THE argument was clear for Hunter students striking in 2019 for climate change action from Australian governments.
The 2015 Paris Agreement, and an update in 2018, require governments around the world to limit global warming to 1.5 degrees Celsius by reducing carbon emissions to reduce the impact of climate change.
The goal requires human-caused emissions of carbon dioxide to fall by about 45 per cent from 2010 levels by 2030, and reach "net zero" by around 2050.
That goal comes with a time limit of a decade, a "global carbon budget" equation and a consequence for coal areas, including the Hunter.
Climate scientists including Australia's Professor Will Steffen say this means new coal reserves cannot be developed if the world is to limit global temperature rise.
"The fossil fuel industry cannot continue to expand if we are serious about tackling climate change," Professor Steffen said.
Arguments about jobs and the economy have to take second place to the future because the projected impacts of unfettered global warming are dire, he argues, backed by the findings of the Intergovernmental Panel on Climate Change.
Which is why Professor Steffen supports Hunter students calling on all Australians to help block Glencore's Glendell mine expansion.
Glencore, one of the world's leading coal producers, with a number of very large coal mines in the Hunter, wants to open up a new area for Glendell to more than double annual mine production until 2044. It will provide job security for 300 workers and hundreds of millions of dollars in economic benefits for the Hunter region and the state, Glencore said.
But on the weekend students and supporters, including Anglican priest Rod Bower and Edmund Rice Centre director Phil Glendenning, said catastrophic bushfires in NSW and Victoria showed Australians the future if we do not get serious about reducing greenhouse gas emissions.
The federal government and Prime Minister Scott Morrison have been strongly criticised on climate change, but it's the NSW government which has been approving Hunter coal mines without pause, despite the Paris Agreement obligations on Australia and its own "aspirational" net zero carbon emissions by 2050.
Glendell is a first test in a new decade.