SEA SURFACE TEMPERATURE BEFORE AND AFTER THE CORAL BLEACHING EVENT AND CROWN-OF-THORNS-SEASTAR (COTS) OUTBREAKS IN PULAU LAYANG LAYANG, MALAYSIA MOHD AZAMUDDIN MOHD HASSAN(a*), EJRIA SALEH(a), DANIELLA HAN(a), IVONNE MILICHRISTI RADJAWANE(b) GANDHI NAPITUPULU(b)
a) BORNEO MARINE RESEARCH INSTITUTE UNIVERSITI MALAYSIA SABAH, 88400 KOTA KINABALU, SABAH, MALAYSIA
*azamuddinums[at]gmail.com
b) Department of Earth Sciences, Faculty of Earth Sciences and Technology, Institut Teknologi Bandung, Bandung, Indonesia
Abstract
Sea Surface Temperature SST is a strong indicator of marine productivity and pollution. It influences the dynamics of climate patterns and impacts marine life and ecosystems. During the Covid-19 pandemic 2019 and 2020, massive coral bleaching events and crown-of-thorns-seastar COTS outbreaks have occurred at Pulau Layang Layang, Malaysia. However, no study was carried out due to the movement control order imposed by the Malaysian government and its remote location, about 272 km from Sabahs mainland. Nevertheless, the advancement of todays technology makes it easier to obtain SST data from satellites. The objectives of this paper are to identify SST at different seasonal monsoons and to determine the SST in Pulau Layang Layang during and after the coral bleaching event. The monthly SST data 2020 to 2022 was retrieved from MODIS Level 3 SST Thermal IR 8 Day 4km V2019.0 at the lagoon and offshore of Layang Layang Island. In-situ SST measurements were obtained from the tide gauge between 20th June 2022 and 26th June 2022. During the Northeast and Southwest monsoons, the average SST was 28.20 degree C and 30.45 degree C, respectively. However, the average SST was increased to 30.92 degree C between May to September 2020 during the SWM which may contribute to massive coral bleaching on the island. The warmer sea temperature is an important co-factor promoting COTS outbreaks. The SST back to normal in 2022 where the in-situ and satellite data were less than 30.05 degree C. However, the landscape of the coral reefs was changed, and may take years to recover to the original condition.
Keywords: Sea surface temperature- Coral reef- Moonsoon- Pulau Layang Layang
