GC082-0010
Climatic and Oceanographic Controls on Coral Bleaching Conditions in the Maldivian Region.
Climatic and Oceanographic Controls on Coral Bleaching Conditions in the Maldivian Region.
Monday, 14 December 2020
Poster
Abstract:
The frequency of coral bleaching events has been increasing in recent decades, due to the temperature rise registered in most ocean regions.
Their occurrence in the Maldivian Archipelago has been observed in the months following the peak of strong El-Niño events. Bleaching has not been uniform, and some reefs have been only marginally impacted.
We use satellite observations and a regional ocean model to explore the spatial and temporal variability of sea surface temperatures (SST), and quantify the relative magnitude of ENSO-related episodes.
We explore how and where ENSO events, both positive and negative, may modify the strength and duration of SST anomalies, and how the ocean circulation influences the distribution of ocean temperatures in one of the most pristine marine biodiversity hotspots on the planet.
The interaction between currents and the steep bathymetry is responsible for a local cooling with respect to the surrounding waters of about 0.2°C in the Archipelago. The cooling occurs during almost all the year, including the warmest months when bleaching events are most likely. This cooling largely reduces the frequency of mortality conditions.
Using a regional ocean model we further analyze the physical mechanisms involved, showing that the cooling seems to emerge due to the mixing associated with the strong shear around the bathymetry of the islands.
Their occurrence in the Maldivian Archipelago has been observed in the months following the peak of strong El-Niño events. Bleaching has not been uniform, and some reefs have been only marginally impacted.
We use satellite observations and a regional ocean model to explore the spatial and temporal variability of sea surface temperatures (SST), and quantify the relative magnitude of ENSO-related episodes.
We explore how and where ENSO events, both positive and negative, may modify the strength and duration of SST anomalies, and how the ocean circulation influences the distribution of ocean temperatures in one of the most pristine marine biodiversity hotspots on the planet.
The interaction between currents and the steep bathymetry is responsible for a local cooling with respect to the surrounding waters of about 0.2°C in the Archipelago. The cooling occurs during almost all the year, including the warmest months when bleaching events are most likely. This cooling largely reduces the frequency of mortality conditions.
Using a regional ocean model we further analyze the physical mechanisms involved, showing that the cooling seems to emerge due to the mixing associated with the strong shear around the bathymetry of the islands.