The latest comprehensive analysis of national plans to address climate change after 2020 shows that the world will not reach its target of keeping warming to below 2C off pre-industrial levels.
Instead, the globe could suffer a median rise of between 2.6 and 3.1C by 2100 according by the Intended Nationally Determined Contributions (INDCs) submitted in preparation for the 2015 climate talks in Paris.
While it is an improvement from current policy and no-policy scenarios, it still falls short of the 2C target, not to mention the hopeful goal of 1.5C warming.
Co-author Malte Meinshausen of the University of Melbourne said that the world will not keep its promise of limiting global warming to below 2C and 1.5C without boosting ambition.
"The international community achieved unparalleled success with the Paris Agreement -- charting out the common path towards a zero carbon economy in the second half of the century," he said, adding "But national policies now have to follow the international momentum."
To get the world onto an economically efficient 2 degree C pathway, the study points to additional initiatives in the solar energy, wind energy, forestry and methane sectors, targets for the international aviation and maritime transport sectors and development of sustainable biomass in combination with carbon capture and storage (CCS).
Helping countries implement bold conditional targets would also assist.
"The challenges associated with departing from the fossil fuel path are one side of the coin," Meinshausen noted, adding "But there is an immense opportunity on the horizon, if Australia embraces a vision of becoming an energy superpower in a zero carbon world."
The study appears in the journal Nature.
