At 500,000 locations across the globe, scientists from numerousuniversities joined forces to make a survey of whenand where which plankton species occur, and to determine how much carbon they absorb. And they have brought this data together in a global atlas names MEREDAT, which provides information on organisms ranging from phytoplankton and bacteria of just one picometre (one billionth of a metre) in size to centimetre-large zooplankton such as krill and other small crustaceans.