Abstract

A comprehensive analytical radiative transfer model for isothermal aerosols and vapors for passive infrared remote sensing applications (ground-based and airborne sensors) has been developed. The theoretical model illustrates the qualitative difference between an aerosol cloud and a chemical vapor cloud. The model is based on two and two∕four stream approximations and includes thermal emission–absorption by the aerosols; scattering of diffused sky radiances incident from all sides on the aerosols (downwelling, upwelling, left, and right); and scattering of aerosol thermal emission. The model uses moderate resolution transmittance ambient atmospheric radiances as boundary conditions and provides analytical expressions for the information on the aerosol cloud that is contained in remote sensing measurements by using thermal contrasts between the aerosols and diffused sky radiances. Simulated measurements of a ground-based sensor viewing Bacillus subtilis var. niger bioaerosols and kaolin aerosols are given and discussed to illustrate the differences between a vapor-only model (i.e., only emission–absorption effects) and a complete model that adds aerosol scattering effects.

© 2006 Optical Society of America

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    [CrossRef]

2005 (2)

F. M. D'Amico, R. P. Moon, and C. E. Davidson, "Aerosol identification using a hybrid active/passive system," in Lidar Remote Sensing for Environment Monitoring VI, U. N. Singh, ed., Proc. SPIE 5887, 149-157 (2005).

A. Ben-David and H. Ren, "Comparison between orthogonal subspace projection and background subtraction techniques applied to remote-sensing data," Appl. Opt. 44, 3846-3855 (2005).
[CrossRef]

2003 (5)

A. Ben-David, A. Ifarraguerri, and A Samuels, "Correlation spectroscopy with diffractive grating synthetic spectra and orthogonal subspace projection (OSP) filters," Opt. Eng. 42, 325-333 (2003).
[CrossRef]

A. Ben-David, "Remote detection of biological aerosols at a distance of 3 km with a passive Fourier transform infrared (FTIR) sensor," Opt. Express 11, 418-429 (2003).

A. Ben-David and H. Ren, "Detection, identification and estimation of biological aerosols and vapors with Fourier transform infrared spectrometer," Appl. Opt. 42, 4887-4900 (2003).

J. M. Therault, E. Puckrin, and J. O. Jensen, "Passive standoff detection of Bacillus subtilis aerosol by Fourier transform infrared radiometry," Appl. Opt. 42, 6696-6703 (2003).

F. M. D'Amico, D. K. Emge, and G. Roelant, "Outdoor chamber measurements of biological aerosols with passive FTIR spectrometer," in Chemical and Biological Standoff Detection, J. O. Jenson and J.-M. Therault, eds., Proc. SPIE 5268, 173-183 (2003).
[CrossRef]

2002 (1)

2001 (1)

R. A. Sutherland, J. C. Thompson, and S. D. Ayres, "Infrared scene modeling in emissive, absorptive, and multiple scattering atmospheres," in Targets and Backgrounds VII: Characterization and Representation, W. R. Watkins, D. Clement, and R. R. Reynolds, eds., Proc. SPIE 4370, 210-219 (2001).
[CrossRef]

2000 (1)

R. A. Sutherland, J. C. Thompson, and J. D. Klett, "Effects of multiple scattering and thermal emission on target-background signatures sensed through obscuring atmospheres," in Targets and Backgrounds VI: Characterization, Visualization, and the Detection Process, W. R. Watkins, D. Clement, and R. R. Reynolds, eds., Proc. SPIE 4029, 300-309 (2000).
[CrossRef]

1999 (1)

A. Berk, G. P. Anderson, L. S. Bernstein, P. K. Acharya, H. Dothe, M. W. Matthew, S. M. Adler-Golden, J. H. Chetwynd, Jr., S. C. Richtsmeier, B. Pukall, C. L. Allred, L. S. Jeong, and M. L. Hoke, "MODTRAN4 radiative transfer modeling for atmospheric correction," in Optical Spectroscopic Techniques and Instrumentation for Atmospheric and Space Research III, A. M. Larar, ed., Proc. SPIE 3756, 348-353 (1999).
[CrossRef]

1997 (1)

Q. Fu, K. N. Liou, M. C. Cribb, T. P. Charlock, and A. Grossman, "Multiple scattering parametrization in thermal infrared radiative transfer," J. Atmos. Sci. 54, 2799-2812 (1997).
[CrossRef]

1996 (1)

1995 (3)

1994 (1)

1989 (1)

O. B. Toon, C. P. Mckay, and T. P. Ackerman, "Rapid calculation of radiative heating rates and photodissociation rates in inhomogeneous multiple scattering atmospheres," J. Geophys. Res. 94, 16287-16301 (1989).

1987 (1)

1980 (2)

W. E. Meador and W. R. Weaver, "Two-stream approximations to radiative transfer in planetary atmospheres: a unified description of existing methods and new improvement," J. Atmos. Sci. 37, 630-643 (1980).
[CrossRef]

A. Ben-Shalom, B. Brazilai, D. Cabib, A. D. Devir, S. G. Lipson, and U. P. Oppenheim, "Sky radiance at wavelengths between 7 and 14 μm: measurements, calculation, and comparison with LOWTRAN-4 predictions," Appl. Opt. 19, 838-839 (1980).

1965 (1)

B. M. Herman and S. R. Browning, "A numerical solution to the equation of radiative transfer," J. Atmos. Sci. 32, 559-566 (1965).
[CrossRef]

Acharya, P. K.

A. Berk, G. P. Anderson, L. S. Bernstein, P. K. Acharya, H. Dothe, M. W. Matthew, S. M. Adler-Golden, J. H. Chetwynd, Jr., S. C. Richtsmeier, B. Pukall, C. L. Allred, L. S. Jeong, and M. L. Hoke, "MODTRAN4 radiative transfer modeling for atmospheric correction," in Optical Spectroscopic Techniques and Instrumentation for Atmospheric and Space Research III, A. M. Larar, ed., Proc. SPIE 3756, 348-353 (1999).
[CrossRef]

Ackerman, T. P.

O. B. Toon, C. P. Mckay, and T. P. Ackerman, "Rapid calculation of radiative heating rates and photodissociation rates in inhomogeneous multiple scattering atmospheres," J. Geophys. Res. 94, 16287-16301 (1989).

Adler-Golden, S. M.

A. Berk, G. P. Anderson, L. S. Bernstein, P. K. Acharya, H. Dothe, M. W. Matthew, S. M. Adler-Golden, J. H. Chetwynd, Jr., S. C. Richtsmeier, B. Pukall, C. L. Allred, L. S. Jeong, and M. L. Hoke, "MODTRAN4 radiative transfer modeling for atmospheric correction," in Optical Spectroscopic Techniques and Instrumentation for Atmospheric and Space Research III, A. M. Larar, ed., Proc. SPIE 3756, 348-353 (1999).
[CrossRef]

Allred, C. L.

A. Berk, G. P. Anderson, L. S. Bernstein, P. K. Acharya, H. Dothe, M. W. Matthew, S. M. Adler-Golden, J. H. Chetwynd, Jr., S. C. Richtsmeier, B. Pukall, C. L. Allred, L. S. Jeong, and M. L. Hoke, "MODTRAN4 radiative transfer modeling for atmospheric correction," in Optical Spectroscopic Techniques and Instrumentation for Atmospheric and Space Research III, A. M. Larar, ed., Proc. SPIE 3756, 348-353 (1999).
[CrossRef]

Anderson, G. P.

A. Berk, G. P. Anderson, L. S. Bernstein, P. K. Acharya, H. Dothe, M. W. Matthew, S. M. Adler-Golden, J. H. Chetwynd, Jr., S. C. Richtsmeier, B. Pukall, C. L. Allred, L. S. Jeong, and M. L. Hoke, "MODTRAN4 radiative transfer modeling for atmospheric correction," in Optical Spectroscopic Techniques and Instrumentation for Atmospheric and Space Research III, A. M. Larar, ed., Proc. SPIE 3756, 348-353 (1999).
[CrossRef]

Astarita, J.

D. F. Flanigan and J. Astarita, "Low angle sky DT from MODTRAN atmospheric models," in Third Workshop on Stand-Off Detection for Chemical and Biological Defense, Williamsburg, Va. (1994), pp. 397-408.

Ayres, S. D.

R. A. Sutherland, J. C. Thompson, and S. D. Ayres, "Infrared scene modeling in emissive, absorptive, and multiple scattering atmospheres," in Targets and Backgrounds VII: Characterization and Representation, W. R. Watkins, D. Clement, and R. R. Reynolds, eds., Proc. SPIE 4370, 210-219 (2001).
[CrossRef]

Ben-David, A.

Ben-Shalom, A.

Berk, A.

A. Berk, G. P. Anderson, L. S. Bernstein, P. K. Acharya, H. Dothe, M. W. Matthew, S. M. Adler-Golden, J. H. Chetwynd, Jr., S. C. Richtsmeier, B. Pukall, C. L. Allred, L. S. Jeong, and M. L. Hoke, "MODTRAN4 radiative transfer modeling for atmospheric correction," in Optical Spectroscopic Techniques and Instrumentation for Atmospheric and Space Research III, A. M. Larar, ed., Proc. SPIE 3756, 348-353 (1999).
[CrossRef]

Bernstein, L. S.

A. Berk, G. P. Anderson, L. S. Bernstein, P. K. Acharya, H. Dothe, M. W. Matthew, S. M. Adler-Golden, J. H. Chetwynd, Jr., S. C. Richtsmeier, B. Pukall, C. L. Allred, L. S. Jeong, and M. L. Hoke, "MODTRAN4 radiative transfer modeling for atmospheric correction," in Optical Spectroscopic Techniques and Instrumentation for Atmospheric and Space Research III, A. M. Larar, ed., Proc. SPIE 3756, 348-353 (1999).
[CrossRef]

Boreman, G. D.

E. L. Dereniak and G. D. Boreman, Infrared Detectors and Systems (Wiley, 1996).

Brazilai, B.

Browning, S. R.

B. M. Herman and S. R. Browning, "A numerical solution to the equation of radiative transfer," J. Atmos. Sci. 32, 559-566 (1965).
[CrossRef]

Cabib, D.

Caudill, T. R.

Chandrasekhar, S.

S. Chandrasekhar, Radiative Transfer (Dover, 1960).

Charlock, T. P.

Q. Fu, K. N. Liou, M. C. Cribb, T. P. Charlock, and A. Grossman, "Multiple scattering parametrization in thermal infrared radiative transfer," J. Atmos. Sci. 54, 2799-2812 (1997).
[CrossRef]

Chetwynd, J. H.

A. Berk, G. P. Anderson, L. S. Bernstein, P. K. Acharya, H. Dothe, M. W. Matthew, S. M. Adler-Golden, J. H. Chetwynd, Jr., S. C. Richtsmeier, B. Pukall, C. L. Allred, L. S. Jeong, and M. L. Hoke, "MODTRAN4 radiative transfer modeling for atmospheric correction," in Optical Spectroscopic Techniques and Instrumentation for Atmospheric and Space Research III, A. M. Larar, ed., Proc. SPIE 3756, 348-353 (1999).
[CrossRef]

Cosofret, B. C.

W. J. Marinelli, C. M. Gittins, B. C. Cosofret, and T. E. Ustun, "AIRIS wide area detector system field tests," in Proceedings of the Sixth Joint Conference for Standoff Detection and Biological Defense, Williamsburg, Va. (2004).

Cribb, M. C.

Q. Fu, K. N. Liou, M. C. Cribb, T. P. Charlock, and A. Grossman, "Multiple scattering parametrization in thermal infrared radiative transfer," J. Atmos. Sci. 54, 2799-2812 (1997).
[CrossRef]

D'Amico, F. M.

F. M. D'Amico, R. P. Moon, and C. E. Davidson, "Aerosol identification using a hybrid active/passive system," in Lidar Remote Sensing for Environment Monitoring VI, U. N. Singh, ed., Proc. SPIE 5887, 149-157 (2005).

F. M. D'Amico, D. K. Emge, and G. Roelant, "Outdoor chamber measurements of biological aerosols with passive FTIR spectrometer," in Chemical and Biological Standoff Detection, J. O. Jenson and J.-M. Therault, eds., Proc. SPIE 5268, 173-183 (2003).
[CrossRef]

Davidson, C. E.

F. M. D'Amico, R. P. Moon, and C. E. Davidson, "Aerosol identification using a hybrid active/passive system," in Lidar Remote Sensing for Environment Monitoring VI, U. N. Singh, ed., Proc. SPIE 5887, 149-157 (2005).

Dereniak, E. L.

E. L. Dereniak and G. D. Boreman, Infrared Detectors and Systems (Wiley, 1996).

Devir, A. D.

Dothe, H.

A. Berk, G. P. Anderson, L. S. Bernstein, P. K. Acharya, H. Dothe, M. W. Matthew, S. M. Adler-Golden, J. H. Chetwynd, Jr., S. C. Richtsmeier, B. Pukall, C. L. Allred, L. S. Jeong, and M. L. Hoke, "MODTRAN4 radiative transfer modeling for atmospheric correction," in Optical Spectroscopic Techniques and Instrumentation for Atmospheric and Space Research III, A. M. Larar, ed., Proc. SPIE 3756, 348-353 (1999).
[CrossRef]

Elsasser, W. M.

W. M. Elsasser, Heat Transfer by Infrared Radiation in the Atmosphere, in Harvard Meteorological Studies (Harvard U. Press, 1942), Vol. 6, p. 107.

Emge, D. K.

F. M. D'Amico, D. K. Emge, and G. Roelant, "Outdoor chamber measurements of biological aerosols with passive FTIR spectrometer," in Chemical and Biological Standoff Detection, J. O. Jenson and J.-M. Therault, eds., Proc. SPIE 5268, 173-183 (2003).
[CrossRef]

Flanigan, D. F.

D. F. Flanigan, "Prediction of the limits of detection of hazardous vapors by passive infrared with the use of MODTRAN," Appl. Opt. 35, 6090-6098 (1996).

D. F. Flanigan and J. Astarita, "Low angle sky DT from MODTRAN atmospheric models," in Third Workshop on Stand-Off Detection for Chemical and Biological Defense, Williamsburg, Va. (1994), pp. 397-408.

Flittner, D. E.

Fu, Q.

Q. Fu, K. N. Liou, M. C. Cribb, T. P. Charlock, and A. Grossman, "Multiple scattering parametrization in thermal infrared radiative transfer," J. Atmos. Sci. 54, 2799-2812 (1997).
[CrossRef]

Gittins, C. M.

W. J. Marinelli, C. M. Gittins, B. C. Cosofret, and T. E. Ustun, "AIRIS wide area detector system field tests," in Proceedings of the Sixth Joint Conference for Standoff Detection and Biological Defense, Williamsburg, Va. (2004).

W. J. Marinelli, C. M. Gittins, and T. E. Ustun, "AIRIS wide area detection system," in Proceedings of the 2002 Joint Service Scientific Conference on Chemical and Biological Defense Research, 19-21 November 2002, D.A.Berg, ed., (ECBC-SP-015, 2003).

Goldberg, S.

Grossman, A.

Q. Fu, K. N. Liou, M. C. Cribb, T. P. Charlock, and A. Grossman, "Multiple scattering parametrization in thermal infrared radiative transfer," J. Atmos. Sci. 54, 2799-2812 (1997).
[CrossRef]

Hall, J. L.

Herman, B. M.

Herr, K. C.

Hoke, M. L.

A. Berk, G. P. Anderson, L. S. Bernstein, P. K. Acharya, H. Dothe, M. W. Matthew, S. M. Adler-Golden, J. H. Chetwynd, Jr., S. C. Richtsmeier, B. Pukall, C. L. Allred, L. S. Jeong, and M. L. Hoke, "MODTRAN4 radiative transfer modeling for atmospheric correction," in Optical Spectroscopic Techniques and Instrumentation for Atmospheric and Space Research III, A. M. Larar, ed., Proc. SPIE 3756, 348-353 (1999).
[CrossRef]

Ifarraguerri, A.

A. Ben-David, A. Ifarraguerri, and A Samuels, "Correlation spectroscopy with diffractive grating synthetic spectra and orthogonal subspace projection (OSP) filters," Opt. Eng. 42, 325-333 (2003).
[CrossRef]

Issacs, R. G.

Jensen, J. O.

Jeong, L. S.

A. Berk, G. P. Anderson, L. S. Bernstein, P. K. Acharya, H. Dothe, M. W. Matthew, S. M. Adler-Golden, J. H. Chetwynd, Jr., S. C. Richtsmeier, B. Pukall, C. L. Allred, L. S. Jeong, and M. L. Hoke, "MODTRAN4 radiative transfer modeling for atmospheric correction," in Optical Spectroscopic Techniques and Instrumentation for Atmospheric and Space Research III, A. M. Larar, ed., Proc. SPIE 3756, 348-353 (1999).
[CrossRef]

Klett, J. D.

R. A. Sutherland, J. C. Thompson, and J. D. Klett, "Effects of multiple scattering and thermal emission on target-background signatures sensed through obscuring atmospheres," in Targets and Backgrounds VI: Characterization, Visualization, and the Detection Process, W. R. Watkins, D. Clement, and R. R. Reynolds, eds., Proc. SPIE 4029, 300-309 (2000).
[CrossRef]

Laufer, G.

Lenoble, J.

J. Lenoble, Radiative Transfer in Scattering and Absorbing Atmospheres: Standard Computational Procedures (Deepak, 1985).

Liou, K. N.

Q. Fu, K. N. Liou, M. C. Cribb, T. P. Charlock, and A. Grossman, "Multiple scattering parametrization in thermal infrared radiative transfer," J. Atmos. Sci. 54, 2799-2812 (1997).
[CrossRef]

K. N. Liou, Radiation and Cloud Processes in the Atmosphere (Oxford U. Press, 1992).

K. N. Liou, An Introduction to Atmospheric Radiation, 2nd ed. (Academic, 2002).

Lioyd, J. M.

J. M. Lioyd, Thermal Imaging System (Plenum, 1975).

Lipson, S. G.

Marinelli, W. J.

W. J. Marinelli, C. M. Gittins, and T. E. Ustun, "AIRIS wide area detection system," in Proceedings of the 2002 Joint Service Scientific Conference on Chemical and Biological Defense Research, 19-21 November 2002, D.A.Berg, ed., (ECBC-SP-015, 2003).

W. J. Marinelli, C. M. Gittins, B. C. Cosofret, and T. E. Ustun, "AIRIS wide area detector system field tests," in Proceedings of the Sixth Joint Conference for Standoff Detection and Biological Defense, Williamsburg, Va. (2004).

Matthew, M. W.

A. Berk, G. P. Anderson, L. S. Bernstein, P. K. Acharya, H. Dothe, M. W. Matthew, S. M. Adler-Golden, J. H. Chetwynd, Jr., S. C. Richtsmeier, B. Pukall, C. L. Allred, L. S. Jeong, and M. L. Hoke, "MODTRAN4 radiative transfer modeling for atmospheric correction," in Optical Spectroscopic Techniques and Instrumentation for Atmospheric and Space Research III, A. M. Larar, ed., Proc. SPIE 3756, 348-353 (1999).
[CrossRef]

Mckay, C. P.

O. B. Toon, C. P. Mckay, and T. P. Ackerman, "Rapid calculation of radiative heating rates and photodissociation rates in inhomogeneous multiple scattering atmospheres," J. Geophys. Res. 94, 16287-16301 (1989).

Meador, W. E.

W. E. Meador and W. R. Weaver, "Two-stream approximations to radiative transfer in planetary atmospheres: a unified description of existing methods and new improvement," J. Atmos. Sci. 37, 630-643 (1980).
[CrossRef]

Moon, R. P.

F. M. D'Amico, R. P. Moon, and C. E. Davidson, "Aerosol identification using a hybrid active/passive system," in Lidar Remote Sensing for Environment Monitoring VI, U. N. Singh, ed., Proc. SPIE 5887, 149-157 (2005).

Oppenheim, U. P.

Polak, M. L.

Puckrin, E.

Pukall, B.

A. Berk, G. P. Anderson, L. S. Bernstein, P. K. Acharya, H. Dothe, M. W. Matthew, S. M. Adler-Golden, J. H. Chetwynd, Jr., S. C. Richtsmeier, B. Pukall, C. L. Allred, L. S. Jeong, and M. L. Hoke, "MODTRAN4 radiative transfer modeling for atmospheric correction," in Optical Spectroscopic Techniques and Instrumentation for Atmospheric and Space Research III, A. M. Larar, ed., Proc. SPIE 3756, 348-353 (1999).
[CrossRef]

Ren, H.

Richtsmeier, S. C.

A. Berk, G. P. Anderson, L. S. Bernstein, P. K. Acharya, H. Dothe, M. W. Matthew, S. M. Adler-Golden, J. H. Chetwynd, Jr., S. C. Richtsmeier, B. Pukall, C. L. Allred, L. S. Jeong, and M. L. Hoke, "MODTRAN4 radiative transfer modeling for atmospheric correction," in Optical Spectroscopic Techniques and Instrumentation for Atmospheric and Space Research III, A. M. Larar, ed., Proc. SPIE 3756, 348-353 (1999).
[CrossRef]

Roelant, G.

F. M. D'Amico, D. K. Emge, and G. Roelant, "Outdoor chamber measurements of biological aerosols with passive FTIR spectrometer," in Chemical and Biological Standoff Detection, J. O. Jenson and J.-M. Therault, eds., Proc. SPIE 5268, 173-183 (2003).
[CrossRef]

Samuels, A

A. Ben-David, A. Ifarraguerri, and A Samuels, "Correlation spectroscopy with diffractive grating synthetic spectra and orthogonal subspace projection (OSP) filters," Opt. Eng. 42, 325-333 (2003).
[CrossRef]

Sutherland, R. A.

R. A. Sutherland, J. C. Thompson, and S. D. Ayres, "Infrared scene modeling in emissive, absorptive, and multiple scattering atmospheres," in Targets and Backgrounds VII: Characterization and Representation, W. R. Watkins, D. Clement, and R. R. Reynolds, eds., Proc. SPIE 4370, 210-219 (2001).
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R. A. Sutherland, J. C. Thompson, and J. D. Klett, "Effects of multiple scattering and thermal emission on target-background signatures sensed through obscuring atmospheres," in Targets and Backgrounds VI: Characterization, Visualization, and the Detection Process, W. R. Watkins, D. Clement, and R. R. Reynolds, eds., Proc. SPIE 4029, 300-309 (2000).
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Therault, J. M.

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R. A. Sutherland, J. C. Thompson, and S. D. Ayres, "Infrared scene modeling in emissive, absorptive, and multiple scattering atmospheres," in Targets and Backgrounds VII: Characterization and Representation, W. R. Watkins, D. Clement, and R. R. Reynolds, eds., Proc. SPIE 4370, 210-219 (2001).
[CrossRef]

R. A. Sutherland, J. C. Thompson, and J. D. Klett, "Effects of multiple scattering and thermal emission on target-background signatures sensed through obscuring atmospheres," in Targets and Backgrounds VI: Characterization, Visualization, and the Detection Process, W. R. Watkins, D. Clement, and R. R. Reynolds, eds., Proc. SPIE 4029, 300-309 (2000).
[CrossRef]

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Ustun, T. E.

W. J. Marinelli, C. M. Gittins, B. C. Cosofret, and T. E. Ustun, "AIRIS wide area detector system field tests," in Proceedings of the Sixth Joint Conference for Standoff Detection and Biological Defense, Williamsburg, Va. (2004).

W. J. Marinelli, C. M. Gittins, and T. E. Ustun, "AIRIS wide area detection system," in Proceedings of the 2002 Joint Service Scientific Conference on Chemical and Biological Defense Research, 19-21 November 2002, D.A.Berg, ed., (ECBC-SP-015, 2003).

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O. B. Toon, C. P. Mckay, and T. P. Ackerman, "Rapid calculation of radiative heating rates and photodissociation rates in inhomogeneous multiple scattering atmospheres," J. Geophys. Res. 94, 16287-16301 (1989).

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F. M. D'Amico, R. P. Moon, and C. E. Davidson, "Aerosol identification using a hybrid active/passive system," in Lidar Remote Sensing for Environment Monitoring VI, U. N. Singh, ed., Proc. SPIE 5887, 149-157 (2005).

F. M. D'Amico, D. K. Emge, and G. Roelant, "Outdoor chamber measurements of biological aerosols with passive FTIR spectrometer," in Chemical and Biological Standoff Detection, J. O. Jenson and J.-M. Therault, eds., Proc. SPIE 5268, 173-183 (2003).
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R. A. Sutherland, J. C. Thompson, and J. D. Klett, "Effects of multiple scattering and thermal emission on target-background signatures sensed through obscuring atmospheres," in Targets and Backgrounds VI: Characterization, Visualization, and the Detection Process, W. R. Watkins, D. Clement, and R. R. Reynolds, eds., Proc. SPIE 4029, 300-309 (2000).
[CrossRef]

R. A. Sutherland, J. C. Thompson, and S. D. Ayres, "Infrared scene modeling in emissive, absorptive, and multiple scattering atmospheres," in Targets and Backgrounds VII: Characterization and Representation, W. R. Watkins, D. Clement, and R. R. Reynolds, eds., Proc. SPIE 4370, 210-219 (2001).
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W. J. Marinelli, C. M. Gittins, and T. E. Ustun, "AIRIS wide area detection system," in Proceedings of the 2002 Joint Service Scientific Conference on Chemical and Biological Defense Research, 19-21 November 2002, D.A.Berg, ed., (ECBC-SP-015, 2003).

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W. J. Marinelli, C. M. Gittins, B. C. Cosofret, and T. E. Ustun, "AIRIS wide area detector system field tests," in Proceedings of the Sixth Joint Conference for Standoff Detection and Biological Defense, Williamsburg, Va. (2004).

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Figures (8)

Fig. 1
Fig. 1

Notations for radiances in two∕stream and two∕four-stream radiative transfer models (see text).

Fig. 2
Fig. 2

LOS geometry for looking-up and looking-down geometries viewing a rectangular cloud within diffuse radiation fields D, U, L, and R. The cloud is at a height z above the ground and at a distance x from a ground-based sensor looking up with LOS1.

Fig. 3
Fig. 3

Angles μ D & U and μ L & R for the radiances I D & U and I L & R , respectively, for LOS looking up and looking down.

Fig. 4
Fig. 4

MODTRAN angles (variable ANGLE in MODTRAN card #3) θ D , θ U , θ L , and θ R (54.7°, 125.3°, 35.3°, and 144.7°, respectively) for computing the diffuse radiances D ( μ 1 ) , U ( μ 1 ) , L ( μ 1 ) , and R ( μ 1 ) with MODTRAN.

Fig. 5
Fig. 5

Diffused atmospheric radiances D ( μ 1 ) , U ( μ 1 ) , L ( μ 1 ) , and R ( μ 1 ) where the ground is a blackbody with 0.85 emissivity and a temperature of 298.15 K, the cloud blackbody radiance B ( T = 288.15 K ) , and the radiance L ( μ L & R ) at the cloud location (i.e., 9 km from the topographical target) due to LOS pointing toward the topographical target (0.85 emissivity and temperature of 294.94 K ) .

Fig. 6
Fig. 6

Optical parameters and the portion of the signal ( Δ M thermal , Δ M scatter ) in the measurement of a rectangular ( 100 m × 50 m ) BG aerosol cloud at ambient temperature with a concentration of 10 3 cm 3 and a lognormal size distribution in a U.S. 1976 standard atmosphere (see Fig. 5) viewed by a passive IR sensor with a LOS looking up at a near grazing angle of 85° toward a topographical target at 10 km. (a) Optical properties: optical depth τ, asymmetry parameter g, and single-scattering albedo ϖ for an aerosol layer 100 m thick. (b) Portion of the measurements that contain information on the presence of the cloud: Δ M thermal due to emission, Δ M scatter due to scattering, and Δ M total = Δ M thermal + Δ M scatter .

Fig. 7
Fig. 7

Same as Fig. 6 but for a cloud of kaolin aerosols.

Fig. 8
Fig. 8

Radiance B scat from thermally emitted photons by the aerosol's layer of thickness x = 100 m that are scattered upward, and its magnitude with respect to the thermal emission 0 B e - τ / μ 1 ( 1 - ϖ ) B ( 1 - ϖ ) within the aerosol layer. The aerosols are at a temperature of 288.15 K , with a lognormal size distribution and a concentration of 10 3 cm 3 (same as for Figs. 6 and 7). (a) BG aerosols, (b) kaolin aerosols.

Equations (57)

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μ d I ( τ , μ ) d τ = I ( τ , μ ) S ( τ , μ ) .
S ( τ , μ ) = ϖ 2 - 1 1 P ( μ , μ ) I ( τ , μ ) d μ + ( 1 ϖ ) B ( T ) .
P ( μ , μ ) = ( 1 + 3 g μ μ ) δ ( μ ± μ 1 ) δ ( μ ± μ 1 ) ,
μ 1 d I ( τ , μ 1 ) d τ = [ 1 ϖ ( 1 + g ) 2 ] I ( τ , μ 1 ) ϖ ( 1 g ) 2 I ( τ , μ 1 ) ( 1 ϖ ) B ,
μ 1 d I ( τ , μ 1 ) d τ = ϖ ( 1 g ) 2 I ( τ , μ 1 ) [ 1 ϖ ( 1 + g ) 2 ] I ( τ , μ 1 ) + ( 1 ϖ ) B .
I ( τ , μ ; τ 1 ) = { I ( τ ) δ ( μ μ 1 ) = I ( τ , μ 1 ; τ 1 ) = r ( τ ; τ 1 ) D ( μ 1 ) + t ( τ ; τ 1 ) U ( μ 1 ) + ξ ( τ ; τ 1 ) B , upward, I ( τ ) δ ( μ + μ 1 ) = I ( τ , μ 1 ; τ 1 ) = t ( τ ; τ 1 ) D ( μ 1 ) + r ( τ ; τ 1 ) U ( μ 1 ) + ξ ( τ ; τ 1 ) B , downward } ,
t ( τ ; τ 1 ) = e k ( τ 1 τ ) a 2 e k ( τ 1 + τ ) 1 a 2 e 2 k τ 1 ,
r ( τ ; τ 1 ) = a [ e k τ e k ( 2 τ 1 τ ) ] 1 a 2 e 2 k τ 1 ,
ξ ( τ ; τ 1 ) = 1 e k ( τ 1 τ ) + a ( e k τ 1 e k τ ) 1 + a e k τ 1
= 1 r ( τ ; τ 1 ) t ( τ ; τ 1 )
t ( τ ; τ 1 ) = e k τ a 2 e k ( 2 τ 1 τ ) 1 a 2 e 2 k τ 1 ,
r ( τ ; τ 1 ) = a [ e k ( τ 1 τ ) e k ( τ 1 + τ ) ] 1 a 2 e 2 k τ 1 ,
ξ ( τ ; τ 1 ) = 1 e k τ + a [ e k τ 1 e k ( τ 1 τ ) ] 1 + a e k τ 1
= 1 r ( τ ; τ 1 ) t ( τ ; τ 1 )
k = ( 1 ϖ ) ( 1 ϖ g ) μ 1
a = 1 ϖ ( 1 + g ) / 2 ( 1 ϖ ) ( 1 ϖ g ) ϖ ( 1 g ) / 2 .
I ( τ , μ 1 ; τ 1 ) = D ( μ 1 ) top bot + U ( μ 1 ) bot + ( 1 bot bot ) B + ( 1 top top ) bot B 1 top bot , upward,
I ( τ , μ 1 ; τ 1 ) = D ( μ 1 ) top + U ( μ 1 ) bot top + ( 1 top top ) B + ( 1 bot bot ) top B 1 top bot , downward ,
t ( τ ; τ 1 ) = bot 1 top bot ,
r ( τ ; τ 1 ) = top bot 1 top bot ,
ξ ( τ ; τ 1 ) = 1 bot top bot top bot 1 top bot
= 1 r ( τ ; τ 1 ) t ( τ ; τ 1 ) ,
t ( τ ; τ 1 ) = top 1 top bot ,
r ( τ ; τ 1 ) = bot top 1 top bot ,
ξ ( τ ; τ 1 ) = 1 top bot top bot top 1 top bot ,
= 1 r ( τ ; τ 1 ) t ( τ ; τ 1 ) ,
bot = t 1 r r t t ; bot = r t ,
top = t 1 r r t t ; top = r t .
I ( top,   τ 1 < ∼ 0.1 ) = r D ( μ 1 ) + t U ( μ 1 ) + ξ B ,
I ( bottom,   τ 1 < 0.1 ) = t D ( μ 1 ) + r U ( μ 1 ) + ξ B ,
t = 1 1 ϖ ( 1 + g ) / 2 μ 1 τ 1 , r = ϖ ( 1 g ) / 2 μ 1 τ 1 , ξ = 1 ϖ μ 1 τ 1 = 1 r t .
S ( τ , μ ; τ 1 ) = { S ( τ , μ ) δ ( μ μ 1 ) = S ( τ , μ 1 ; τ 1 )   = r s ( τ ; τ 1 ) D ( μ 1 ) + t s ( τ ; τ 1 ) U ( μ 1 ) + ξ s ( τ ; τ 1 ) B , upward , S ( τ , μ ) δ ( μ + μ 1 ) = S ( τ , μ 1 ; τ )   = t s ( τ ; τ 1 ) D ( μ 1 ) + r s ( τ ; τ 1 ) U ( μ 1 ) + ξ s ( τ ; τ 1 ) B , downward } ,
t s ( τ ; τ 1 ) = e k ( τ 1 τ ) ( 1 μ 1 k ) a 2 e k ( τ 1 + τ ) ( 1 + μ 1 k ) 1 a 2 e 2 k τ 1 ,
r s ( τ ; τ 1 ) = a e ( 1 + μ 1 k ) a e k ( 2 τ 1 τ ) ( 1 μ 1 k ) 1 a 2 e 2 k τ 1 ,
ξ s ( τ ; τ 1 ) = 1 + a e k τ 1 a e k τ ( 1 + μ 1 k ) e k ( τ 1 τ ) ( 1 μ 1 k ) 1 + a e k τ 1
= 1 r s ( τ ; τ 1 ) t s ( τ ; τ 1 ) ,
t s ( τ ; τ 1 ) = e k τ ( 1 μ 1 k ) a 2 e k ( 2 τ 1 τ ) ( 1 + μ 1 k ) 1 a 2 e 2 k τ 1 ,
r s ( τ ; τ 1 ) = a e k ( τ 1 τ ) ( 1 + μ 1 k ) a e k ( τ 1 + τ ) ( 1 μ 1 k ) 1 a 2 e 2 k τ 1 ,
ξ s ( τ ; τ 1 ) = 1 + a e k τ 1 a e k ( τ 1 τ ) ( 1 + μ 1 k ) e k τ ( 1 μ 1 k ) 1 + a e k τ 1
= 1 r s ( τ ; τ 1 ) t s ( τ ; τ 1 ) .
ξ s ( τ ; τ 1 ) 1 ϖ = Q scat ( τ ; τ 1 ) > 1 , ξ s ( τ ; τ 1 ) 1 ϖ = Q scat ( τ ; τ 1 ) > 1.
B scat = [ Q scat ( τ ; τ 1 ) 1 ] ( 1 ϖ ) B ( T ) d τ , upward, B scat = ( Q scat ( τ ; τ 1 ) 1 ) ( 1 ϖ ) B ( T ) d τ , downward .
I ( 0 , μ ; τ 1 ) = U ( μ ) e τ / μ + 0 τ 1 S ( τ , μ 1 ) e τ / μ d τ μ , upward   at   top, I ( τ 1 , − μ ; τ 1 ) = D ( μ ) e τ / μ + 0 τ 1 S ( τ , μ 1 ) e ( τ 1 τ ) / μ d τ μ , downward   at   bottom.
I ( 0 , μ ; τ 1 ) = t 0 U ( μ ) + r D ( μ 1 ) + t U ( μ 1 ) + ξ B , upward   at   top , I ( τ 1 , μ ; τ 1 ) = t 0 D ( μ ) + t D ( μ 1 ) + r U ( μ 1 ) + ξ B , downward   at   bottom ,
t 0 = e τ 1 / μ , t = 1 μ 1 k 1 μ k ( e k τ 1 e τ 1 / μ ) a 2 1 + μ 1 k 1 + μ k { e k τ 1 e [ ( 1 + 2 μ k ) / μ ] τ 1 } 1 a 2 e 2 k τ 1 , r = a 1 + μ 1 k 1 + μ k { 1 e [ ( 1 + μ k ) / μ ] τ 1 } a 1 μ 1 k 1 μ k { e 2 k τ 1 e [ ( 1 + μ k ) / μ ] τ 1 } 1 a 2 e 2 k τ 1 , ξ = 1 r t t 0 .
I ( 0 , μ , τ 1 < ∼ 0.1 ) = t 0 U ( μ ) + r D ( μ 1 ) + t U ( μ 1 ) + ξ B , upward   at   top, I ( τ 1 , μ , τ 1 < ∼ 0.1 ) = t 0 D ( μ ) + t D ( μ 1 ) + r U ( μ 1 ) + ξ B , downward   at   bottom, where t 0 = 1 τ 1 μ ; t = ϖ ( 1 + g ) / 2 μ τ 1 ; r = ϖ ( 1 g ) / 2 μ τ 1 ; ξ = 1 ϖ μ τ 1 = 1 r t t 0 .
      I ( τ , μ 1 ; τ 1 ) = B + r ( τ ; τ 1 ) [ D ( - μ 1 ) B ] + t ( τ ; τ 1 ) [ U ( μ 1 ) B ] , upward , I ( τ , μ 1 ; τ 1 ) = B + t ( τ ; τ 1 ) [ D ( - μ 1 ) B ] + r ( τ ; τ 1 ) [ U ( μ 1 ) B ] , downward ,
I ( 0 , μ 1 ; τ 1 < ∼ 0.1 ) = B + r [ D ( μ 1 ) B ] + t [ U ( μ 1 ) B ] = U ( μ 1 ) + r [ D ( μ 1 ) U ( μ 1 ) ] + ξ [ B U ( μ 1 ) ] , upward at top, I ( τ 1 , μ 1 ; τ 1 < ∼ 0.1 ) = B + t [ D ( μ 1 ) B ] + r [ U ( μ 1 ) B ] = D r [ D ( μ 1 ) U ( μ 1 ) ] + ξ [ B D ( μ 1 ) ] , downward at bottom, where t = 1 1 ϖ ( 1 + g ) / 2 μ 1 τ 1 ; r = ϖ ( 1 g ) / 2 μ 1 τ 1 ; ξ = 1 ϖ μ 1 τ 1 = 1 r t .
I ( 0 , μ ; τ 1 < ∼ 0.1 ) = B + r [ D ( μ 1 ) B ] + t [ U ( μ 1 ) B ] + t 0 [ U ( μ ) B ]       = U ( μ 1 ) + r [ D ( μ 1 ) U ( μ 1 ) ] + ξ [ B U ( μ 1 ) ] + t 0 [ U ( μ ) U ( μ 1 ) ] , upward at top, I ( τ 1 , μ ; τ 1 < ∼ 0.1 ) = B + r [ U ( μ 1 ) B ] + t [ D ( μ 1 ) B ] + t 0 [ D ( μ ) B ]           = D ( μ 1 ) r [ D ( μ 1 ) U ( μ 1 ) ] + ξ [ B D ( μ 1 ) ] + t 0 [ D ( μ ) D ( μ 1 ) ] , downward at bottom,   where t 0 = 1 τ 1 μ ; t = ϖ ( 1 + g ) / 2 μ τ 1 ; r = ϖ ( 1 g ) / 2 μ τ 1 ; ξ = 1 ϖ μ τ 1 = 1 r t t 0 .
M ( θ LOS ) = M atm + t atm ( I D & U + I L & R ) ,
I D & U = t 0 D ( μ D & U ) + t D ( μ 1 ) + r U ( μ 1 ) + ξ B = B + r [ U ( μ 1 ) B ] + t [ D ( μ 1 ) B ] + t 0 [ D ( μ D & U ) B ] , ( 22 a )   where t 0 = { 1 - τ Δz μ D & U , LOS through cloud's bottom          and top 0 , LOS through cloud's sides } , t = ϖ ( 1 + g ) / 2 μ D & U τ Δz ; r = ϖ ( 1 - g ) / 2 μ D & U τ Δz ; ξ = 1 - r - t - t 0 , μ D & U = cos ( θ LOS ) ,
I L & R = t 0 L ( μ L & R ) + t L ( μ 1 ) + r R ( μ 1 ) + ξ B = B + r [ R ( μ 1 ) B ] + t [ L ( μ 1 ) B ] + t 0 [ L ( μ L & R ) B ] , ( 22 b )   where t 0 = { 1 - τ Δx μ L & R , LOS through cloud's sides 0 , LOS through cloud's bottom          and top } , t = ϖ ( 1 + g ) / 2 μ L & R τ Δx ; r = ϖ ( 1 - g ) / 2 μ L & R τ Δx ; ξ = 1 - r - t - t 0 , μ L & R = cos ( π 2 - θ LOS ) .
M ( θ LOS , no   cloud ) = { M atm + t atm D ( μ D & U ) , looking   up:   LOS   through   cloud's   bottom   and   top , M atm + t atm L ( μ L & R ) , looking   up:   LOS   through   cloud's   sides , M atm + t atm U ( μ D & U ) , looking  down: LOS   through   cloud's   bottom   and   top, M atm + t atm L ( μ L & R ) , looking  down:  LOS   through   cloud's   sides } .
M ( θ LOS ; ϖ 0 ) = M ( θ LOS , no cloud ) + t atm { B + τ Δx μ L & R [ B - L ( μ L & R ) ] } , vapor cloud ; looking up , M ( θ LOS ; 0 < ϖ < 1 ) = M ( θ LOS , no cloud ) + t atm ( B + τ Δx μ L & R [ B - L ( μ L & R ) + ϖ { 1 + g 2 [ L ( - μ 1 ) - B ] + 1 - g 2 [ R ( μ 1 ) - B ] } ] , + τ Δz μ D & U ϖ { 1 + g 2 [ D ( - μ 1 ) - B ] + 1 - g 2 [ U ( μ 1 ) - B ] } ) , aerosol cloud; looking up, ( 24 )   where μ D & U = cos ( θ LOS ) and μ L & R = cos ( π 2 - θ LOS ) .
M ( θ LOS ; 0 < ϖ < 1 ) = M ( θ LOS , no   cloud ) + t atm × [ B + τ Δ x μ L & R ( B L ( μ L & R ) + ϖ 2 { L ( μ 1 ) + R ( μ 1 ) 2 B + g [ L ( μ 1 ) R ( μ 1 ) ] } ) + τ Δ z μ D & U × ϖ 2 { D ( μ 1 ) + U ( μ 1 ) 2 B + g [ D ( μ 1 ) U ( μ 1 ) ] } ] ( aerosol   cloud;  looking   up ) ,
Δ M thermal = τ Δ x μ L & R [ B L ( μ L & R ) ] , ( aerosol cloud: looking up ) , Δ M scatter = τ Δ x μ L & R ϖ { 1 + g 2 [ L ( μ 1 ) B ] + 1 g 2 [ R ( μ 1 ) B ] } + τ Δz μ D & U ϖ { 1 + g 2 [ D ( μ 1 ) B ] + 1 g 2 [ U ( μ 1 ) B ] } , (26)
where μ D & U = cos ( θ LOS ) and μ L & R = cos ( π 2 θ LOS ) .

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