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Images: The Rain of Ocean Particles and Earth's Carbon Cycle

Integration of sediment trap based measurements from a variety of locations allows investigators to estimate the global flux of carbon to the oceanA?s interior. (Jack Cook)

Conditions that influence removal of carbon-dioxide carbon from atmosphere to deep ocean are illustrated here and discussed in the article. (Jack Cook (thanks to Dan McCorkle))

Fecal pellets are about the size of a comma (,).

Transmision electron microscope image (enlarged some 3,000 times) of a section of a fecal pellet collected by a sediment trap in the North Atlantic. It includes undigested, phytoplankton cell organelles, including chloroplasts. The blue (artificially colored) areas represent remains of coccoliths that were eaten by a zoolankter and passed unaffected through the gut. Coccoliths are composed of nearly pure calcite, the heaviest mineral produced by marine organisms, which makes a fecal pellet heavy enough to settle rapidly through the water column. (Susumu Honjo)

Organic carbon flux measured over at least one year with time-series sediment traps in the Northern Hemisphere in grams per square meter per year. This figure integrates data derived from sediment traps around the world, including WHOI PARFLUX results. Note the huge export flux in the Arabian Sea and relatively large annual flux in the northwestern Pacific. The "biological pump" works efficiently in these areas compared to the mid ocean.

The ratio of silicon to calcium in organism-assimilated particles collected by deep ocean sediment traps is an indicator of the rate of removal of carbon-dioxide carbon from the upper ocean to the deep-ocean "sink." This ratio indicates there are two types of ocean areas depending on which element is dominant (see figure 2 above).