### Abstract

A new algorithm to estimate lidar ratios of aerosol layers with a monochromatic Mie-scattering lidar profile is proposed. The algorithm employs both the forward and the backward solutions of the monochromatic single-scattering lidar equation. The lidar ratios are estimated through an iterative procedure to match the two solutions by correcting a lidar ratio assigned at the beginning of the procedure. The algorithm has been applied to simulated lidar profiles and a measured one from the literature. In testing of the simulated profiles, the estimation errors of the lidar ratios were investigated for four boundary conditions - clear to turbid conditions - by scanning boundary values and extinction coefficients of an aerosol layer. This investigation indicated that the algorithm estimates the lidar ratio with sufficient accuracy under clear boundary conditions even with inaccurate boundary values, but requires correct boundary values under turbid boundary conditions. The algorithm was successfully applied to the measured lidar profile of a thin aerosol layer. The obtained lidar ratio was reasonably plausible. This suggests that an enhanced form of this algorithm using the forward and the backward solutions would be able to determine the lidar ratios and boundary values from only a lidar profile measured under arbitrary atmospheric conditions.

Original language | English |
---|---|

Pages (from-to) | 6513-6519 |

Number of pages | 7 |

Journal | Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers |

Volume | 43 |

Issue number | 9 A |

DOIs | |

Publication status | Published - Sep 2004 |

### Fingerprint

### Keywords

- Extinction-to-backscatter ratio
- Inversion
- Lidar ratio
- Mie scattering

### ASJC Scopus subject areas

- Physics and Astronomy (miscellaneous)

### Cite this

*Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers*,

*43*(9 A), 6513-6519. https://doi.org/10.1143/JJAP.43.6513

**A bidirectional iteration algorithm for determining lidar ratios and its use to evaluate boundary values in the lidar inversion.** / Iokibe, Kengo; Itoh, Yoshinori; Toyota, Yoshitaka; Wada, Osami; Koga, Ryuji.

Research output: Contribution to journal › Article

*Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers*, vol. 43, no. 9 A, pp. 6513-6519. https://doi.org/10.1143/JJAP.43.6513

}

TY - JOUR

T1 - A bidirectional iteration algorithm for determining lidar ratios and its use to evaluate boundary values in the lidar inversion

AU - Iokibe, Kengo

AU - Itoh, Yoshinori

AU - Toyota, Yoshitaka

AU - Wada, Osami

AU - Koga, Ryuji

PY - 2004/9

Y1 - 2004/9

N2 - A new algorithm to estimate lidar ratios of aerosol layers with a monochromatic Mie-scattering lidar profile is proposed. The algorithm employs both the forward and the backward solutions of the monochromatic single-scattering lidar equation. The lidar ratios are estimated through an iterative procedure to match the two solutions by correcting a lidar ratio assigned at the beginning of the procedure. The algorithm has been applied to simulated lidar profiles and a measured one from the literature. In testing of the simulated profiles, the estimation errors of the lidar ratios were investigated for four boundary conditions - clear to turbid conditions - by scanning boundary values and extinction coefficients of an aerosol layer. This investigation indicated that the algorithm estimates the lidar ratio with sufficient accuracy under clear boundary conditions even with inaccurate boundary values, but requires correct boundary values under turbid boundary conditions. The algorithm was successfully applied to the measured lidar profile of a thin aerosol layer. The obtained lidar ratio was reasonably plausible. This suggests that an enhanced form of this algorithm using the forward and the backward solutions would be able to determine the lidar ratios and boundary values from only a lidar profile measured under arbitrary atmospheric conditions.

AB - A new algorithm to estimate lidar ratios of aerosol layers with a monochromatic Mie-scattering lidar profile is proposed. The algorithm employs both the forward and the backward solutions of the monochromatic single-scattering lidar equation. The lidar ratios are estimated through an iterative procedure to match the two solutions by correcting a lidar ratio assigned at the beginning of the procedure. The algorithm has been applied to simulated lidar profiles and a measured one from the literature. In testing of the simulated profiles, the estimation errors of the lidar ratios were investigated for four boundary conditions - clear to turbid conditions - by scanning boundary values and extinction coefficients of an aerosol layer. This investigation indicated that the algorithm estimates the lidar ratio with sufficient accuracy under clear boundary conditions even with inaccurate boundary values, but requires correct boundary values under turbid boundary conditions. The algorithm was successfully applied to the measured lidar profile of a thin aerosol layer. The obtained lidar ratio was reasonably plausible. This suggests that an enhanced form of this algorithm using the forward and the backward solutions would be able to determine the lidar ratios and boundary values from only a lidar profile measured under arbitrary atmospheric conditions.

KW - Extinction-to-backscatter ratio

KW - Inversion

KW - Lidar ratio

KW - Mie scattering

UR - http://www.scopus.com/inward/record.url?scp=9144243919&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=9144243919&partnerID=8YFLogxK

U2 - 10.1143/JJAP.43.6513

DO - 10.1143/JJAP.43.6513

M3 - Article

AN - SCOPUS:9144243919

VL - 43

SP - 6513

EP - 6519

JO - Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes

JF - Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes

SN - 0021-4922

IS - 9 A

ER -