One of my favorite sources of visuals for this blog is XKCD.com. “A webcomic of romance, sarcasm, math, and language.” It is created by Randall Munroe, who is an interesting guy.
I’ve used his strips roughly monthly. “This work is licensed under a Creative Commons Attribution-NonCommercial 2.5 License. This means that you are free to copy and reuse any of my drawings (noncommercially) as long as you tell people where they’re from.”
The piece Earth Temperature Timeline (https://xkcd.com/1732/) appeared in January 2022, but I thought it was a good fit for Earth Day.