Name: _________________________________       Date: _____________

The world's oceans are teeming with both animal-like and plant-like plankton, or phytoplankton. These microscopic plants are the base of ocean food chains. In this activity, you'll learn more about their important role in ocean ecosystems. You'll also see the impact of sea-surface temperature and pollution on plankton levels.

  1. Begin with this Planet Diary report Chlorophyll Increases Along Coasts. What's the link between chlorophyll level and phytoplankton?
  2. What causes nutrient stress?
  3. Why are large plankton blooms unhealthy?
  4. Why are phytoplankton levels dropping in the mid-ocean?
  5. How is sea-surface temperature linked to plankton levels?
  6. View NASA's global chlorophyll map. Use the slider to explore how the chlorophyll (and phytoplankton) levels change seasonally and year to year. Read the caption below the map. What stimulates phytoplankton growth?
  7. Why are chlorophyll concentrations usually higher in cold polar regions?
  8. Read What Are Phytoplankton? Scroll to The Life and Death of Phytoplankton. What happens to an ecosystem when phytoplankton starve?