A survey of various islands of Lakshadweep revealed that a large proportion of hard coral species have undergone severe bleaching due to the prolonged period of marine heat wave affecting the region since October 2023.
Marine heatwaves are rare extreme weather events that involve abnormally high ocean temperatures for a prolonged period.
These temperatures often exceed the 90th percentile of typical regional ocean temperatures based on historical data.
In Lakshadweep, the degree heating week (DHW) indicator, which measures accumulated heat stress, has risen above 4 degrees C-week.
According to the National Oceanic and Atmospheric Administration (NOAA), this level of DHW poses a significant risk of coral bleaching, threatening the region's diverse marine ecosystems.Dr KR Srinath, senior scientist at CMFRI, said such heat stress levels indicate a serious threat to coral health, leading to mass bleaching, where corals lose symbiotic algae (zooxanthellae), making them Essential nutrients are not available and their survival is in danger.
"If DHW continues to rise, reaching more than 12 degrees C-week, it could lead to an unprecedented biodiversity crisis due to multi-species mortality," Dr Srinath said.
According to Dr. Shelton Padua, senior scientist at CMFRI, the primary cause of these marine heatwaves is extreme heat atmospheric transfer as well as changes in ocean currents, causing abnormally high water temperatures.
Dr. Padua said, “From October 27, 2023, the temperature in the Lakshadweep Sea spanning from 80.0 to 12.0 latitude and 71.0 to 75.0 east longitude is continuously increasing by more than 1 degree Celsius above normal.”
Noting that the health of marine ecosystems is integral to the livelihoods of coastal communities, impacting the tourism and fisheries sectors, Dr. Srinath said the ongoing marine heat wave could have a critical impact by disrupting their vital ecosystem services. There is a possibility of financial loss.“The death and degradation of coral reefs can threaten coastal communities, making them vulnerable to the effects of sea level rise aggression,” said D Srinath.
CMFRI is actively conducting studies to better understand the ecological changes affecting coral reefs and has also initiated a comprehensive national project aimed at examining the resilience capacity of various coral reefs in India.
Marine heatwaves are rare extreme weather events that involve abnormally high ocean temperatures for a prolonged period.
These temperatures often exceed the 90th percentile of typical regional ocean temperatures based on historical data.
In Lakshadweep, the degree heating week (DHW) indicator, which measures accumulated heat stress, has risen above 4 degrees C-week.
According to the National Oceanic and Atmospheric Administration (NOAA), this level of DHW poses a significant risk of coral bleaching, threatening the region's diverse marine ecosystems.Dr KR Srinath, senior scientist at CMFRI, said such heat stress levels indicate a serious threat to coral health, leading to mass bleaching, where corals lose symbiotic algae (zooxanthellae), making them Essential nutrients are not available and their survival is in danger.
"If DHW continues to rise, reaching more than 12 degrees C-week, it could lead to an unprecedented biodiversity crisis due to multi-species mortality," Dr Srinath said.
According to Dr. Shelton Padua, senior scientist at CMFRI, the primary cause of these marine heatwaves is extreme heat atmospheric transfer as well as changes in ocean currents, causing abnormally high water temperatures.
Dr. Padua said, “From October 27, 2023, the temperature in the Lakshadweep Sea spanning from 80.0 to 12.0 latitude and 71.0 to 75.0 east longitude is continuously increasing by more than 1 degree Celsius above normal.”
Noting that the health of marine ecosystems is integral to the livelihoods of coastal communities, impacting the tourism and fisheries sectors, Dr. Srinath said the ongoing marine heat wave could have a critical impact by disrupting their vital ecosystem services. There is a possibility of financial loss.“The death and degradation of coral reefs can threaten coastal communities, making them vulnerable to the effects of sea level rise aggression,” said D Srinath.
CMFRI is actively conducting studies to better understand the ecological changes affecting coral reefs and has also initiated a comprehensive national project aimed at examining the resilience capacity of various coral reefs in India.
