June 8 (UPI) -- New research suggests an alkalinizing agent could offset ten years of ocean acidification along the length of the Great Barrier Reef, buying the region's coral a bit more time as world governments scramble to slow anthropogenic carbon emissions.
For the study, published Tuesday in the journal Environmental Research Letters, scientists used high-resolution models to predict how an alkalinizing agent delivered via existing shipping infrastructure would influence acidity levels along the Great Barrier Reef.
Like so many other coral reefs around the world, the Great Barrier Reef faces a litany of threats, including marine heatwaves, invasive species and nutrient overloading. Ocean acidification, however, is perhaps the most pressing threat.
Ocean acidification disrupts the ability of coral to build and repair its protective exoskeleton. As ocean acidity levels increase, reefs are less likely to recover from coral bleaching events brought on by prolonged heatwaves.
"Amelioration of decades of [ocean acidification] on the [Great Barrier Reef] is feasible using existing infrastructure, but is likely to be extremely expensive, include as yet unquantified risks, and would need to be undertaken continuously until such time, probably centuries in the future, when atmospheric CO2 concentrations have returned to today's values," researchers wrote in the paper.
Some policy makers have suggested ocean acidification could be at least periodically reversed by injecting an alkalinizing agent, such as olivine, into the ocean water surrounding the Great Barrier Reef.
"The majority of the artificial ocean alkalinization modeling studies to date have focused on the potential for alkalinization as a carbon dioxide removal technique," researchers wrote. "Few studies have explored the role of alkalinization with a focus on offsetting the changes associated with ocean acidification at a regional scale."
Using a hydrodynamic-biogeochemical model tweaked to account for the idiosyncrasies of the Great Barrier Reef, researchers determined that an alkalizing agent released along the length of an already established shipping lane would reach the entirety of the reef.
The models showed that the release of 30,000 tons per day for a year would offset a decade of ocean acidification on 250 reefs under the present rate of anthropogenic carbon emissions.
Researchers determined such a project would sequester an additional 35,000 tons of carbon in the ocean per year, or 0.0001 percent of current global CO2 emissions, according to the study.