Figure 10.24

Phytoplankton. (A) Phytoplankton include bacteria and algae. All phytoplankton are microscopic; hence, these drawings do not represent the actual size of each organism. Scale bars are provided to give the approximate relative sizes of each. (B) This phytoplankton bloom, shown as light-blue water, is in the Barents Sea, off the northern coast of Norway. In a phytoplankton bloom, phytoplankton populations increase dramatically. An individual phytoplanktonic organism lives only a few days, but blooms last several weeks.

(A. Sally Bensusen, NASA EOS Project Science Office; B. NASA image courtesy Jeff Schmaltz, MODIS Rapid Response Team at NASA GSFC)