A Noctiluca scintillans bloom in the north Arabian Sea on 2 March 2017

Ocean colour services


 A Noctiluca scintillans bloom in the north Arabian Sea on 2 March 2017
 A Noctiluca scintillans bloom in the north Arabian Sea on 2 March 2017

Ocean colour data provides a window into the ocean living ecosystems, as well as measurements of water quality and sediment dynamics.

Last Updated

31 May 2022

Published on

27 July 2018

OLCI provides spectral information on the colour of the oceans. This data can be used to monitor global ocean primary production by phytoplankton, the basis of nearly all life in our seas.

Ocean colour data is also vital to understand climate change — ocean colour is one of the Essential Climate Variables listed by the World Meteorological Organization to detect biological activity in the ocean’s surface layer. Phytoplankton take up carbon dioxide (CO2) during photosynthesis, making them important carbon sinks. Ocean colour data can be used to monitor the annual global uptake of CO2 by phytoplankton on a global scale. Using this data we can study the wider Earth system, for instance the El Niño/La Niña phenomena and how these impacts the ocean ecosystem.

Beyond climate, ocean colour data is also useful to look at more sporadic events. OLCI data can be used track sediment transport, monitor coastal water quality and track and forecast harmful algal blooms that are a danger to humans, marine/freshwater life and aquaculture.

The global picture of ocean ecosystems provided by ocean colour data can guide sustainable marine resource management and support reporting obligations of the European Union's legislation within Marine Strategy Framework Directive and Water Framework Directive, the goal of which is to achieve or maintain Good Environmental Status of the seas by the year 2020.

Phytoplankton Blooms spotted by Sentinel-3
Figure 1: Coccolithophores in the Barents Sea, using Sentinel-3A OLCI Level 1 data from 30 July 2018.

The products are available in:

  • Near-Real-Time (NRT): products shall be available to the users within three hours after sensing.
  • Non-Time-Critical (NTC): products available to the users within one month after sensing.

Level 1 data provides ocean colour products derived from the top of atmosphere signal. Level 2 products include the atmospherically corrected water leaving signal, as well as derived products including chlorophyll and total suspended matter estimates.


OLCI product releases

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