An emissions-impact calculation method used by the Intergovernmental Panel on Climate Change (IPCC) has been employed to assess the amount of warming a single Australian fossil fuel project will cause based on its projected CO2 emissions, and the follow-on impacts to human health and the environment.
A Bushfire in Western Australia. Credit: Philip Thurston
The study, published in Climate Action and including a researcher from the University of Adelaide, used the Transient Climate Response to CO2 Emissions (TCRE) approach to estimate the impact of the 876 million tonnes of CO2 emissions expected from the recently approved Scarborough gas project, located offshore of northwest Australia, throughout its projected 31-year lifespan.
"The TCRE approach builds on the IPCC's statement that every additional tonne of CO2 emissions adds to global warming," says Dr Georgina Falster, from the University of Adelaide's School of Physics, Chemistry and Earth Sciences.
"TCRE facilitates a simple but highly robust translation of a particular amount of CO2 emissions into the equivalent amount of global warming that those emissions are directly responsible for."
Using TCRE, the team estimates the 876 million tonnes of CO2 emissions from the Scarborough project will cause 0.00039°C of additional global warming, with a 66-100 per cent likelihood of causing global warming of between 0.00024°C and 0.00055°C.
"While the estimate might seem small, the impacts of that warming are not," says Dr Falster.
"An additional warming of 0.00039°C would expose 516,000 people to unprecedented extreme heat, and force 356,000 people outside the climate niche that has allowed humanity to thrive in recent millennia.
"In Europe alone, we would expect this one project to cause 484 additional deaths from extreme heat by the end of this century.
"In Australia, approximately 16 million corals in the Great Barrier Reef would be lost in each new mass bleaching event, which would occur more frequently due to the additional global warming as a consequence of the Scarborough project's emissions."
Bleached staghorn coral in the Great Barrier Reef. Credit: Matt Kieffer (CC BY-SA 2.0).
The researchers calculated that by 2049 the anticipated Australian emissions from the Scarborough project alone will comprise almost half (49 per cent) of Australia's entire annual CO2 emissions budget.
"These findings contrast sharply with claims that individual fossil fuel projects will have negligible impacts," says contributing author Associate Professor Andrew King, from the University of Melbourne.
"In this case study alone, it is shown that the additional warming caused by CO2 emissions from the Scarborough project will persist for multiple decades to centuries, and cause long-term environmental and social impact."
The research team highlights that the Scarborough project is just one case study and these same impact calculations based on TCRE could be performed for all new and renewed Australian fossil fuel projects. They say this approach should be used to assess the impacts of all future projects.
"This research provides a science-based foundation that can be employed by companies and governments in quantifying the consequences of fossil fuel production and use, and in assessing whether these projects fall within acceptable levels of environmental and societal risk," says contributing author Dr Nicola Maher, from the Australian National University.
Importantly, the framework allows for better accounting by companies who propose new projects.
"Companies proposing new or extended fossil fuel projects must better account for the impacts of their projected emissions. It is no longer defensible to simply state that their consequences will be negligible," says contributing author Professor Sarah Perkins-Kirkpatrick, also from the Australian National University.
