OTZ Mixing Pump and Migration Pump

MIGRANT PUMP: The diel vertical migration (DVM) is a major part of the ocean’s BCP. As the sun sets each day, many animals living in the twilight zone—including fishes, gelatinous zooplankton, crustaceans, and others—rise up to the surface en masse to feed on carbon-rich plankton and other organisms. As the sun rises and the upper ocean is illuminated, they descend back to the relative safety of the twilight zone’s darker waters, where they stay until night comes again. Through that daily vertical migration cycle, organisms actively transport carbon. This phenomenon represents the largest migration of animal life on Earth. Although DVM may help to fast-track carbon out of the surface ocean and into deep water, scientists are only just starting to understand its full impact on global climate. (Samantha Chang and Eric S. Taylor, © Woods Hole Oceanographic Institution)