The first global mass bleaching event
Bleaching occurred simultaneously across every major reef region during and after the very strong 1997-98 El Nino, the first time the phenomenon had been observed at global scale rather than as a set of local events. The widely cited assessment published in 2000 estimated that around sixteen per cent of the world's reef-building corals died. Losses were extremely uneven: parts of the western Indian Ocean, including the Maldives and the Seychelles, lost the great majority of their shallow coral, while other regions came through with modest damage. The event established both that bleaching was a global phenomenon and that the ocean's heat, not any local pressure, was the agent.
Historical — it happened, and the record is settled.
Subjects
- Coral bleaching · ecological phenomenon · Global tropical reefs · not located
- Reef-building corals (Scleractinia) · species_group · Tropical and subtropical shallow seas, broadly 30 degrees N to 30 degrees S · not located
- Zooxanthellae (Symbiodiniaceae) · species_group · Global tropical and subtropical shallow seas, inside host tissue · not located
- El Niño–Southern Oscillation (ENSO) · natural phenomenon · Tropical Pacific
Evidence
Partly verified — Core facts are sourced; some optional detail is deliberately absent.
Status of Coral Reefs of the World: 2000
Around sixteen per cent of the world's reef-building corals died in the 1998 global bleaching event, with losses very unevenly distributed and most severe in the western Indian Ocean. V55 verification basis: not consulted; the sixteen per cent figure is the widely repeated headline of this report and is stated from the producing model's knowledge, not read from the report. The regional breakdown behind it was not checked.
Global Coral Reef Monitoring Network, edited by Clive Wilkinson; Australian Institute of Marine Science · 2000 · Partly verified
Wilkinson, C. (ed.) (2000), Status of Coral Reefs of the World: 2000, GCRMN / AIMS — the assessment of the 1998 global bleaching event.
Recorded on Coral bleaching
- Darwin publishes The Structure and Distribution of Coral Reefs
- The first global mass bleaching event
- A published projection that reefs would bleach faster than they could recover
- The third global bleaching event
- Mass bleaching on the Great Barrier Reef
- A second consecutive year of mass bleaching on the Great Barrier Reef
- The interval between severe bleaching events is measured, and it has collapsed
- The coral symbionts are reclassified into a family of genera
- The fourth global bleaching event is confirmed
- El Niño Advisory in effect at the July 2026 CPC discussion
Related
Related because they share a subject in the Atlas — never because the text looks similar.
- El Niño Advisory in effect at the July 2026 CPC discussion · 2026-07-09
- The fourth global bleaching event is confirmed · 2024-04
- The interval between severe bleaching events is measured, and it has collapsed · 2018-01
- The coral symbionts are reclassified into a family of genera · 2018
- A second consecutive year of mass bleaching on the Great Barrier Reef · 2017
- Mass bleaching on the Great Barrier Reef · 2016-03 to 2016-04
- The third global bleaching event · 2014–2017
- A published projection that reefs would bleach faster than they could recover · 1999