The colour of the sea depends on its composition
and the way the components of seawater absorb and/or scatter light.
For example, the colour of the ocean is affected by sediments in
suspension (sand, mud, clay), phytoplankton, dissolved organic matter
from plant decomposition, etc. This research project is based on
but it moves in the opposite direction.
The objective is to develop methods to convert satellite measurements
into maps of chlorophyll (an indicator of phytoplankton) and suspended
Why look at the sea's colour ?
Nitrates and phosphates from human activity
(such as the agricultural use of fertilisers) reach the sea via
the rivers. These biological nutrients can significantly modify
the coastal ecosystem and cause a proliferation of undesirable species
of phytoplankton (microscopic marine plants). Scientists call this
phenomenon eutrophication. According to international
agreements such as the Oslo and Paris Conventions, now
OSPAR Convention, or the prevention of marine pollution, the
states responsible for eutrophication problems must take measures
to reduce such pollution, for example by limiting the use of fertilisers
and constructing waste water treatment plants. There is also an
international obligation to monitor the evolution of this problem.