In case you are wondering if seawater appears blue due to the change in its colour, well the reality is very different.
From Mumbai’s Juhu to Goa’s Betalbatim, India’s West Coast is dazzling with stunning blue tides at night these days. The reason for this picturesque phenomenon? Bioluminescence. But here’s a catch: While many may find these blue waves quite romantic, researchers say that there’s nothing to cheer about. According to a report by the Indian Express, the reason for such blue tide can range from heavy rainfall to a high amount of sewage discharged into the sea. Talking to the IE, Professor Gurudas Nulkar from the Symbiosis International University said that the real cause of such blue tides is the low quality of the water in the ocean. When the oxygen level goes down and the presence of nitrogen increases, seawater witnesses such occurrence.
In case you are wondering if seawater appears blue due to the change in its colour, well the reality is very different. The blue colour behind the phenomenon is due to the presence of aquatic plants! Yes, these unicellular organisms are actually water plants that live in the deep sea. Scientifically they are known as phytoplanktons. These marine plants also called dinoflagellates emit blue light, which is part of their defence mechanism. When the surface in the shallow waters near the beaches, the waves disturb them, causing these micro plants to emit blue light as their natural anti-predatory mechanism.
Though beaches in Japan and the United States are known for such blue tides, India’s West Coast has been witnessing such occurrences since 2016. The IE report said that apart from Juhu, beaches in Ratnagiri and Devgad also reported about the blue tides last week. Onlookers also saw blue waves on Goa’s Betalbatim beach also.
Environmentalists have long said that these blue tides are an indicator of El Nino effect. This essentially means warmer oceans and increased pace of climate change. The IE report said that the fewer blue tides would not cause much harm to the local aquatic circle. However, in case these marine plants multiply in number, they can disturb the local ecology. It can ultimately result in the death of fish in the seawater.