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 and threshold orange

Id Variable Layer App Area Uncertainty Stability / decade Hor Res Ver Res Obs Cyc Timeliness Coverage Conf Level Val Date Source
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
Climate Monitoring (GCOS) 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)