Ocean Colour..

... means different things to different people. For some it's simply the ever-changing colour of the sea; for oceanographers it means studying the ocean from satellites that measure visible light.   We have divided the subject into four:

1. Light and colour in the ocean: what light is, how colours occur, and what they tell us about the water. To understand you must know about electromagnetic waves (a topic in 'E-quations').

2. Plant life in the ocean: how ocean colour is used to study tiny marine plants; it's all to do with photosynthesis.

3. Why measure ocean colour? There are many reasons, here is just one: the role of marine plants in the global carbon cycle.

4. Ocean colour from space: how measurments made from satellites orbiting the Earth are turned into useful information.

Finally, we have included some things to try as well as quizzes and puzzles linked to the ocean colour theme.