BackForwardInstrument:  OCI (FORMOSAT) 

Instrument details
Acronym OCI (FORMOSAT)
Full name Ocean Color Imager
Purpose Monitoring of ocean water quality and health
Short description 7-channel VIS/NIR spectro-radiometer [see details below]. One channel, 555 nm, is actually redundant.
Background New development
Scanning Technique Pushbroom, 896 pixels/line, 700 km swath
Resolution 800 m at s.s.p.
Coverage / Cycle Daily over a limited latitude range due to the low-inclination satellite orbit (35°)
Mass 15.2 kg Power 33 W Data Rate 655.5 kbps

 

Providing Agency NSPO
Instrument Maturity Flown on an R&D satellite
Utilization Period: 1999 to 2004
Last update: 2017-08-01
Detailed characteristics

Central wavelength

Bandwidth

SNR at expected input radiance

444 nm

20 nm

450

490 nm

20 nm

450

512 nm

20 nm

450

555 nm

20 nm

450

555 nm

20 nm

350

670 nm

20 nm

350

869 nm

40 nm

350

Satellites this instrument is flying on

Note: a red tag indicates satellites no longer operational, a green tag indicates operational satellites, a blue tag indicates future satellites

Instrument classification
  • Earth observation instrument
  • Passive optical radiometer or spectrometer
  • Moderate resolution optical imager
WIGOS Subcomponents
  • Subcomponent 1
  • Narrow-band or hyperspectral imagers
  • Narrow-band imager (for ocean colour)
Mission objectives
Primary mission objectives
  • Colour Dissolved Organic Matter (CDOM)
  • Ocean Diffuse Attenuation Coefficient (DAC)
  • Ocean chlorophyll concentration
  • Ocean suspended sediments concentration
  • Oil spill cover
Evaluation of Measurements

The following list indicates which measurements can typically be retrieved from this category of instrument. To see a full Gap Analysis by Variable, click on the respective variable.

Note: table can be sorted by clicking on the column headers
Note: * Primary mission objective.
VariableRelevance for measuring this variableOperational limitationsExplanation
Aerosol column burden5 - marginalCloud sensitive.. Daylight only.VIS (with narrow bandwidth) and NIR channels
Aerosol effective radius5 - marginalCloud sensitive.. Daylight only.VIS (with narrow bandwidth) and NIR channels
Aerosol mass mixing ratio5 - marginalCloud sensitive.. Daylight only.VIS (with narrow bandwidth) and NIR channels
Aerosol Optical Depth5 - marginalCloud sensitive.. Daylight only.VIS (with narrow bandwidth) and NIR channels
Aerosol type5 - marginalCloud sensitive.. Daylight only.VIS (with narrow bandwidth) and NIR channels
Biomass5 - marginalCloud sensitive.. Index only.. Daylight only.VIS and NIR channels. Biomass inferred from NDVI
Cloud cover5 - marginalDaylight only.VIS and NIR channels
Cloud optical depth4 - fairLow-density cloud only.. Daylight only.VIS and NIR channels
Cloud type5 - marginalDaylight only.VIS and NIR channels
Colour Dissolved Organic Matter (CDOM)*4 - fairCloud sensitive.. Daylight only.Many narrow-bandwith VIS channels, suitable for more water types, in open ocean
Downward short-wave irradiance at Earth surface5 - marginalCloud sensitive.. Highly indirect.VIS and NIR channels
Earth surface albedo5 - marginalCloud sensitive.VIS channels
Fire fractional cover5 - marginalCloud sensitive.. Coarse spatial resolution.. Daylight only.VIS channels
Fraction of Absorbed PAR (FAPAR)3 - highCloud sensitive.VIS channels including Red at 700 nm
Leaf Area Index (LAI)4 - fairCloud sensitive.. Daylight only.VIS and NIR channels. LAI inferred from NDVI
Normalised Difference Vegetation Index (NDVI)3 - highCloud sensitive.VIS and NIR channels
Ocean chlorophyll concentration *4 - fairCloud sensitive.. Daylight only.Many narrow-bandwith VIS channels, suitable for more water types, in open ocean
Ocean Diffuse Attenuation Coefficient (DAC)*4 - fairCloud sensitive.. Daylight only.Many narrow-bandwith VIS channels, suitable for more water types, in open ocean
Ocean suspended sediments concentration*4 - fairCloud sensitive.. Daylight only.Many narrow-bandwith VIS channels, suitable for more water types, in open ocean
Oil spill cover*5 - marginalCloud sensitive.. Daylight only.VIS channels with narrow bandwidth
Photosynthetically Active Radiation (PAR)3 - highCloud sensitive.VIS channels, range accurately sampled
Short-wave cloud reflectance5 - marginalNo specific limitation.VIS and NIR channels
Snow cover4 - fairCloud sensitive.. Daylight only.VIS and NIR channels
Soil moisture at surface5 - marginalCloud sensitive.. Index only.. Daylight only.VIS and NIR channels. Soil moisture inferred from differential brightness
Upward short-wave irradiance at TOA5 - marginalSpectral interpolation needed.. Information on BRDF needed.VIS and NIR channels
Aerosol volcanic ash5 - marginalCloud sensitive.. Daylight only.VIS and NIR channels
Aerosol volcanic ash Total Column5 - marginalCloud sensitive.. Daylight only.VIS and NIR channels