Why is it, that humanity steers knowingly towards its own exctinction and the destruction of the planet?
Do you know how much CO2 you are releasing into the air each year? As a Swiss around 5 tonnes, as an American more than 20 tonnes. If you're living in Burundi, chances are that you aren't producing much more CO2, than from the air you breathe. Despite there being still some fools, idiots and profiteers proclaiming the opposite, man made climate chance is a scientifically proven fact. Our planet is heating up because we release carbon dioxide and other gases, that were formerly in solid or liquid state (mostly as coal or oil), into the atmosphere. Scientific evidence for warming of the climate system is unequivocal. To still question or deny this is about as absurd as denying gravity.
Global climate change will have profound implications for the quality of the life of hundreds of millions of people and it will globally increase conflicts as well as mass migrations. On top, it will diminish our flora and fauna; many scientist already call it the sixth mass extinction in the history of our planet. About a quarter of CO2 is absorbed by the oceans, leading to severe acidification of the seas and resulting in the destruction of coral reefs and having a dramatic effect on calcifying creatures like plankton. Unfortunately these creatures are the foundation of the oceanic food chain. When shelled organisms are at risk, the entire sea life as we know it is at risk. Other effects will likely make matters worse: There are indications suggesting that climate change could lead to the destabilization of (solid) methane hydrates in the oceans and to the release huge amounts of methane gas - a much more effective accelerator of climate change than CO2 - into the atmosphere thus accelerating climate change even more. Also, melting glaciers and polar ice reflect less sun, again speeding up the warming of our planet.
So, we know.... we know (!) that our planet is heating up because we emit far too much CO2 and other gases with similar effects. And we know (!) it will lead to the destruction of our nature, to global conflicts and ultimately to our own extinction. Also - just to remind you - there ain't nowhere else to go. I know, Elon Musk wants to go to mars, but its not particularly pretty there either, and any further destination would require interstellar travel, and we are not even close to that.
So Earth it is. And because we don't want to stop flying around, stop using our gas guzzling cars, stop producing energy with coal plants, stop eating meat - in short - because we don't want to change anything in our behavior on a personal or global level - no carbon tax, nothing - we will all die or live our lives in misery, hiding from war and carving for a sip of drinkable water.
The sun produces more energy on our planet in a day than we would need in a year. Still we prefer to burn up fossils like there is no tomorrow. Well, if we continue like that, looks like there won't be a tomorrow.