BackForward Variable: Aerosol Optical Depth

Definition
Full name Aerosol Optical Depth
Definition The AOD is the effective depth of the aerosol column from the viewpoint of radiation propagation: Vertical column integral of spectral aerosol extinction coefficient AOD = exp(-K. Δz) where K is the extinction coefficient [km-1 ] and Δz the vertical path [km]
Measuring Units Dimensionless Uncertainty Units Dimensionless
Horizontal Res Units km Vertical Res Units
Stability Units Dimensionless (Stability /decade)

 

Comment: The AOD depends on wavelength. The GAW guidelines recommend AOD be measured at 3 or more wavelengths among 368, 412, 500, 675, 778, and 862 nm with a bandwidth of 5nm. Aerosol scattering optical depth and aerosol absorption optical depth are calculated in a corresponding fashion.
Last modified: 2011-08-08
Applied in OSCAR/Space Gap Analysis: Yes
Classification
  • Domain: Atmosphere
    • Sub-domain: Aerosols and radiation
      • Variable: Aerosol Optical Depth
        • Measured in Layers:
          • TC
          • TrC
          • MUS
          • UTLS
          • FT
          • PBL
          • M
  • Cross-cutting themes:

Requirements defined for Aerosol Optical Depth  (3)

This tables shows all related requirements. For more operations/filtering, please consult the full list of Requirements
Note: In reading the values, goal is marked blue, breakthrough green, threshold orange
Application-dependent Technical Priority (ATP) Magenta and Relative priority of the attributes Red

Id Variable Layer App Area ATP Uncertainty Layer/s Quality Coverage Quality Stability / decade Hor Res Ver Res Obs Cyc Timeliness Coverage Conf Level Val Date Source General Comment Application Area Comment Horizontal Coverage Comment Observation Comment Performance Comment
63 Aerosol Optical Depth MUS
UTLS
FT
PBL
M 		Climate-AOPC (deprecated) 0.01 Dimensionless
0.015 Dimensionless
0.02 Dimensionless 		1 km
2 km
10 km 		24 h
2 d
7 d 		7 d
14 d
60 d 		Global reasonable 2007-07-19 AOPC
66 Aerosol Optical Depth PBL Climate-AOPC (deprecated) 0.01 Dimensionless
0.015 Dimensionless
0.02 Dimensionless 		1 km
2 km
10 km 		24 h
2 d
7 d 		7 d
14 d
60 d 		Global reasonable 2007-07-19 AOPC
807 Aerosol Optical Depth FT
PBL 		2.5 Atmospheric Climate Monitoring 0.03 Dimensionless 0.02 Dimensionless 5 km
10 km 		4 h Global reasonable 2019-09-26 GCOS-200: The Global Observing System for Climate: Implementation Needs (Published 2016) Requirement for uncertainty in the GCOS IP is expressed as max (0.03; 10%)