(Updated: June 17, 2024)
On April 15, 2024, NOAA (in partnership with the International Coral Reef Initiative) confirmed the world has been experiencing a global coral bleaching event. Bleaching-level heat stress, as remotely monitored and predicted by NOAA Coral Reef Watch (CRW), has been -- and continues to be -- extensive across the Atlantic, Pacific and Indian Ocean basins.
Since early 2023, mass coral bleaching has been confirmed in 67 countries and territories in the Atlantic, Pacific, and Indian Oceans. As of this writing, the most extreme accumulated heat stress (Degree Heating Weeks [DHW] ≥ 16°C-weeks; Bleaching Alert Level 4 or higher) is active at reef sites in the west-central equatorial Pacific.
This is the fourth global coral bleaching event (a.k.a., GCBE4) on record -- following the 1998, 2010, and 2014-2017 global events -- and the second in the last 10 years. The 2014-17 global event (GCBE3) is still considered the longest, most widespread, and most damaging coral bleaching event on record. During that three-year event, more than 65.7% of the world's coral reefs (i.e., satellite pixels containing coral reefs) experienced bleaching-level heat stress. On May 23, 2024, the GCBE4 surpassed the extent of the GCBE3. As of this writing, more than 70.7% of coral reefs worldwide have been impacted by bleaching-level heat stress since January 1, 2023.
As NOAA and its partners work to document the extent and severity of mass bleaching on coral reefs around the world, the GCBE4 also provides an opportunity for NOAA CRW to compare field data of coral bleaching and mortality with its operational daily global 5km-resolution satellite coral bleaching heat stress data products, to help improve product performance, where possible, for our extensive and diverse user community worldwide. To do this, we need your help!
**To contribute coral bleaching data and observations (including reports of NO bleaching) to our ongoing effort, please do the following:**
1. E-mail your data files (in Excel, Word, etc.) directly to coralreefwatch@noaa.gov, OR
2. Enter your data into Coral Reef Watch's Google Form, OR
3. Download Coral Reef Watch's quantitative observations questionnaire (below), enter your data, and e-mail the completed questionnaire to coralreefwatch@noaa.gov.
NOAA Coral Reef Watch Quantitative Observations Questionnaire
(Excel spreadsheet, 13kb, Revised Sep 05, 2023)
What Can We All Do?
Predictions pose a daunting future, where even the most conservative estimates suggest mass coral bleaching could occur annually on the majority of coral reefs worldwide by 2050. Increased collaboration among coral reef stakeholders is vital given the critical state of reefs all over the world, and their ecological, economic and societal benefits. In addition to reducing local threats to coral reefs, galvanizing global urgency and action to reduce atmospheric carbon dioxide (i.e., the root cause of rapid anthropogenic climate change) is critical to strengthen conservation and restoration efforts.
