TEMPO.CO, Bangkalan - The natural occurrence that happened recently beneath the renowned Suramadu Bridge is scientifically identified as a halocline between two bodies of water. The halocline causes a plume where the freshwater rushing from the river beneath Suramadu meets the salinity of seawater.

Oceanography explains halocline as a vertical zone in the oceanic water column in which salinity changes rapidly with depth that creates a stunning visual appearance of two separate bodies of waters.

Lately, this natural occurrence became viral after a motorcyclist passing the bridge recorded it and posted it online on Tuesday, March 19.

The person who recorded it, Arif (30), a resident of Bangkalan District, said that he was not struck by the phenomena since it often happens near his fishermen village of Karbungoh. This village is located close to the bridge.

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The only particular difference from the water separation he recorded was that it managed to form near the coastline, which attracted even more attention from local people.

“This time, the freshwater reached dead center beneath the bridge. It was much clearer and took longer before [the body of waters] merged together,” said Arif to Tempo.

According to Alan Koropitan, IPB oceanographer and member of the Young Scientists of Indonesia (ILMI) said that the river plume often happens during high rainfall season which causes the increase of water flow from the river.

“At a glance, I identify it as a plume with differing water densities. It’s possible that high water flow from the river [caused by increasing rainfall], the sediments rushed by the river flow were clearly visible,” said Alan.

MUSTHOFA BISRI