle, R.M. (1993) Advances in Chemistry Series, 133–184.

Brus, L.E. & McDonald, J.R. (1974) Time-resolved fluorescence kinetics and B-1 1(Delta-1 G)

vibronic structure in tunable ultraviolet laser-excited SO

vapor. J. Chem. Phys., 61(1), 97–105.

Burrows, J.P., Dehn, A., Deters, B., Himmelmann, S., Richter, A., Voigt, S. & Orphal, J. (1998)

Atmospheric remote-sensing reference data from GOME: Part I. Temperature-dependent

Fluorescence Methods 225

absorption cross-sections of NO

in the 231–794 nm range, J. Quant. Spectrosc. Radiat. Transf.,

60, 1025–1031.

Calpini, B., Jeanneret, F., Bourqui, M., Clappier, A., Vajtai, R. & van den Bergh, H. (1999) Analusis,

27, 328–336.

Cantrell, C.A., Davidson, J.A., McDaniel, A.H., Shetter, R.E. & Calvert, J.G. (1990) Temperature-

dependent formaldehyde cross sections in the near-ultraviolet spectral region. J. Phys. Chem.,

94(10), 3902–3908.

Carter, R.T., Schmidt, K.F., Bitto, H. & Huber, J.R. (1996) Chem. Phys. Lett., 257, 297–302.

Cleary, P.A., Wooldridge, P.J. & Cohen, R.C. (2002) Laser-induced fluorescence detection of

atmospheric NO

with a commercial diode laser and a supersonic expansion, Appl. Opt., 41,

6950–6956.

Clough, P.N. & Thrush, B.A. (1967) Trans. Faraday Soc., 63, 915–925.

Creasey, D.J., Evans, G.E., Heard, D.E. & Lee, J.D. (2003) J. Geophys. Res.-Atmos., 108.

Creasey, D.J., HalfordMaw, P.A., Heard, D.E., Pilling, M.J. & Whitaker, B.J. (1997) J. Chem.

Soc.-Faraday Trans., 93, 2907–2913.

Crosley, D.R. (1995) J. Atmos. Sci., 52, 3299–3314.

Davis, D.D., Heaps, W. & McGee, T. (1976) Geophys. Res. Lett., 3, 331–333.

Day, D.A., Dillon, M.B., Wooldridge, P.J., Thornton, J.A., Rosen, R.S., Wood, E.C. & Cohen, R.C.

(2003) J. Geophys. Res.-Atmos., 108.

Day, D.A., Wooldridge, P.J., Dillon, M.B., Thornton, J.A. & Cohen, R.C. (2002) J. Geophys. Res.-

Atmos., 107.

Di Carlo, P., Brune, W.H., Martinez, M., Harder, H., Lesher, R., Ren, X., Thornberry, T., Carroll,

M.A., Young, V., Shepson, P.B., Riemer, D., Apel, E. & Campbell, C. (2004) Science, 304,

722–725.

Docquier, N. & Candel, S. (2002) Prog. Energy Combustion Sci., 28, 107–150.

Donnelly, V.M. & Kaufman, F. (1978) J. Chem. Phys., 69, 1456–1460.

Donnelly, V.M., Keil, D.G. & Kaufman, F. (1979) J. Chem. Phys., 71, 659–673.

Douglas, A.E. (1966) J. Chem. Phys., 45, 1007–1015.

Dubey, M.K., Hanisco, T.F., Wennberg, P.O. & Anderson, J.G. (1996) Geophys. Res. Lett., 23,

3215–3218.

Faloona, I.C., Tan, D., Lesher, R.L., Hazen, N.L., Frame, C.L., Simpas, J.B., Harder, H., Martinez, M.,

Di Carlo, P., Ren, X.R. & Brune, W.H. (2004) J. Atmos. Chem., 47, 139–167.

Fong, C. & Brune, W.H. (1997) Rev. Sci. Instrum., 68, 4253–4262.

Fried, A. & Hodgeson, J. (1982) Anal. Chem., 54, 278–282.

Fried, A., Sams, R., Dorko, W., Elkins, J.W. & Cai, Z.T. (1988) Anal. Chem., 60, 394–403.

Galloway, J.N. (2001) Water Air and Soil Pollut., 130, 17–24.

George, L.A. & O’Brien, R.J. (1991) J. Atmos. Chem., 12, 195–209.

Hard, T.M., George, L.A. & O’Brien, R.J. (1995) J. Atmos. Sci., 52, 3354–3372.

Hard, T.M., George, L.A. & O’Brien, R.J. (2002) Environ. Sci. Technol., 36, 1783–1790.

Hard, T.M., O’Brien, R.J., Chan, C.Y. & Mehrabzadeh, A.A. (1984) Environ. Sci. Technol., 18,

768–777.

Heard, D.E. & Pilling, M.J. (2003) Chem. Rev., 103, 5163–5198.

Herriott, D., Kompfner, R. & Kogelnik, H. (1964) Appl. Opt., 3, 523–526.

Hofzumahaus, A., Aschmutat, U., Brandenburger, U., Brauers, T., Dorn, H.P., Hausmann, M.,

Hessling, M., Holland, F., Plass-Duelmer, C. & Ehhalt, D.H. (1998) J. Atmos. Chem., 31, 227–246.

Holland, E.A., Braswell, B.H., Lamarque, J.F., Townsend, A., Sulzman, J., Muller, J.F., Dentener, F.,

Brasseur, G., Levy II, H., Penner, J.E. & Roelofs, G.J. (1997) J. Geophys. Res., 102, 15 849–15 866.

Holland, F., Hessling, M. & Hofzumahaus, A. (1995) J. Atmos. Sci., 52, 3393–3401.

Holland, F., Hofzumahaus, A., Schafer, A., Kraus, A. & Patz, H. (2003) J. Geophys. Res., 108,

doi:10.1029/2001JD001393.

226 Analytical Techniques for Atmospheric Measurement

Holloway, J.S., Jakoubek, R.O., Parrish, D.D., Gerbig, C., Volz-Thomas, A., Schmitgen, S., Fried, A.,

Wert, B., Henry, B. & Drummond, J.R. (2000) J. Geophys. Res.-Atmos., 105, 24 251–24 261.

Holtermann, D.L., Lee, E.K.C. & Nanes, R. (1980) Single rovibronic level lifetimes of the

state of

excited in the 3043 A (“E”) band – Rotationally resolved fluorescence emission-spectrum.

Chem. Phys. Lett., 75(1), 91–93.

Ishiwata, T., Fujiwara, I., Naruge, Y., Obi, K. & Tanaka, I. (1983) Study of NO

by laser-induced

fluorescence. J. Phys. Chem., 87(8), 1349–1352.

Jeanneret, F., Kirchner, F., Clappier, A., van den Bergh, H. & Calpini, B. (2001) J. Geophys. Res.,

106, 3083–3093.

Johnson, G.P. (2004) Ph.D. Thesis, University of Leeds, Leeds.

Johnston, H.S., Davis, H.F. & Lee, Y.T. (1996) J. Phys. Chem., 100, 4713–4723.

Kanaya, Y., Sadanaga, Y., Hirokawa, J., Kajii, Y. & Akimoto, H. (2001) J. Atmos. Chem., 38, 73–110.

Kita, K., Imamura, T., Iwagami, N., Morrow, W.H. & Ogawa, T. (1996) Ann. Geophysicae-Atmos.

Hydrospheres Space Sci., 14, 227–237.

Kovacs, T.A. & Brune, W.H. (2001) Total OH loss rate measurement, J. Atmos. Chem., 39, 105–122.

Kovacs, T.A., Brune, W.H., Harder, H., Martinez, M., Simpas, J.B., Frost, G.J., Williams, E.,

Jobson, T., Stroud, C., Young, V., Fried, A. & Wert, B. (2003) J. Environ. Monit., 5, 68–74.

Lerdau, M.T., Munger, L.J. & Jacob, D.J. (2000) Science, 289, 2291, 2293.

Levy, H. (1972) Planetary Space Sci., 20, 919–935.

Liang, J.Y., Horowitz, L.W., Jacob, D.J., Wang, Y.H., Fiore, A.M., Logan, J.A., Gardner, G.M. and

Munger, J.W. (1998) J. Geophys. Res.-Atmos., 103, 13 435–13 450.

Liao, W., Hecobian, A., Mastromarino, J. & Tan, D. (2003) American Geophysical Union, Fall

Meeting.

Logan, J.A., Prather, M.J., Wofsy, S.C. & McElroy, M.B. (1981) J. Geophys. Res.-Oceans Atmos., 86,

7210–7254.

Luke, W.T. (1997) J. Geophys. Res.-Atmos., 102, 16 255–16 265.

Luque, J. & Crosley, D.R. (2000) Radiative and predissociative rates for NO A







= 0–5 and







= 0–3. J. Chem. Phys., 112(21), 9411–9416.

Martinez, R.D. & Joens, J.A. (1992) SO

Absorption cross-section measurements from 197 nm to

240 nm. Geophys. Res. Lett., 19(3), 277–279.

Martinez, M., Harder, H., Ren, X., Lesher, R.L. & Brune, W.H. (2004) Atmos. Chem. Phys.,4,

563–569.

Matsumi, Y., Murakami, S., Kono, M., Takahashi, K., Koike, M. & Kondo, Y. (2001) Anal. Chem.,

73, 5485–5493.

Matsumoto, J., Hirokawa, J., Akimoto, H. & Kajii, Y. (2001) Atmos. Environ., 35, 2803–2814.

Matsumoto, J., Imai, H., Kosugi, N. & Kajii, Y. (2005) In situ measurement of N

in the urban

atmosphere by thermal decomposition/laser-induced fluorescence technique. Atmos. Environ.,

39, 6802–6811.

Matsumoto, J. & Kajii, Y. (2003) Atmos. Environ., 37, 4847–4851.

Mazely, T.L., Friedl, R.R. & Sander, S.P. (1994) J. Chem. Phys., 100, 8040–8046.

McGee, T.J., McIlrath, T.J. (1984) Absolute OH absorption cross-sections (for Lidar measurements).

J. Quant. Spectrosc. Radiat. Transf., 32(2), 179–184.

Mickley, L.J., Murti, P.P., Jacob, D.J., Logan, J.A., Koch, D.M. & Rind, D. (1999) J. Geophys. Res.,

104, 30 153–30 172.

Miller, R.G. & Lee, E.K.C. (1978) Single vibronic level photochemistry of formaldehydes in A

state – Radiative and nonradiative processes in H

CO, HDCO, and D

CO. J. Chem. Phys.,

68(10), 4448–4464.

Molina, M.J. & Rowland, F.S. (1974) Nature, 249, 810–812.

Moore, C.B. & Weisshaar, J.C. (1983) Formaldehyde photochemistry. Ann. Rev. Phys. Chem., 34,

525–555.

Fluorescence Methods 227

Munger, J.W., Song-Miao, F., Bakwin, P.S., Goulden, M.L., Goldstein, A.H., Colman, A.S. &

Wofsy, S.C. (1998) J. Geophys. Res., 103, 8355–8368.

Nee, J.B., Juan, C.Y., Hsu, J.Y., Yang, J.C. & Chen, W.J. (2004) The electronic quenching rates of

NOA







= 0–2. J. Chem. Phys., 300(1–3), 85–92.

Nelson, H.H., Pasternack, L. & McDonald, J.R. (1983) Excited state dynamics of NO

. J. Chem.

Phys., 79(9), 4279–4284.

Neuman, J.A., Huey, L.G., Ryerson, T.B. & Fahey, D.W. (1999) Environ. Sci. Technol., 33, 1133–1136.

Patten, K.O., Burley, J.D. & Johnston, H.S. (1990) Radiative lifetimes of nitrogen-dioxide for

excitation wavelengths from 400 nm to 750 nm. J. Phys. Chem., 94(20), 7960–7969.

Perkins, K.K., Hanisco, T.F., Cohen, R.C., Koch, L.C., Stimpfle, R.M., Voss, P.B., Bonne, G.P.,

Lanzendorf, E.J., Anderson, J.G., Wennberg, P.O., Gao, R.S., Del Negro, L.A., Salawitch, R.J.,

McElroy, C.T., Hintsa, E.J., Loewenstein, M. & Bui, T.P. (2001) J. Phys. Chem. – A, 105,

1521–1534.

Pfeiffer, L.N. & Porter, J.F. (1964) Appl. Opt., 3, 317.

Pierson, J.M., McKinney, K.A., Toohey, D.W., Margitan, J., Schmidt, U., Engel, A. & Newman, P.A.

(1999) J. Atmos. Chem., 32, 61–81.

Ren, X., Edwards, G.D., Cantrell, C.A., Lesher, R.L., Metcalf, A.R., Shirley, T. & Brune, W.H.

(2003a) Intercomparison of peroxy radical measurements at a rural site using laser-induced

fluorescence and Peroxy Radical Chemical Ionization Mass Spectrometer (PerCIMS) techniques,

J. Geophys. Res., 108, 4605.

Ren, X.R., Harder, H., Martinez, M., Lesher, R.L., Oliger, A., Simpas, J.B., Brune, W.H., Schwab, J.J.,

Demerjian, K.L., He, Y., Zhou, X.L. & Gao, H.G. (2003b) Atmos. Environ., 37, 3639–3651.

Ren, X.R., Harder, H., Martinez, M., Faloona, I.C., Tan, D., Lesher, R.L., Di Carlo, P., Simpas, J.B.

& Brune, W.H. (2004) J. Atmos. Chem., 47, 169–190.

Rodgers, M.O. & Davis, D.D. (1989) Environ. Sci. Technol., 23, 1106–1112.

Russell, A. & Dennis, R. (2000) Atmos. Environ., 34, 2283–2324.

Ryerson, T.B., Huey, L.G., Knapp, K., Neuman, J.A., Parrish, D.D., Sueper, D.T. & Fehsenfeld, F.C.

(1999) J. Geophys. Res.-Atmos., 104, 5483–5492.

Ryerson, T.B., Williams, E.J. & Fehsenfeld, F.C. (2000) J. Geophys. Res.-Atmos., 105, 26 447–26 461.

Sackett, P.B. & Yardley, J.T. (1972) J. Chem. Phys., 57, 152–163.

Sadanaga, Y., Matsumoto, J., Sakurai, K., Isozaki, R., Kato, S., Nomaguchi, T., Bandow, H. &

Kajii, Y. (2004a) Rev. Sci. Instrum., 75, 864–872.

Sadanaga, Y., Yoshino, A., Watanabe, K., Yoshino, A., Wakazono, Y., Kanaya, Y. & Kajii, Y. (2004b)

Rev. Sci. Instrum., 75, 2648–2655.

Sandholm, S., Smyth, S., Bai, R. & Bradshaw, J. (1997) J. Geophys. Res., 102, 28 651–28 661.

Sandholm, S.T., Bradshaw, J.D., Dorris, K.S., Rodgers, M.O. & Davis, D.D. (1990) J. Geophys. Res.,

95, 10 155–10 161.

Schultz, M., Heitlinger, M., Mihelcic, D. & Volz-Thomas, A. (1995) J. Geophys. Res., 100,

18 811–18 816.

Shibuya, K. & Lee, E.K.C. (1978) Vibrational and electronic-energy transfers from a single vibronic

level of H

COa

,4

level. J. Chem. Phys., 69(2), 758–766.

Smith, P.S. & Crosley, D.R. (1990) J. Geophys. Res., 95, 16 427–16 422.

Steinfeld, J.I. & Wormhoudt, J. (1998) Ann. Rev. Phys. Chem., 49, 203–232.

Stevens, P.S., Mather, J.H. & Brune, W.H. (1994) J. Geophys. Res., 99, 3543–3557.

Stimpfle, R.M. & Anderson, J.G. (1988) Geophys. Res. Lett., 15, 1503–1506.

Stimpfle, R.M., Cohen, R.C., Bonne, G.P., Voss, P.B., Perkins, K.K., Koch, L.C., Anderson, J.G.,

Salawitch, R.J., Lloyd, S.A., Gao, R.S., Del Negro, L.A., Keim, E.R. & Bui, T.P. (1999) J. Geophys.

Res., 104, 26 705–26 714.

Stimpfle, R.M., Wennberg, P.O., Lapson, L.B. & Anderson, J.G. (1990) Geophys. Res. Lett., 17,

1905–1908.

228 Analytical Techniques for Atmospheric Measurement

Stimpfle, R.M., Wilmouth, D.M., Salawitch, R.J. & Anderson, J.G. (2004) J. Geophys. Res., 109,

JD003811.

Takegawa, N., Kita, K., Kondo, Y., Matsumi, Y., Parrish, D.D., Holloway, J.S., Koike, M.,

Miyazaki, Y., Toriyama, N., Kawakami, S. & Ogawa, T. (2001) J. Geophys. Res.-Atmos., 106,

24 237–24 244.

Thornton, J.A., Wooldridge, P.J. & Cohen, R.C. (2000) Atmospheric NO

: In situ laser-induced

fluorescence detection at parts per trillion mixing ratios, Anal. Chem., 72, 528–539.

Thornton, J.A., Wooldridge, P.J., Cohen, R.C., Martinez, M., Harder, H., Brune, W.H.,

Williams, E.J., Roberts, J.M., Fehsenfeld, F.C., Hall, S.R., Shetter, R.E., Wert, B.P. & Fried, A.

(2002) J. Geophys. Res.-Atmos., 107, 4146.

Thornton, J.A., Wooldridge, P.J., Cohen, R.C., Williams, E.J., Hereid, D., Fehsenfeld, F.C., Stutz, J.

& Alicke, B. (2003) Comparisons of in situ and long path measurements of NO

in urban

plumes, J. Geophys. Res.-Atmos., 108, 4496.

Toohey, D.W., Avallone, L.M., Allen, N.T., Demusz, J.N., Hazen, J.N., Hazen, N.L. & Anderson, J.G.

(1993) Geophys. Res. Lett., 20, 1791–1794.

Tucker, A.W., Birnbaum, M. & Fincher, C.L. (1975) Appl. Opt., 14, 1418–1422.

Vogel, B., Muller, R., Deshler, T., Grooss, J.U., Karhu, J., McKenna, D.S., Muller, M., Toohey, D.,

Toon, G.C. & Stroh, F. (2003) J. Geophys. Res.-Atmos., 108.

Voigt, S., Orphal, J., Burrows, J.P. (2002) The temperature and pressure dependence of the

absorption cross-sections of NO

in the 250–800 nm region measured by Fourier-transform

spectroscopy. J. Photochem. Photobiol. a-Chemistry, 149(1–3), 1–7.

Wang, C.C., Davis, L.I., Wu, C.H. & Japar, S. (1976) Appl. Phys. Lett., 28, 14–16.

Wang, C.C., Davis, L.I., Wu, C.H., Japar, S., Niki, H. & Weinstock, B. (1975) Science, 189, 797–800.

Wang, C.C. & Davis, L.I.J. (1974) Phys. Rev. Lett., 32, 349–352.

Weinstock, B. (1969) Science, 166, 224–225.

Weinstock, E.M., Hintsa, E.J., Dessler, A.E., Oliver, J.F., Hazen, N.L., Demusz, J.N., Allen, N.T.,

Lapson, L.B. & Anderson, J.G. (1994) Rev. Sci. Instrum., 65, 3544–3554.

Wennberg, P.O., Cohen, R.C., Hazen, N.L., Lapson, L.B., Allen, N.T., Hanisco, T.F., Oliver, J.F.,

Lanham, N.W., Demusz, J.N. & Anderson, J.G. (1994a) Rev. Sci. Instrum., 65, 1858–1876.

Wennberg, P.O., Cohen, R.C., Stimpfle, R.M., Koplow, J.P., Anderson, J.G., Salawitch, R.J.,

Fahey, D.W., Woodbridge, E.L., Keim, E.R., Gao, R.S., Webster, C.R., May, R.D., Toohey, D.W.,

Avallone, L.M., Proffitt, M.H., Loewenstein, M., Podolske, J.R., Chan, K.R. & Wofsy, S.C.

(1994b) Science, 266, 398–404.

Wennberg, P.O., Hanisco, T.F., Cohen, R.C., Stimpfle, R.M., Lapson, L.B. & Anderson, J.G. (1995)

In-situ measurements of OH and HO

in the upper troposphere and stratosphere, J. Atmos.

Sci., 52, 3413–3420

Williams, E.J., Baumann, K., Roberts, J.M., Bertman, S.B., Norton, R.B., Fehsenfeld, F.C.,

Springston, S.R., Nunnermacker, L.J., Newman, L., Olszyna, K., Meagher, J., Hartsell, B.,

Edgerton, E., Pearson, J.R. & Rodgers, M.O. (1998) J. Geophys. Res.-Atmos., 103, 22 261–22 280.

Wofsy, S.C., McElroy, M.B. & Yung, Y.L. (1975) Geophys. Res. Lett., 2, 215–218.

Wood, E.C., Wooldridge, P.J., Freese, J.H., Albrecht, T. & Cohen, R.C. (2003) Environ. Sci. Technol.,

37, 5732–5738.

Wood, E.C., Bertram, T.H., Wooldridge, P.J. & Cohen, R.C. (2005) Measurements of N

;NO

and O

east of the San Francisco Bay, Atmospheric Chemistry and Physics, 5, 483–491.

Yokelson, R.J., Burkholder, J.B., Fox, R.W., Talukdar, R.K. & Ravishankara, A.R. (1994) Temper-

ature dependence of the NO

absorption spectrum. J. Phys. Chem., 98(50), 13 144–13 150.

Zhang, Q., Chen, C.X., Yu, S.Q., Ma, X.X. (1998) Kinetic studies on state-state coupling and

collisional quenching of excited sulfur dioxide. Int. J. Chem. Kinet., 30(11), 831–837.

Chapter 5

Mass Spectrometric Methods for

Atmospheric Trace Gases

Jonathan Williams

5.1 Introduction

Mass spectrometry is the most powerful analytical technique available to atmospheric

scientists. Being applicable to all elements, it can provide qualitative and quantitative

information on organic and inorganic species in complex mixtures such as air. The

linearity accuracy and detection limits of mass spectrometry are unequalled in analytical

science, permitting the molecular structures of complex species up to 10

atomic mass

units (dalton) to be determined and attomole 10

−18

 levels to be detected. The technique

is highly versatile and its application in physics, chemistry and biology has led to

key discoveries in all fields. Today, the air we breathe is routinely analysed by mass

spectrometry to determine ambient concentrations of a wide range of compounds,

radicals and isotopes. Such instrumentation can be operated ‘in-situ’ on the ground,

on ships, from aircraft, or even mounted on balloons or rockets. Furthermore mass

spectrometry is also used in the laboratory to investigate key atmospheric reactions or

processes under controlled conditions, as well as to analyse air compressed in containers

or trapped in ice cores. This chapter introduces the fundamentals of trace gas mass

spectrometry (Section 5.2), explains how a mass spectrometer functions (Section 5.3) and

describes instrumentation that is currently being used to explore atmospheric compo-

sition (Section 5.4). Examples are given of some of the results in atmospheric research

and finally future developments in the field are predicted (Section 5.5).

5.1.1 Generating a mass spectrum

Generally speaking we use a mass spectrometer to obtain a ‘mass spectrum’ of the air we

wish to analyse. A mass spectrum provides information on the molecular composition and

abundance in the sample as a function of mass. In the case of ambient air it can tell us the

concentrations of important trace gases such as acetone, hydroxyl radicals or nitric acid

as well as the major constituents such as oxygen. We may even use the mass spectrum to

identify unknown species in the air. To obtain this very useful mass spectrum, we must be

able to sort the air molecules in some way by mass, prior to detection and ideally quantifi-

cation. Intuitively we may think of exploiting the force of gravity to differentiate molecular

masses. However, this force is not strong or tractable enough to effectively mass filter the

sample. Manipulation or filtering of molecules is only possible if the species are ionised

230 Analytical Techniques for Atmospheric Measurement

Ion

source

Ion

accelerator

Mass filter

Ion

detection

system

/ z

Mass spectrum

Air

Figure 5.1 Schematic diagram of a mass spectrometer for air analysis.

or charged, since filtering is achieved by the application of electric and magnetic fields.

The resulting force acting on the species is then proportional to the charge of the species.

By carefully applying these forces to the ionised sample we may segregate the sample

according to the mass-to-charge ratio m/z. Figure 5.1 shows a schematic diagram of a

mass spectrometer used to measure ambient air. The first step is the introduction of the

air into the mass spectrometer. This may be done directly, i.e. inlet 1, or via some form

of pre-separation method such as gas chromatography, inlet 2 (see Chapter 8). Following

the introduction of the sample to the mass spectrometer, the first step in analysis is

ionisation. A range of direct and indirect ionisation methods have been developed for

mass spectrometry and those pertinent to atmospheric trace gas analysis are described in

Section 5.3.1. The ions are then accelerated into a region where electric and magnetic fields

are applied to filter ions by masses allowing them to be separately detected. Several mass

filtering techniques are discussed in Section 5.3.2. After an ion passes through the mass

filter, it enters the detection system, triggering a response that is recorded on a data system.

For quantification, the response of an unknown sample is compared to that of a standard

of known concentration. A summary of the most widespread detector types is given in

Section 5.3.3.

5.1.2 Historical development of the mass spectrometer for

air measurements

A brief history of the development of mass spectrometry is shown in Table 5.1. The first

experiments of J.J. Thompson in 1912 using electric fields to deflect charged particles onto

Mass Spectrometric Methods for Atmospheric Trace Gases 231

Table 5.1 Timeline of developments in mass spectrometry for trace gas analysis in air

1803 Dalton formulates atomic theory – all atoms of the same element have the same mass.

1800s The development of pumps makes it possible to achieve vacuums better than 10

−3

torr.

Vacuum is a critical aspect in mass spectrometry, see Section 5.2.1.

1897 J.J. Thomson discovers electron m/z ratio with combined electric and magnetic ﬁelds.

Receives the Nobel Prize in 1906.

1898 W. Wien analyses anode rays by magnetic deﬂection and establishes their positive charge.

1912 The ﬁrst mass spectra of O

and CO

are recorded by J.J. Thomson.

1919 F.W. Aston develops the ﬁrst mass spectrometer with velocity focussing, and with it

determines mass defects in 1923.

1930s Mattauch–Herzog type magnetic sector instrument developed at the University of Vienna.

1940s Magnetic sector-type instruments used extensively. O.C. Nier used such an instrument in the

Second World War to isolate plutonium, aiding construction of the ﬁrst atomic bomb.

1953 The quadrupole analyser and the ion trap are described by W. Paul and H.S. Steinwedel.

Paul received the Nobel Prize in 1989.

1956 Mass spectrometers are ﬁrst coupled with gas chromatographs by McLafferty and

R.S. Gohlke.

1958 Ions produced in different types of ﬂames measured with a mass spectrometer. (Knewstubb &

Sudgen, 1958).

1963 Ions are ﬁrst detected in the atmosphere.

1966 M.S.B. Munson and F.H. Field develop the principle of chemical ionisation.

1968 First commercial quadrupole instrument is launched by Finnigan.

1975 First commercial GC-MS systems become available with capillary columns.

1977–78 Positive and negative ions are detected for the ﬁrst time in the stratosphere by Arnold and

co-workers (Arnold et al., 1977; Arnold & Henschen, 1978).

1980 Sulphuric acid measured for the ﬁrst time in stratosphere (Arnold & Fabian, 1980).

1984 Acetone detected in upper troposphere/lower stratosphere (Hauck & Arnold, 1984).

1984 First continuous ﬂow isotope ratio mass spectrometer measurements (Barrie et al., 1984).

1985 Antarctic ozone hole discovered by J. Farman.

1987 Isotope mass spectrometer establishes 160 000 year temperature recorded in ice core (Jouzel

et al., 1987).

1989 Nitric acid measurements by atmospheric pressure ionisation mass spectrometer in the

Antarctic vortex and contribute to understanding of ozone hole chemistry (Crutzen & Arnold,

1986).

1998 Proton transfer reaction mass spectrometer launched commercially by Ionicon and ﬁrst

airborne measurements made over the Tropical rainforest (Crutzen et al., 2000).

2003 Fast GC-MS systems developed for aircraft measuring ca 50 species, at picomol levels within

2 minutes (Apel et al., 2003).

2004 Mass spectrometers and air samplers for laboratory analysis by MS are ﬂown

monthly in the upper troposphere and lower stratosphere on commercial airliners,

http://www.caribic-atmospheric.com/.

photographic plates led to the discovery of the electron (Thomson, 1913). Substantial

background material relating to this discovery is available through the London Science

Museum Website http://www.sciencemuseum.org.uk/on-line/electron/section2/index.asp.

Thomson’s student F.W. Aston, in 1919, refined the instrument, which led to the discovery

of isotopes in 1923 (Aston, 1942). Both scientists received Nobel prizes for their work.

Over the following 30 years the technique was rapidly developed and used in diverse fields