A sea breeze can carry the scent of the ocean inland for miles, and the source of that smell is a perfume made from living corals.
Biologists already knew that reef-building corals serve as the planet’s main producer of dimethylsulphoniopropionate (DMSP), a chemical that serves as a seed for clouds and gives the ocean its unique scent. However, they thought DMSP only came from the algae living with the coral animals.
Recently, marine scientists discovered that the tiny animals themselves also produce the chemical. Young coral animals, or polyps, caused DMSP levels to increase by 54 percent in an experiment documented in the journal Nature.
“The characteristic ‘smell of the ocean’ is actually derived from this compound, indicating how abundant the molecule is in the marine environment. In fact we could smell it in a single baby coral,” said study co-author Cherie Motti, an Australian Institute of Marine Science (AIMS) chemist, in a press release.
When the researchers turned up the heat, the polyps produced even more DMSP. Levels increased by 76 percent when the coral suffered in uncomfortably warm water.
Higher surface water temperatures threaten corals globally, along with declining water quality, ocean acidification, and other menaces. Coral die-offs could cause DMSP levels to spike at first and then crash.
DMSP can serve as the seed, or nucleus, for cloud formation. So alterations in levels of the chemical could influence cloud cover.
“Cloud production, especially in the tropics, is an important regulator of climate — because clouds shade the Earth and reflect much of the sun’s heat back into space,” said lead author Jean-Baptiste Raina, a marine scientist at AIMS, in a press release. “If fewer clouds are produced, less heat will be reflected — which ultimately will lead to warmer sea surface temperatures.”
With warmer surface waters heat-stressing and ultimately bleaching corals, this could create a negative feedback loop with the potential to deodorize the ocean.
IMAGE: A coral reef in shallow water (Jim Maragos, U.S. Fish and Wildlife Service, Wikimedia Commons)