The previous decade was the warmest decade on record and each decade in Australia since the 1940's was warmer than the previous decade. The cause for this is due to human activity that has increased the concentration of Carbon Dioxide (CO₂) in the atmosphere. If left unabated, global warming will continue to accelerate as the polar caps melt, reflecting less sun light back into space, and the perma-frost melt releasing vast amounts of methane into the atmosphere.

Prior to the industrial revolution, atmospheric levels of CO₂ were between 200 and 300 PPM (Parts per Million). In 2021 the amount was about 416 PPM with the expectation that this will continue to rise unabated under a Business As Usual (BAU) scenario. It's been argued that the ideal range is between 280 and 330 PPM, which is optimal for creating comfortable temperatures and takes into consideration existing infrastructure.

Global warming is predominantly blamed on inductrial activity (CO₂), agricultural activity (methane CH₄) and deforstation. For the sake of convenience, the global warming potential of all gases is compared to CO₂ and referred to a Carbon Dioxide Equivalent CO_2e.

Total global greenhouse emissions over the 2021 calendar year were thought to be about 55GT of CO_2e. With net-zero commitments and electricity and hydrogen replacing fossil fuels, it is expected that emissions will flatten in the next few decades. This, however, might not be enough to slow down global temperature increase.

Australia's CO₂ emissions over 2022 were about 466 MT with the following trends in the various sectors when compared with previous year:

We are one of the world's highest emitter of greenhouse gases on a per capita basis at just over 15T per person; however, in 2021 Australia represented 1.1% of the world's total emissions.

Australia has emission reduction targets of 43% below 2005 levels and net zero emissions by 2050.