Australian Oceans Face Unprecedented Changes by 2040, New Study Warns
Australia’s marine environments are predicted to undergo drastic changes by 2040 due to increasing global temperatures, according to a recent study. This transformation is expected even if substantial reductions in carbon emissions are achieved.
Researchers from Australia have conducted models exploring various oceanic conditions across different emission scenarios, ranging from current levels to both high and low emissions. The study suggests that within 15 years, marine ecosystems will confront severe heat, depletion of oxygen, and increased acidity.
Prof David Schoeman from the University of the Sunshine Coast, a co-author of the research published in Earth’s Future, stated, “The average year from 2040 onwards will be more extreme than the most extreme year that we’ve experienced up until 2015.”
Alice Pidd, the lead author of the study and also from the University of the Sunshine Coast, noted that marine species are already migrating towards cooler waters near the poles. This shift is happening at an average rate of 59km per decade, with some species, such as the kingfish in eastern Australia, moving as much as 102km every ten years.
“This gradual ratcheting up is punctuated by extreme events such as marine heatwaves that are becoming increasingly more frequent, intense, and prolonged,” Pidd explained. “As our oceans acidify [and] lose oxygen, the life they support is under increasing pressure to move, adapt or die. We’re already seeing this in action.”
The research indicates that marine protected areas are equally vulnerable to these threats as non-protected regions. The authors advocate for expanding protected zones to encompass climate refuges, locations where biodiversity stands a better chance of enduring.
Potential climate refuges, areas anticipated to experience minimal change, are primarily situated along the southern and southwestern coastlines under scenarios meeting or exceeding the Paris climate agreement. However, these refuges diminish rapidly under scenarios of higher emissions.
The research team emphasized the urgency for decisive actions to reduce carbon emissions, aiming to delay or mitigate the anticipated climate impacts. “We’re entering uncharted territory and marine biodiversity will be under increased pressure to adapt,” Pidd stated. “The past is no longer a good guide to the future.”
Prof Jodie Rummer, a marine biologist at James Cook University who was not involved in the study, highlighted that ocean warming, oxygen loss, and acidification form a “deadly trio” for marine life. She noted, “We’ve seen differences in behaviour due to temperature changes that the Great Barrier Reef, coral reefs, and tropical ecosystems are facing already.”
Rummer emphasized the need for evolving conservation strategies, stating, “The rules that we’ve been relying on for ocean protection and conservation, they’re going to have to evolve.”
The chief executive of the Australian Marine Conservation Society, Paul Gamblin, who was not part of the study, remarked that evidence supporting the findings is becoming increasingly apparent. The recent year, described as a “reckoning,” saw simultaneous bleaching of the Great Barrier Reef and Ningaloo, a mass fish kill off the Pilbara coast, unprecedented sea surface temperatures, and the ongoing impact of South Australia’s algal bloom.
Gamblin stressed, “There’s almost nowhere to hide,” adding that current government deliberations on new national nature laws must consider the full climate impacts of new proposals.
He further commented on the need for updating Australia’s environmental laws, which were established 26 years ago, to reflect the rapid and significant climate impacts on oceans. “Our laws need to reflect that, and Australia’s response generally needs to reflect that sobering reality,” Gamblin concluded.
Original Story at www.theguardian.com