color of diatoms from space
How can you see diatoms from space if you can't even see them from the
beach? Some environments are so favorable for diatom accumulation that
extremely high concentrations of diatoms can change the color of the ocean's
surface waters. The brownish chloroplasts are the source of color. By
noting the color of the ocean, the ocean's productivity can be estimated;
the logic being - the more photosynthetic organisms there are, the more
tinted the ocean will appear from a distance. It is then a matter of knowing
how different tints correspond to particular abundances of organisms.
While they're of primary importance, diatoms are not the only photosynthetic
organisms in the ocean.
SeaWiFS is a research program that observes the ocean's
color from space using satellites. It is important to monitor the ocean's
color because this knowledge helps us to anticipate changes in the earth's
climate. Photosynthetic organisms such as diatoms play a key role in regulating
the earth's atmospheric carbon dioxide and thus the earth's climate. The
subject is quite complex. We'll explore this in a future module.
Click on the image above to take
a closer look!