kein folientitel - iap kühlungsborn.ppt

LIDAR: Introduction to selected topics LIDAR: What’s it all about? LIDAR = light detection and ranging (similar to radar, sodar) light: pulsed laser (nanosecond-range) scatterer: air molecules and aerosols detector: telescope and photon detectors ranging: time-resolved detection distinction between scatterersby optical properties (e.g. wavelengthand scattering cross section) LIDAR: What’s the use of it? vertical distribution of scatterers aerosol particles from troposphere to mesosphere existence, phase, optical thickness (extinction) particle size, particle number ??? trace gases in troposphere/stratosphere/mesosphere/ thermosphere concentration of pollutants: NO2, SO2, ..., H2O, O3, OH, metal atoms (Fe, Na, K, Ca, ...), Ca+ temperature of the troposphere/stratosphere/mesosphere/... 1. Introduction and Overview 2. Lidar Basics 3. Lidar Application: Aerosols 4. Lidar Application: Temperature Light Interaction with the Atmosphere Rayleigh scattering elastic; atoms or molecules Light Interactions with the Atmosphere (II) Light Interactions with the Atmosphere (III) Rayleigh-Raman spectrum Elastic Lidar Backscatter Signal Basic Lidar Equation Lidar System: Schematic Drawing 1. Introduction and Overview 2. Lidar Basics 3. Lidar Application: Aerosols 3.1 Aerosol Determination by “Slope Method” 3.2 Aerosol Determination by “Klett Method” 3.3 Aerosol Determination by “Ansmann Method” 4. Lidar Application: Temperature Aerosol in the Atmosphere 3.1 Aerosol Determination by “Slope Method” (I) 3.1 Aerosol Determination by “Slope Method” (II) Application of the “Slope Method” NLC photos 3.2 Aerosol Determination by “Klett Method” (I) 3.2 Aerosol Determination by “Klett Method” (II) Application of the “Klett Method”: Polar Stratospheric Clouds Polar Stratospheric Clouds 3.3 Aerosol Determination by “Ansmann Method” (I) 3.3 Aerosol Determination by “Ansmann Method” (II) Application of the “Ansmann Method”: Tropospheric Aerosol Methods for Aerosol Determination: A Compa