Offshore carbon capture and storage (CCS) technology is a new threat to the world's oceans and a dangerous distraction ahead of climate talks, legal experts say.
The independent Centre for International Environmental Law issued research on Thursday that found storing greenhouse gas emissions in depleted wells in the seabed is no solution to fossil fuel pollution.
Over 50 new offshore CCS projects have been announced worldwide, potentially leading to a 200-fold increase in annual carbon injection beneath the seabed.
"The risks associated with offshore CCS put more pressure on the world's already-stressed oceans," researchers said.
"Offshore CCS represents the next frontier of ocean abuse by the fossil fuel industry."
The centre's analysis found many projects are being used to justify the expansion of fossil fuel production, rather than offsetting emissions from existing fields.
The database covers dozens of offshore projects, including in Australia, the United States, the United Kingdom, Norway, and the United Arab Emirates.
"Whether onshore or offshore, injecting carbon under the Earth's surface has the potential to contaminate groundwater, cause earthquakes, and displace deposits of brine, which can be toxic," the report said.
"Carbon capture introduces new environmental, human rights, health, and safety hazards beyond those posed by climate change."
Proposed storage hubs are concentrated in areas with legacy oil and gas wells, increasing the risk of leaks and other accidents that could pose major hazards to sensitive marine organisms and add to the ocean acidification crisis.
Offshore CCS is also heavily dependent on government subsidies, which diverts significant public funds away from proven solutions and towards polluters, the report said.
The research comes ahead of the next round of international climate talks, COP28, where leaders will undertake a global stocktake on progress to curb global warming.
Australian governments rely on CCS to meet international emissions reductions commitments while extending the nation's economic prosperity from export earnings on vast fields of liquefied natural gas (LNG).
But CCS projects have repeatedly fallen short of targets, raising doubts about their feasibility and safety, the report warns.
Federal Labor has released new areas for exploration for offshore CCS in Commonwealth waters off Western Australia, Victoria and Tasmania to help achieve net zero emissions by 2050.
The technology is also at the heart of Santos' plans to store emissions in a massive project in the Timor Sea.
New laws passed on Monday allow LNG majors to pump emissions across international boundaries for storage in sub-seabed geological formations.
Projects from domestic producers were already allowed under existing law.
Santos says CCS needs to be scaled up to support future production of low-carbon gas to support the energy transition.
Australia's biggest such project, Chevron's Gorgon carbon trap on Barrow Island off the northwest coast of WA, has captured millions of tonnes of carbon to date but remains well below injection targets.