CO2 levels in the atmosphere have reached 421 parts per million, or 0.0421%, according to NASA. That's similar to the amount the person in the video claims is in the atmosphere.

However, the claim that humans are only responsible for 3% of that CO2 is wrong, according to Gavin Schmidt, a NASA climate scientist and director of the Goddard Institute of Space Studies.

In 1850, the atmospheric CO2 concentration was about 280 parts per million. The increase to the current level of 421 parts per million is all a result of human activity, Schmidt told USA TODAY in an email. source

So roughly a third, not 3%, of the CO2 currently in the atmosphere has been contributed by humans since 1850.

He lied.

Moreover, "Global temperatures and atmospheric CO2 levels are correlated" (contrary to what that disinformation in the video suggests):

Australia was responsible for about 1.4% of human emissions between 1850 and 2021, according to Carbon Brief. This is close to what is stated in the video. But, again, that's 1.4% of one-third of the amount of CO2 currently in the atmosphere, not 1.4% of 3% (or 1.3% of 3%) as claimed in the video.

Additionally, between 1990 and 2019, Australia's per capita CO2 emissions from industry, land use change and agriculture were among the highest in the world, outpacing the U.S., China and Russia, according to Climate Watch.

He lied about that too.

For climate change, total amount of CO2 is more important than proportion of CO2

The fossil fuel industry and that lying asshole want us to think that the proportion of CO2 is more important.