A recent study has identified significant impacts of the Madden-Julian Oscillation (MJO) and El Niño Southern Oscillation (ENSO) on coral bleaching events in the Great Barrier Reef (GBR).
The Great Barrier Reef, spanning nearly 350,000 square kilometers along Australia’s northeast coast, is the largest coral ecosystem globally.
“I’d often heard in the media that during El Niño periods the GBR is more likely to experience bleaching. Then during 2022, the reef experienced mass bleaching during a La Niña period, and it was reported that La Niña should mean cooling in the GBR,” Gregory said.
“However, in my research, I had examined this relationship and not found a strong connection between the ENSO index and ocean temperatures in this region. This motivated me to understand other drivers that could be influential.”
“The MJO, as the leading driver of sub-seasonal weather variability, seemed like an important one to consider. While ENSO provides insight into the expected synoptic states, it lacks details of anticipated sub-seasonal weather variability at local scales.”
These findings underscore the need for comprehensive forecasting models that include both ENSO and MJO impacts to better predict and manage coral bleaching events.