Vidhi Bubna, a 23-year-old scuba diver and creator of Coral Warriors, contacted me a few months ago because we shared an interest in the climate issue, oceans, and biodiversity.
She had a harrowing story to tell.
“I was astonished to witness widespread bleaching of corals when I made my first dive in the Andamans Islands last year,” she says. “It was like a graveyard down there.”
This is concerning since corals are an essential part of the undersea environment. Because corals are home to hundreds of marine species, they safeguard coastal regions by lowering the strength of waves hitting the coast and providing a vital income source for millions of people.
What Bubna saw is widely established in scientific studies: coral reefs are among the most vulnerable ecosystems on the planet, owing partly to unprecedented global warming. According to UNESCO, if humans continue to release greenhouse gases at their current rates, coral reefs in all 29 reef-containing World Heritage sites would be extinct.
Coral bleaching and marine heatwaves
Speaking to 60-odd environment journalists stated that his team has observed a significant rise in marine heatwaves, which has been assisted by fast warming in the Indian Ocean.
Marine heatwaves are periods of exceptionally high temperatures in the ocean that cause coral bleaching, seagrass damage, and the loss of kelp forests, all of which harm the fisheries industry.
An undersea investigation found that following the May 2020 marine heatwave, 85 percent of the corals at the Gulf of Mannar along the Tamil Nadu beach were bleached.
These marine heatwaves, according to Koll, were once uncommon in the tropical Indian Ocean but have now become an annual occurrence. The western Indian Ocean Region witnessed the most extraordinary rise in marine heatwaves, around 1.5 occurrences per decade, followed by the North Bay of Bengal, which suffered a 0.5 event per decade increase.
Marine heatwaves like The Blob, which were first observed in 2013, caused catastrophic mortality in marine animals and birds and the collapse of fisheries and aquaculture in the United States and Korea. However, according to Koll, there has been no research on how it has affected India/South Asia.
According to his team’s findings, the western Indian Ocean suffered a fourfold increase in marine heatwaves between 1982 and 2018. The number of marine heatwaves in the North Bay of Bengal increased by two to thrice.
Koll also cautioned that as the seas warm (the oceans absorb 93 percent of the heat from global warming), the number and severity of cyclones and severe rains would increase.
The effect on the monsoons
Koll’s team’s research has shown for the first time that there is a strong relationship between marine heatwaves and atmospheric circulation and rainfall.
It revealed that marine heatwaves in the western Indian Ocean and the Bay of Bengal are causing drying conditions across the central Indian subcontinent. At the same time, according to Koll, there is a significant rise in rainfall over south peninsular India due to the heatwaves in the North Bay of Bengal. These alterations result from the heatwaves’ modification of the monsoon winds.
All climate model estimates indicate that the Indian Ocean will continue to warm in the future. This, according to Koll, is expected to exacerbate marine heatwaves and influence monsoon rains.
This implies that India’s ocean observing arrays will need to be improved to track these phenomena effectively. Weather models will need to be updated to foresee the problems posed by a warming globe.
Suppose marine heatwaves threaten to modify India’s rainfall pattern and impact marine biodiversity. In that case, India must spend extensively in strengthening its monitoring capability and climate resilience and adaptation initiatives.
The authored article is written by Sejal Wakkar and shared with Prittle Prattle News exclusively.
