Methods of assessing uncertainty in determining particle size distribution parameters from optical backscatter and extinction measurements

Ben R. Herman; Barry Gross; Fred Moshary; Samir Ahmed

doi:10.1117/12.509348

23 December 2003 Methods of assessing uncertainty in determining particle size distribution parameters from optical backscatter and extinction measurements

Ben R. Herman, Barry Gross, Fred Moshary, Samir Ahmed

Author Affiliations +

Proceedings Volume 5154, Lidar Remote Sensing for Environmental Monitoring IV; (2003) https://doi.org/10.1117/12.509348
Event: Optical Science and Technology, SPIE's 48th Annual Meeting, 2003, San Diego, California, United States

Abstract

The use of multi-wavelength lidar measurements can in principle be used to estimate aerosol extinction and backscatter profiles. From the resultant multi-wavelength profiles, an estimate of particle size distribution parameters can be inferred. However, the confidence of the retrieval depends on the accuracy of the retrieved backscatter and extinction coefficients. Conventional approaches determine errors by performing statistical calculations on the results of inversions of simulated measurements with errors derived from a random number generator. There is a certain ambiguity about the validity of this method which we try to resolve. We introduce two alternative methods. One is a reverse Monte-Carlo method which gives an ensemble of distribution parameters that produce simulated measurements whose inversions match the inversion of the retrieved measurements. Substantial differences in the results of the aforementioned methods were found. In order to clarify these differences, a semi-analytic approach is introduced that formulates the conditional probability density function of underlying particle size distribution parameters given a set of measurements (from the combined probability function with the underlying optical data). Results using the probability density function were found to be closer to the statistics of the reverse Monte-Carlo method than the conventional method.

Citation Download Citation

Ben R. Herman, Barry Gross, Fred Moshary, and Samir Ahmed "Methods of assessing uncertainty in determining particle size distribution parameters from optical backscatter and extinction measurements", Proc. SPIE 5154, Lidar Remote Sensing for Environmental Monitoring IV, (23 December 2003); https://doi.org/10.1117/12.509348

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available