My understanding is that, as in Canada, most environmental assessment activity is actually undertaken at the state level--the provincial level in Canada--so the states have the primary authority and the federal Government of Australia does not get involved so much in environmental assessment activity.
But there is this provision in the federal Australian legislation that allows the federal government to undertake an environmental assessment. They can do that when they make a determination that it is a matter of national significance. Some of the areas that are considered to be nationally significant are laid out in that legislation. Climate change wasn't one of them, but there are other matters that were.
My interest in that law is really based on the idea that a national government should have some discretionary authority to assess projects that are in the national interest even though they may not otherwise be captured by some law list trigger.
An example is given of an in situ oil sands project: a huge amount of greenhouse gas emissions. As a country we're committed at the provincial level, the federal level, etc., to reduce our greenhouse gas emissions. Shouldn't the federal government have a seat at the table? Or shouldn't the federal government be able to require an environmental assessment in that situation?
Australia took this approach. It may be of interest in terms of an amendment to CEAA.