There people, including those elected to office down in the USA , that believe man co-existed with Dinosaurs.Others believe the Earth was created in 4000 BC so there could not have been “3 Million years ago”. Others feel that The Baby Jesus will come down and save everyone so why worry.
Then there that common human trait of only being able to look a few years down the road. This leads to all manner of risky behaviour such as diet , sports engaged in such as those atheletes hitting their 40s and dealing with the after effects of concussions and blown out knees or the overweight person now having to deal with a failed heart , or those that never saw themselves retiring or envisioned themselves at 80 when they were in their 20’s.
It pretty hard to gain enough critical mass to get this large swathe of people to think of these things that are going to happen 50 years down the road or even 20 for that matter. The way I try and motivate myself and others is to recognize the IMMEDIATE harm such as all of the animals going extinct or the forests being destroyed for the sake of tarsands.
I can talk to relatives in Alberta who will simply stare at me blankly when I speak of warming and the effects 50 years from now , but as soon as I show them pictures of the devastation of our forests or point out that animal species (such as woodland Caribou) near extinction they begin to wake up. That said even that will not sway those Religious nuts I exampled in my first paragraph.