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NASA: Deadly blooms in the Gulf of Mannar

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3 years ago

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For the past four years, water in the Gulf of Mannar has turned bright green in September and October as the population of a single-celled phytoplankton called Noctiluca scintillans soared. These large blooms of the marine dinoflagellates glow a spectacular shade of blue at night, but their presence can have deadly consequences for marine life by soaking up all the oxygen in the water and causing hypoxia and dead zones, said a report by NASA yesterday.

That’s what was happening on September 23, 2022, when the Operational Land Imager-2 (OLI) on Landsat 9 captured this image of whorls of N. scintillans discoloring waters in northern Sri Lanka and southern India near the Gulf of Mannar Marine Biosphere Reserve. The shallow water in this area normally teems with coral, reef fish, sea turtles, dolphins, dugong, and other marine life. But during N. scintillans outbreaks, fish carcasses line beaches and dead coral skeletons transform reefs.

“We saw particularly severe coral mortality and fish kill in 2019, but it happened in 2021 and 2022 as well,” explained Diraviya Raj, a researcher at the Suganthi Devadason Marine Research Institute in Tamil Nadu, India, and the lead author of a 2020 study about N. scintillans blooms in the Gulf of Mannar. “The 2020 bloom was short and did not harm corals, but the 2021 and 2022 events each lasted for two months, covered large areas, and caused severe damage.”

The earliest reports of N. scintillans blooms causing fish kills in the Gulf of Mannar date back to 1935, with occasional reports of the phenomenon in subsequent decades. However, the regularity and intensity of the blooms since 2019 seem to be something new. “We suspect that climate change has made the N. scintillans bloom an annual occurrence,” Raj said. “The water temperature level has been more than 30°Celsius (86°Fahrenheit) during the blooms, which is unusually high for the Gulf of Mannar in September-October.”

Living staghorn corals are brightly colored, while the dead corals in the photograph above—taken on November 17, 2021, near Manauli Island—had turned white and were covered with algal debris about a month after the bloom started to affect them. Fast-growing corals species such as Acropora, Montipora, and Pocillopora are the most vulnerable to N. scintillans blooms because they require the most oxygen to thrive.

Lines of dead fish, like those shown below, covered beaches on the islands of the Gulf of Mannar and the mainland near Mandapams and Keelakarai when the photo was taken on October 13, 2021. By analyzing water samples, Raj and colleagues confirmed that oxygen-depleted water triggered by the N. scintillans bloom was the cause of the fish kills and coral deaths.

Another team of researchers from the Central Marine Fisheries Research Institute in Mandapam Camp and the Indian Space Research Organization tracking the blooms found that 38 genera of fish were affected by the 2019 bloom and 43 genera by the 2021 bloom. Among them were parrotfish, rabbitfish, pufferfish, lesser sardines, needlefish, and tarpons, they noted in a study published in March 2023.

The 2021 bloom also killed large numbers of animals being raised in finfish farms, explained Ramesh Kumar, the lead author of the study. However, the team thinks it may soon be possible to warn fish farmers of N. scintillans blooms in advance, using improved satellite mapping abilities and new modeling techniques. That may allow farmers to harvest fish before blooms spread to coastal areas and cause widespread damage.


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A strong Technical and Vocational Education and Training (TVET) system equips individuals with practical, relevant, and future-oriented skills helping to innovate responsibly towards a greener and sustainable future – PM

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2026/03/26

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The Prime Minister, Minister of Education, Higher Education and Vocational Education Dr. Harini Amarasuriya participated as the Chief Guest in the international conference on ’Transforming TVET Systems for climate resilience and green jobs’ organized by Colombo Plan Staff College, Philippines together with the Ministry of Education, Higher Education and Vocational Education Sri Lanka on 24 th of March at Courtyard by Marriott Colombo, Sri Lanka.

The Conference serves as the flagship event of the five-day Regional Programme on “Transforming TVET for a Digital, Green, and Inclusive Economy” (23-27 March 2026), which continues throughout the week, bringing together representatives from CPSC member countries including Bhutan, Fiji, Malaysia, Maldives, Myanmar, Nepal, Philippines, Thailand, Pakistan, and Sri Lanka, fostering high-level dialogue and knowledge sharing on climate-resilient and green skills development.

The Conference features technical and plenary sessions on climate-responsive TVET systems, green skills development, national policy frameworks, and emerging technologies shaping industry transformation.

Addressing at the event, the Prime Minister emphasized the role of Technical and Vocational Education and Training (TVET) that equips individuals with practical, relevant, and future-oriented skills in addressing climate change and shaping a sustainable future.

The Prime Minister reaffirmed that this transformation remains a national priority for Sri Lanka. She stressed that education must go beyond knowledge dissemination to empower individuals with opportunities, dignity, and the capacity to contribute meaningfully to society.

She further emphasized the need to integrate environmental sustainability into education and training systems by embedding green skills in curricula, investing in modern training facilities, promoting innovation, and fostering collaboration between training institutions and emerging green industries.

Highlighting the importance of ensuring equity the Prime Minister further stated, that opportunities arising from the green transition must be accessible to all, including youth, young women, people with special needs, and marginalized communities.

Reaffirming Sri Lanka’s commitment to working closely with regional and international partnerships, the Prime Minister emphasized the importance of transforming them to actual benefits and partnerships.

The occasion was attended by the Secretary to the Ministry of Education, Higher Education and Vocational Education  Nalaka Kaluwewa, Additional Secretary (Vocational Training) Ms. Samanthi Senanayake Director General Colombo Plan Staff College Prof. Dr. Suresh K. Dhameja , TVET administrators, institutional leaders, policymakers, instructors, industry representatives, and international delegates from across the region and seniors officials and officials from Ministries.

(Prime Minister’s Media division)

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PM reviews progress of the committee appointed for the establishment of a National Nursing University

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2026/03/26

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A discussion to review the current progress of the special committee appointed under the government’s policy proposals to establish a National Nursing University aimed at elevating the nursing profession in Sri Lanka to degree level was held on 23rd of March at the Prime Minister’s Office under the patronage of Prime Minister Dr. Harini Amarasuriya.

During the meeting, the Prime Minister inquired into the progress made by the committee in relation to the establishment of the Nursing University and paid attention to the issues and views presented by the committee members.

Emphasizing that establishing a university is a long-term and complex process, the Prime Minister pointed out the importance of advancing this project in line with higher education standards, without hasty decisions, while also taking into account the existing conflicts and challenges within the university system.

The meeting was attended by the Vice Chairman of the University Grants Commission, Professor K. L. Wasantha Kumara, representatives of the All Ceylon Nurses’ Association, and officials from the Ministry of Health and Mass Media.

(Prime Minister’s Media Division)

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Heat Index at ‘Caution level’ in the Western, Sabaragamuwa, Southern and North-western provinces and in Anuradhapura, Mannar, Vavuniya and Monaragala districts

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2026/03/26

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Warm Weather Advisory
Issued by the Natural Hazards Early Warning Centre of the Department of  Meteorology
at 3.30 p.m. on 25 March 2026, valid for 26 March 2026.

The Heat index, the temperature felt on human body is likely to increase up to ‘Caution level’ at some places in the Western, Sabaragamuwa, Southern and North-western provinces and in
Anuradhapura, Mannar, Vavuniya and Monaragala districts.

The Heat Index Forecast is calculated by using relative humidity and maximum temperature and this is the condition that is felt on your body. This is not the forecast of maximum temperature. It is generated by the Department of Meteorology for the next day period and prepared by using global numerical weather prediction model data.

Effect of the heat index on human body is mentioned in the above table and it is prepared on the advice of the Ministry of Health and Indigenous Medical Services.

ACTION REQUIRED
Job sites: Stay hydrated and takes breaks in the shade as often as possible.
Indoors: Check up on the elderly and the sick.
Vehicles: Never leave children unattended.
Outdoors: Limit strenuous outdoor activities, find shade and stay hydrated.
Dress: Wear lightweight and white or light-colored clothing.

Note:
In addition, please refer to advisories issued by the Disaster Preparedness & Response Division, Ministry
of Health in this regard as well. For further clarifications please contact 011-7446491.

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