With our eyes we can see landfills, plastic pollution on the beach, litter floating on the water, and it all makes immediate sense to our senses. 

But, changing the sky with invisible gases? We actually can, and we have done that dramatically. 

Check this interesting article with clear pictures about climate change: https://globalecoguy.org/the-three-most-important-graphs-in-climate-change-e64d3f4ed76?fbclid=IwAR36YyB3Ca0GkySI_ohS0szrqH98hOtA1OYMSe5GLV8HodOvSjcEE7tvPNc&gi=c7d7660e3dc5