How jellyfish may be stirring the ocean
A new study suggests the movement of masses of tiny marine creatures could have as much impact as the wind or currents on ocean circulation.
Winds do it. Ocean currents do it. And now, it looks like tiny marine creatures can do it too – act collectively as a giant Mixmaster, bringing cold, nutrient-rich water from deep in the ocean to the surface, where other marine life can use the nutrients.
A pair of aeronautic scientists say they have shown how marine organisms ranging in size from tiny copepods to shrimp-like krill to jellyfish – known collectively as zooplankton – could play a vital role in stirring up the ocean.
If they’re right, marine organisms of all sorts may be responsible for as much deep-water mixing as winds and currents. And that could have implications for conservation concerns ranging from the health of fisheries to the unanticipated effects from climate change and ocean acidification.
The new study is part of a small but growing body of research that asks not how oceans affect marine life, but how marine life affects the oceans – particularly ocean circulation.
It's a topic "that looks like it may be significant but has largely been overlooked in the past," says William Dewar, a marine scientist at Florida State University in Tallahassee who focuses on ocean circulation and was not part of the research team. The new study, he says, "is a very nice contribution."
The importance of ocean mixing
The new insights, if correct, could have implications for understanding climate change effects.