Question: Wouldn't sallow seas, coral reef and dumping areas effect your work; those do change the colour of the ocean from space?

Hayley Evers-King answered on 10 Mar 2013:

You’re absolutely right! This is one of the most difficult things about my work. The color of the ocean isn’t caused by just one thing. As you’ve said there are lots of things in water that can change the color – phytoplankton (tiny plant-like organisms), mud from rivers, oil (and other things dumped in the water), coral reefs and in shallow waters, the bottom also changes the colour.

To solve this problem, we use instruments called radiometers. Your eyes see the colours of the spectrum (the ones you see split up in a rainbow) mixed together in different proportions to tell you the overall color of something (e.g. if something reflects some green and some blue light for example, it will look turquoise to you). But with radiometers we can measure how much of the different colors of light are reflected by measuring at different wavelengths. We can use this information to tell us about the different things in the ocean.

This means that our ocean colour data from space can be used for lots of different purposes – we can identify ice, different habitats (sea grasses/coral reefs), oil spills and many other things.