Reef monitoring stepped up as strong El Niño persists

Published: 30/11/2015

Marine managers and scientists will escalate their monitoring of the Great Barrier Reef over summer due to the risk of coral bleaching posed by a strong El Niño in the Pacific Ocean and climate change.

A pre-summer workshop held by the Great Barrier Reef Marine Park Authority (GBRMPA) has heard the highest risk period for bleaching on the Reef will be February and March 2016 because of heat stress from predicted above average sea-surface temperatures.

The workshop is convened each year by the agency to enable participants, including the Bureau of Meteorology, to discuss climate outlooks for the summer ahead, and the legacy of Reef health impacts from previous years.

GBRMPA’s Reef Recovery director David Wachenfeld said the information shared at the workshop would enable preparation for any weather-related impacts under the agency’s reef health incident response system.

“At this stage, the El Niño is the strongest one that we’ve had since 1997–98, and this poses a high risk of heat stress to coral on the Great Barrier Reef,” said Dr Wachenfeld.

“However, it’s important to remember that local weather conditions can have a big influence on sea surface temperatures. For example, high cloud cover and wave action can greatly reduce sun exposure and heat absorption by the sea, thereby mitigating bleaching.

“Whether coral bleaching occurs or not will depend on whether sea temperatures go beyond normal summer maximum temperatures and if they persist.

“We’re monitoring sea surface temperatures closely and will continue to work with the Bureau of Meteorology and the US National Oceanic and Atmospheric Administration over the coming months to forecast and assess coral bleaching conditions and help target in-water surveys.

“At this early stage, no significant bleaching has been observed on the Reef.”

Bureau of Meteorology senior climatologist Luke Garde said the outlook for the next three months pointed to above average sea surface temperatures and fewer than average tropical cyclones across the Great Barrier Reef.

“International climate models suggest the strength of the El Niño is approaching its peak, and will start to break down in the first quarter of 2016,” Mr Garde said.

“However, we would expect warm sea surface temperatures to persist until at least autumn 2016.”

Dr Wachenfeld said knowing where and when impacts may occur helps Marine Park managers respond to an event in a way that supports coral recovery.

“If bleaching occurs, we’ll consider what practical measures can be taken to support coral condition and recovery,” he said. “But even before such an event, the community itself has an important role to play in supporting and building the Reef’s resilience at a time when it faces this elevated risk of coral bleaching. This means following the zoning rules, not anchoring close to corals, and responsibly disposing of litter.

“They may seem like small actions, however they’re all vital in taking stress off corals, leading to a healthier and more resilient Reef.”

Experts at the workshop included Marine Park managers, climate and weather scientists, coral reef ecologists and water quality specialists from the Australian Institute of Marine Science, the National Oceanic and Atmospheric Administration, the Australian Research Centre of Excellence for Coral Reef Studies, the University of Queensland, and the Queensland Parks and Wildlife Service.

Name: GBRMPA media
Contact: (07) 4750 0846