It has been calculated that since the pre-industrial era our CO2 levels have risen by 50%. In May 2022, scientists at the Mauna Loa Observatory measured CO2 levels at a volcano in Hawaii. The results they collected concluded that the CO2 concentration levels have reached 421 parts per million (ppm). This is a major increase from the 280ppm CO2 concentration levels calculated from before the industrial revolution began.
Scientists have stated that these levels of CO2 concentration have occurred before, in the Pliocene. This is a period before hominids walked upright, trees grew in the Arctic to create forests, and sea levels reached 5-25 metres higher than they do in 2022.
This could suggest that the levels of CO2 in our atmosphere are becoming severely dangerous, if our sea levels were to rise to Pliocene levels, we would lose many cities around the world. Many of our governments globally are not reacting quickly enough to climate change, and if levels are replicating those from the Pliocene period, it may result in catastrophic problems for our planet.