By absorbing half of the carbon dioxide emitted into the atmosphere, the oceans have a profound influence on climate. However, their ability to take up this carbon dioxide might be impaired as a result of climate change. To determine their response to global warming, ESA has backed two projects that provide systematic data on key oceanic variables - colour and temperature.
The Medspiration project, aimed at charting sea-surface temperatures, and the GlobCOLOUR project, aimed at developing a data set of global ocean colour, both combine data measured independently by several different satellite systems into a set of products that represent the best possible measurements and allow researchers from various fields to pool their efforts in an attempt to understand how the climate is reacting to changes.
"Clues to climatic changes may already be written on the oceans' surface. Because we now have detailed data that allow us to look for correlations, we are learning how to read those messages," said Prof. Ian Robinson at the National Oceanography Centre, Southampton (NOCS) and Medspiration Project Manager. "ESA is making a difference to public awareness of climate change by helping us to better understand the sea surface temperature story."
Phytoplankton, microscopic marine plants that drift on or near the surface of the sea, absorb atmospheric carbon dioxide through photosynthesis and convert it into organic carbon. This process is known as primary production. While individually microscopic, phytoplankton chlorophyll collectively tints the surrounding ocean waters, providing a means of detecting these tiny organisms from space with dedicated ocean colour sensors.
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