BCC Geospatial Center of the CUNY CREST Institute
Sentinel-3
What's Sentinel-3?
Sentinel-3 is a two-satellite constellation (Sentinel-3A and Sentinel-3B) with multiple instruments. It's designed to give us a broad, overall view of our oceans and land. It has a special "color" camera, a thermometer, and a radar altimeter (like a very precise ruler).
What does it track?
Sea Temperature
How warm the oceans are, signs of warming
What does it measure?
It provides a wide range of measurements for both marine and terrestrial environments:
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Ocean: Sea surface temperature, sea level height (and how it's changing!), ocean color (which tells us about tiny plants in the water, like algae blooms), and wave height.
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Land: Land surface temperature, vegetation health (on a larger scale), and even fire detection.
What instruments does it use?
Sentinel-3 uses 4 instruments or sensors to give us land ocean data. These sensors are nothing but special tools:
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SLSTR (Sea and Land Surface Temperature Radiometer)
Like a space thermometer, it checks how hot or cold the surface of the Earth is — whether it’s land, sea, or ice. This helps us track climate change, heatwaves, or melting glaciers.
OLCI (Ocean and Land Color Instrument)
Like a digital color detector, it spots changes in ocean color caused by algae blooms, sediments, or pollution. The greener the water, the more phytoplankton (tiny plant-like organisms), this is key for marine life and carbon balance.
SRAL (Synthetic Aperture Radar Altimeter)
Imagine bouncing a radar signal from space to the ocean and back — like a space ruler. It tells us how high the sea level is at different places. This helps scientists monitor rising seas, tsunamis, and even the shape of ocean currents.
MWR (Microwave Radiometer)
This works like a moisture sensor in space. It detects humidity, cloud water, and rain potential — helping forecast weather and understand storm patterns.
What we Get (Data Products)
Sentinel-3's diverse instruments lead to many different data products:
OLCI Products
Provide information on ocean color parameters like chlorophyll-a concentration (a measure of marine plant life), total suspended matter (like sediment in water), and water transparency. Over land, they contribute to large-scale vegetation health maps.
SLSTR Products
Deliver very accurate sea surface temperature (SST) and land surface temperature (LST) maps. They can also detect active fires and provide information about clouds.
SRAL Altimetry Products
Deliver very accurate sea surface temperature (SST) and land surface temperature (LST) maps. They can also detect active fires and provide information about clouds.