Abstract

An iteration method for the determination of size distributions of aerosols from spectral attenuation data, similar to the one previously published for clouds, is presented. The basis for this iteration is to consider the extinction efficiency factor of particles as a set of weighting functions covering the entire radius region of a distribution. The weighting functions were calculated exactly from the Mie theory. Aerosol distributions are shown derived from tests with analytical size distributions and also generated from measured aerosol extinction data in seven spectral channels from 0.4-μ to 10-μ wavelength in continental aerosols. The influence of relative humidity on the complex index of refraction is also discussed.

© 1971 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |
  • |
  • |

  1. H. Grassl, Contr. Atm. Phys. 43, 255 (1970).
  2. G. Yamamoto, M. Tanaka, Appl. Opt. 8, 447 (1969).
    [CrossRef] [PubMed]
  3. K. S. Shifrin, A. Y. Perelman, Tellus 18, 566 (1966).
    [CrossRef]
  4. S. Twomey, H. B. Howell, Appl. Opt. 6, 2125 (1967).
    [CrossRef] [PubMed]
  5. G. N. Plass, G. W. Kattawar, Appl. Opt. 6, 1377 (1967).
    [CrossRef] [PubMed]
  6. K. Fischer, Contr. Atm. Phys. 43, 244 (1970).
  7. D. Deirmendjian, Electromagnetic Scattering on Spherical Polydispersions (Elsevier, New York, 1969).
  8. L. Elterman, AFCRL-68-0153, Environmental Research Papers 285.
  9. P. J. Wyatt, V. R. Stull, G. N. Plass, Final Report SSD-TDR-62-127, Vol. 2, Contract AF 04(695)-96.
  10. K. Bullrich, Adv. Geophysics 10, 99 (1964).
    [CrossRef]
  11. G. Hänel, Contr. Atm. Phys. 43, 119 (1970).

1970

H. Grassl, Contr. Atm. Phys. 43, 255 (1970).

K. Fischer, Contr. Atm. Phys. 43, 244 (1970).

G. Hänel, Contr. Atm. Phys. 43, 119 (1970).

1969

1967

1966

K. S. Shifrin, A. Y. Perelman, Tellus 18, 566 (1966).
[CrossRef]

1964

K. Bullrich, Adv. Geophysics 10, 99 (1964).
[CrossRef]

Bullrich, K.

K. Bullrich, Adv. Geophysics 10, 99 (1964).
[CrossRef]

Deirmendjian, D.

D. Deirmendjian, Electromagnetic Scattering on Spherical Polydispersions (Elsevier, New York, 1969).

Elterman, L.

L. Elterman, AFCRL-68-0153, Environmental Research Papers 285.

Fischer, K.

K. Fischer, Contr. Atm. Phys. 43, 244 (1970).

Grassl, H.

H. Grassl, Contr. Atm. Phys. 43, 255 (1970).

Hänel, G.

G. Hänel, Contr. Atm. Phys. 43, 119 (1970).

Howell, H. B.

Kattawar, G. W.

Perelman, A. Y.

K. S. Shifrin, A. Y. Perelman, Tellus 18, 566 (1966).
[CrossRef]

Plass, G. N.

G. N. Plass, G. W. Kattawar, Appl. Opt. 6, 1377 (1967).
[CrossRef] [PubMed]

P. J. Wyatt, V. R. Stull, G. N. Plass, Final Report SSD-TDR-62-127, Vol. 2, Contract AF 04(695)-96.

Shifrin, K. S.

K. S. Shifrin, A. Y. Perelman, Tellus 18, 566 (1966).
[CrossRef]

Stull, V. R.

P. J. Wyatt, V. R. Stull, G. N. Plass, Final Report SSD-TDR-62-127, Vol. 2, Contract AF 04(695)-96.

Tanaka, M.

Twomey, S.

Wyatt, P. J.

P. J. Wyatt, V. R. Stull, G. N. Plass, Final Report SSD-TDR-62-127, Vol. 2, Contract AF 04(695)-96.

Yamamoto, G.

Adv. Geophysics

K. Bullrich, Adv. Geophysics 10, 99 (1964).
[CrossRef]

Appl. Opt.

Contr. Atm. Phys.

K. Fischer, Contr. Atm. Phys. 43, 244 (1970).

G. Hänel, Contr. Atm. Phys. 43, 119 (1970).

H. Grassl, Contr. Atm. Phys. 43, 255 (1970).

Tellus

K. S. Shifrin, A. Y. Perelman, Tellus 18, 566 (1966).
[CrossRef]

Other

D. Deirmendjian, Electromagnetic Scattering on Spherical Polydispersions (Elsevier, New York, 1969).

L. Elterman, AFCRL-68-0153, Environmental Research Papers 285.

P. J. Wyatt, V. R. Stull, G. N. Plass, Final Report SSD-TDR-62-127, Vol. 2, Contract AF 04(695)-96.

Cited By

OSA participates in CrossRef's Cited-By Linking service. Citing articles from OSA journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (6)

Fig. 1
Fig. 1

Extinction efficiency depending on radius for different wavelength. The curve at the extreme left for 10.4 μ reaches a maximum at about 6-μ radius.

Fig. 2
Fig. 2

Convergence of the iteration for maritime aerosols with a size distribution n(r) = 5.33 · 104 · r · exp (−8.944√r).

Fig. 3
Fig. 3

Variation of the extinction efficiency Q ( r , λ )with the imaginary part of the refractive index.

Fig. 4
Fig. 4

Variation of the extinction efficiency Q ( r , λ )with the real part of the refractive index.

Fig. 5
Fig. 5

Comparison of iterated and exact size distributions. Numbers at the curves correspond to the listed size distributions. At curves 1 and 3 the crosses are the calculated values, at curve 2 circles represent the analytical size distribution, and the dashed curve shows the iterated curve.

Fig. 6
Fig. 6

Size distributions achieved by inversion of measured extinction coefficients for continental aerosols. The dashed curve shows the size distribution from 12 October 1970, the dotted curve for 16 October 1970. For comparison the full line shows a size distribution following a power law with n(r) = C1 · r4.

Tables (3)

Tables Icon

Table I Channels and Associated Radius Regions (μ)

Tables Icon

Table II Extinction Coefficients for Maritime and Cotinental Aerosol Size Distributionsa

Tables Icon

Table III Measured Aerosol Extinction Coefficients kλ per Air Mass and Associated Size Distributions n(r) in Relative Units Generated by Inversion of the Extinction Coefficients kλ

Equations (9)

Equations on this page are rendered with MathJax. Learn more.

k λ = π r 1 r 2 Q ( r , λ ) · n ( r ) · r 2 · d r
Q ( r , λ ) ,
Q ( r , λ )
Q ( r , λ )
Q ( r , λ )
n 1 ( r ¯ i ) = ( k i / k 0 i ) n 0 ( r ¯ i )             i = 1 , m .
( 1 ) n ( r ) = 5.33 · 10 4 · r · exp ( - 8.994 r ¯ ) maritime aerosol ( 2 ) ( 3 ) n ( r ) = C 1 · r - 4 n ( r ) = C 2 · r - 3 } continental aerosols ,
Q ( r , λ )
Q ( r , λ )

Metrics