BackForwardInstrument:  OCM (OceanSat-3) 

Instrument details
Acronym OCM (OceanSat-3)
Full name Ocean Color Monitor
Purpose Ocean colour and aerosol
Short description 13 narrow-bandwidth VIS/NIR channels [see detailed characteristics below]
Background Evolution of the OCM flown on OceanSat 1 and 2
Scanning Technique Pushbroom, 6000 pixel/line (3700 useful), swath 1440 km
Resolution 360 m or 1080 m s.s.p. (see table)
Coverage / Cycle Global coverage in 2 days, in daylight
Mass 74 kg Power 85 W Data Rate 17 Mbps

 

Providing Agency ISRO
Instrument Maturity Flown on operational programme
Utilization Period: 2023 to 2030
Last update: 2021-11-04
Detailed characteristics

Central

wavelength

Bandwidth

SNR @ specified input

spectral radiance

IFOV

412 nm

10 nm

>1000 @ 91 W m-2 sr-1 μm-1

360 m

443 nm

10 nm

>1000 @ 84 W m-2 sr-1 μm-1

360 m

490 nm

10 nm

>1000 @ 66 W m-2 sr-1 μm-1

360 m

510 nm

10 nm

>1000 @ 56 W m-2 sr-1 μm-1

360 m

555 nm

10 nm

>1000 @ 46 W m-2 sr-1 μm-1

360 m

566 nm

10 nm

>1000 @ 43 W m-2 sr-1 μm-1

360 m

620 nm

10 nm

>1000 @ 31 W m-2 sr-1 μm-1

360 m

670 nm

10 nm

>1000 @ 25 W m-2 sr-1 μm-1

360 m

681 nm

7.5 nm

>1000 @ 23 W m-2 sr-1 μm-1

360 m

710 nm

10 nm

>1000 @ 20 W m-2 sr-1 μm-1

360 m

780 nm

10 nm

>800 @ 16 W m-2 sr-1 μm-1

1080 m

870 nm

20 nm

>800 @ 11 W m-2 sr-1 μm-1

1080 m

1010 nm

20 nm

>800 @ 5 W m-2 sr-1 μm-1

1080 m

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 burden3 - highCloud sensitive.. Daylight only.VIS (with narrow bandwidth) and NIR channels including 760 nm for high-level aerosol
Aerosol effective radius3 - highCloud sensitive.. Daylight only.VIS (with narrow bandwidth) and NIR channels including 760 nm for high-level aerosol
Aerosol mass mixing ratio3 - highCloud sensitive.. Daylight only.VIS (with narrow bandwidth) and NIR channels including 760 nm for high-level aerosol
Aerosol Optical Depth3 - highCloud sensitive.. Daylight only.VIS (with narrow bandwidth) and NIR channels including 760 nm for high-level aerosol
Aerosol type3 - highCloud sensitive.. Daylight only.VIS (with narrow bandwidth) and NIR channels including 760 nm for high-level aerosol
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 top height5 - marginalDaylight only.NIR channels to estimate the total-column O2 above the cloud top as measured around 760 nm
Cloud type5 - marginalDaylight only.VIS and NIR channels
Colour Dissolved Organic Matter (CDOM)*1 - primaryCloud sensitive.. Daylight only.Many narrow-bandwidth VIS channels, suitable for more water types, in open ocean and coastal zone
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 *1 - primaryCloud sensitive.. Daylight only.Many narrow-bandwidth VIS channels, suitable for more water types, in open ocean and coastal zone
Ocean Diffuse Attenuation Coefficient (DAC)*1 - primaryCloud sensitive.. Daylight only.Many narrow-bandwidth VIS channels, suitable for more water types, in open ocean and coastal zone
Ocean suspended sediments concentration*1 - primaryCloud sensitive.. Daylight only.Many narrow-bandwidth VIS channels, suitable for more water types, in open ocean and coastal zone
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 ash3 - highCloud sensitive.. Daylight only.VIS and NIR channels including 760 nm for high-level ashes
Aerosol volcanic ash Total Column3 - highCloud sensitive.. Daylight only.VIS and NIR channels including 760 nm for high-level ashes
Sea-ice cover5 - marginalCloud sensitive.. Daylight only.VIS and NIR (for contour enhancement) channels