A system of ocean currents circulates colossal ribbons of warm and cold water around the globe, creating climate patterns and facilitating the productive marine ecosystems that feed millions by distributing nutrients necessary to jumpstart the food chain. It would not be a stretch to say that ocean currents, which are driven by the planet’s movement and differences in water temperature and salinity, are essential to life on Earth as we know it.
So, given the magnitude of their importance – and our 300-plus-year history of mapping them – it’s a bit surprising that we humans had been overlooking one.
A new current flowing southward along the southwest coast of Madagascar has just been described by a team of French, Malagasy, and South African researchers after they apparently discovered it by accident.
According to Live Science, the oceanographers were surveying the waters of the Mozambique Channel between Madagascar and mainland Africa when they noted a curious flow of water. After analyzing the area using advanced satellite imagery, they determined that the movement could not be accounted for by known currents.
An initial analysis of the freshly named Southwest Madagascar Coastal Current (SMACC), published in Geophysical Research Letters, estimates the warm water current is less than 300 meters (984 feet) deep and less than 100 kilometers (62 miles) wide – quite diminutive compared to goliaths like the Antarctic Circumpolar Current or Pacific Equatorial currents.
Driven by the force of Southern Hemisphere trade winds licking at the ocean’s surface, the SMACC contributes to the coastal upwelling along southern Madagascar (alongside the East Madagascar Current) that supports a species-rich habitat.
At its endpoint, the water flows into the Agulhas Current, a major water transportation path that travels south along the coast of southeast Africa before performing a hairpin turn and moving due east, forming the boundary between the Indian and Southern Oceans.
Due to the wide-ranging impacts of ocean currents on both living and non-living systems, the researchers know that their work will soon be followed by investigations into the SMACC’s hand in weather patterns and global ecosystems. Computer-based models of how the SMACC may be affected by climate change will also aid scientists focused on climate mitigation.
“As such, the Southwest Madagascar Coastal Current has key implications for studies about the greater Agulhas Current system, remote connections between oceanographic systems, [processes underlying] upwelling systems, fisheries management, local livelihoods, and so forth,” the team wrote.
“The uncovering of the SMACC has significant implications for the improved broader understanding of ocean systems around the world.”
[H/T: Live Science]