Atmospheric carbon dioxide is the most import human-made greenhouse gas responsible for global warming. Credit: ESA/CCI Ocean Colour/Climate Monitoring User Group/Planetary Visions

Oceans assist in removing carbon dioxide from the atmosphere: phytoplankton accumulates carbon dioxide through photosynthesis and their chlorophyll colors the ocean’s waters. Satellites use this color to measure chlorophyll, which helps scientists to calculate how much carbon dioxide is absorbed or emitted.