Indian Ocean coral bleaching


Sea surface temperatures across the WIO are declining. This widespread cooling coupled with the onset of the SE monsoon winds marks the end of the bleaching season in the region


The Indian Ocean Dipole (IOD) and El Niño–Southern Oscillation (ENSO) remains neutral and are likely to stay in this state through the southern hemisphere winter. Model outlook however suggests a negative IOD may develop from mid-winter while ENSO is predicted to reach or exceed La Niña threshold during September or October. According to WMO, there’s a 60% chance for ENSO-neutral conditions to prevail through June-Aug and 40% La Niña rise during Sept-Nov period. See the full alert right.

For materials and guidance on responding to coral bleaching and mortality, visit this page. Bleaching alerts from 2009 to date are available further down the page, and more information is available at these links – background, and methods.

Indian Ocean Bleaching observations Dashboard 2016-2020 (Beta version) click to open the dashboard. Our earlier version is also available here

The dashboard shows bleaching records from 2016-2020 and will be updated frequently with observations using reports made via the bleaching report form (right), or at this link – https://goo.gl/forms/jP3Ke9cclt3VM9403

Data displayed here is updated to the global bleaching database maintained by the NOAA Coral Reef Watch programme.

Access maps for 2016 coral bleaching and mortality observations.

Report coral bleaching

Submit basic observations on coral bleaching through this embedded window, or go to the google-form at this link. All data will be submitted to the global bleaching form supported by the NOAA Coral Reef Watch programme, and made accessible on a WIO regional database under development.

Historical bleaching – 2009 to present

All past bleaching alerts, from 2009 to the current year, are in the window below. Click on the relevant year, or scroll left/right within each year for additional alerts. Alerts are published between January and May each year, with fewer alerts when bleaching risk is low.