Bloom or bust: plankton give clues to climate change

Remote ‘marine deserts’ and dense plankton blooms could provide scientists with clues for understanding climate change.
A research team will set sail from Southampton, Friday, 17th September 2004, for the start of an expedition to study the interaction between the atmosphere and plankton – tiny floating marine organisms. By monitoring these organisms and the influence of changing climate on their growth, they hope to discover whether they act as a source of carbon dioxide, or a ‘sink’ in which the carbon is contained.

Dr Andy Rees, Principal Scientist on the ship said ‘The ship will pass close to the coast of Africa, where we hope to find large numbers of plankton, called blooms. These blooms may be due to nutrient rich water rising to the surface or to dust, laden with nutrients, blown across from the Sahara providing food for the plankton. These areas act as natural chimneys of gases which contribute to global warming. We will have the opportunity to sample some hugely contrasting environments because of the meeting of waters from the northern and southern hemispheres. We will compare this area with barren desert regions of the Atlantic where there are very small numbers of plankton.’

Whilst the ship is at sea, the scientists will also be receiving satellite pictures showing the colour of the ocean from space, which will help them to locate the plankton blooms. Dr Barney Balch, a US scientist funded by NASA, will also be collecting data to improve interpretation of these satellite pictures in order to understand the distribution of certain types of plankton which have a significant impact on atmospheric chemistry.

The expedition, aboard the RRS Discovery, is part of the Atlantic Meridional Transect Programme (AMT), a £2.3 million project funded by the Natural Environment Research Council. This annual expedition from Southampton to Cape Town will provide a unique ten year data set which will aid scientists in their studies of long-term impacts of climate change.