Mini Lesson

Historic Ocean Chlorophyll Concentrations - Mapped Plot

Mini Lesson

  1. Analyze the Chlorophyll Concentrations in Surface Ocean Waters mapped image.
    Ocean Chlorophyll Concentrations
    The chlorophyll concentration data shown here were obtained from global satellite measurements by the SeaWiFS and MODIS-Aqua projects of the National Aeronautics and Space Administration (NASA). Credit: NASA, NOAA,
  2. Identify what living organisms may be observed using chlorophyll data.

    Recall  that phytoplankton are microscopic, floating, plant-like organisms that live in oceans, lakes, and rivers. They use photosynthetic pigments (like chlorophyll) to convert energy from the Sun into organic matter. For this reason, NASA satellites can observe the amount of phytoplankton present in the ocean by measuring chlorophyll concentrations.

  3. Review the color bar scale below.  What do the different colors mean as they are related to phytoplankton?
  4. After looking at this map, what are the different regions that you see? 
  5. Compare the Chlorophyll Concentrations in the coastal areas to the open ocean. What do you observe? 
  6. Compare lower latitudes like those in Florida or Hawaii versus higher latitudes like those in Alaska? 
  7. Compare the West Coast vs. East Coast concentrations. 

color bar
Credit: NASA, NOAA,

Note: NASA satellites measure large areas of the world's ocean and have the ability to make these observations frequently, which is useful for evaluating long-term changes. There is one limitation to be made aware of is the trade-off of being only able to measure chlorophyll concentrations near the ocean's surface.  This could potentially underestimate the total amount of phytoplankton found in all water depths. 

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