The science behind global warming, including environmental consequences has been known for a long time. The technical details are provided by world respected sources that are easy to find on the internet. What's missing is personal advocacy. Dean (Racho) presents a really good mixture of the two in a Youtube, but mistakenly thought that the scientist was refuting rather than supporting climate change.
Greta does a better job of personal advocacy, deferring to experts for the science part--especially experts in areas that have studied adverse consequences.
Meanwhile, Donald tweets: