Classification of Polar Stratospheric Clouds Using LIDAR Measurements From the SAGE III Ozone Loss and Validation Experiment

Abstract

Backscatter LIDAR measurements from the stratospheric aerosol and gas experiment (SAGE) III ozone loss and validation experiment (SOLVE) have been used to identify classes of polar stratospheric clouds (PSCs) and their corresponding characteristics. Volume backscatter at 532 nm (Beta532) and 1064 nm (Beta1064), scattering ratio at 532 nm (R532) and 1064 nm (R1064), aerosol depolarization (delta(a)), and color ratio (Beta532/Beta1064), and temperature (T) were used to categorize PSCs via principal component analysis (PCA) and Cluster Analysis (CA). The clusters found in this study are consistent with previous studies of PSCs of types Ia (R532 < 1.5 and delta(a) > 0.1), Ia-enhanced (R532 > 1.4 and delta(a) > 0.1), Ib (R532 > 2 and delta(a) < 0.025), and II (532 > 7 and delta(a) > 0.1). In addition, a cluster predominantly found on the outside edges of clouds, which does not fit the definition of these PSCs, which has low R532 and delta(a) values, was found. The clustering analysis of PSC data provides an objective and automated method for the production of image plots that show a two-dimensional distribution of the PSC particle types. Such capabilities will be useful for analyzing large data sets such as will be produced by space-borne LIDARS (laser identification and ranging system).

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Document Details

Document Type
Technical Report
Publication Date
Jun 01, 2007
Accession Number
ADA469817

Entities

People

  • Ali H. Omar
  • Chris A. Hostetler
  • Melvin A. Felton Jr.
  • Thomas A. Kovacs

Organizations

  • United States Army Research Laboratory

Tags

Communities of Interest

  • Space

DTIC Thesaurus Topics

  • Algorithms
  • Atmospheric Sciences
  • Backscattering
  • Chemical Reactions
  • Classification
  • Clustering
  • Data Sets
  • Depolarization
  • Factor Analysis
  • Information Science
  • Measurement
  • Particles
  • Physical Properties
  • Range Finding
  • Scattering
  • Two Dimensional
  • Validation

Fields of Study

  • Physics

Readers

  • Aerosol Science/Aerosol Physics
  • Solar Photovoltaics and Thermoelectric Devices.
  • Systems Analysis and Design

Technology Areas

  • Directed Energy
  • Directed Energy - Pulsed-Laser Deposition
  • Space