Sentinel-3

Satellite Description

The Sentinel-3 mission is a constellation of two imaging satellites operated by ESA with the support of EUMETSAT. Sentinel-3A was launched in 2016, followed by Sentinel-3B in 2018. Each satellite has 3 instruments on board with different science goals. The Ocean and Land Colour Imager (OLCI) observes in 21 spectral bands, the Sea and Land Surface Temperature Radiometer (SLSTR) observes in 11 spectral bands and the SAR (Synthetic Aperture Radar) Radar Altimeter (SRAL) primarily monitors sea surface topography, aided by a secondary Microwave Radiometer (MWR) instrument which collects atmospheric water data for correction application. Sentinel-3 provides robust global data products at high frequency that can support ocean forecasting and environmental and climate monitoring. The optical payload consists of the OLCI and SLSTR instruments together which build upon the previous capabilities of MERIS and AATSR onboard the Envisat satellite with new spectral channels and sun-glint avoidance. The topography payload consists of the SRAL instrument which improves upon the Envisat altimeter by increasing the observing capabilities in coastal zones, inland waterways and for sea ice.

Observation Scenario

• Swath width: 1270 km (OLCI), 1420 km (SLSTR nadir), 750 km (SLSTR backwards)

• Orbit: Sun-synchronous

• Inclination: 98.65°

• Altitude: 807 km

• Lifetime: 7.5 years with fuel for additional 5 years

Sensor Characteristics

• OLCI: 21 spectral bands – VNIR to SWIR

• SLSTR: 11 spectral bands – VNIR, SWIR, MWIR, TIR

• SRAL: C and Ku-bands

• MWR: K and Ka-bands

Spatial Resolution

• OLCI: 300 m

• SLSTR: 500 m, 1 km (band dependent)

• SRAL: 300 m

Temporal Resolution

1 – 4 days (2 satellites) but varies with latitude.

Data Products

Both level-1 and level-2 products exist for all instruments. See  Sentinel-3 for further information and links to products for each instrument.

Archive Availability

Data is freely available:

• • Period: 2016 – present
• • Latency: Near Real-Time (3 hours), Short Time Critical (1 day), Non Time Critical (1 month)
• • Sources:
  •  • Copernicus Dataspace Ecosystem
  •  • Sentinel Hub
  •  • Google Earth Engine (OLCI only)
  •  • Planetary Computer (L2A only)

Data Continuity

S3A is expected to operate until 2026 and S3B until 2028. S3C and S3D are to provide continuity with launches expected in 2026 and 2028 respectively. For further information on Sentinel-3 see here.