Dan Smale, Marine Biological Association et Thomas Wernberg, The University of Western Australia
Marine heatwaves, like their land counterparts, are growing hotter and longer. Sea species in southeastern Australia, southeast Asia, northwestern Africa, Europe and eastern Canada are most at risk.
Everyone knows the Great Barrier Reef is in peril. But a continent away, Western Australia’s Shark Bay is also threatened by marine heatwaves that could alter this World Heritage ecosystem forever.
Jim Salinger, University of Tasmania et James Renwick, Te Herenga Waka — Victoria University of Wellington
Analysis of last summer’s heatwave shows it killed farmed salmon and decimated kelp forests, as well as shifting grape harvests and fish spawning times forward by several weeks.
Craig Stevens, National Institute of Water and Atmospheric Research et Ben Noll, National Institute of Water and Atmospheric Research
Marine heatwaves may become the new normal for the Tasman Sea and the ocean around New Zealand, and oceanographers are developing models to better predict their intensity.
Climate mitigation efforts are unlikely to be enough to save critical ecosystems like the Great Barrier Reef. We may need to consider more radical environmental engineering.
The 2016 bleaching event resulted in 30% mortality on the Great Barrier Reef, with many corals dying of the heat before they bleached and the loss of branching corals creating less complex reef structure.
Tropical coral reefs can be saved from climate change and other pressures, but the window of opportunity is closing. And reefs are guaranteed to be markedly different in the future.
A 10-week surge in ocean temperatures off the Western Australian coast has killed off large patches of kelp forest, the “biological engine” of Australia’s southern reefs.
This summer has seen Tasmania suffer through drought, bushfires, floods and the worst marine heatwave on record. Is this what life under a climate-changed future will be like?