I would put the sun and volcanos at the top of the list, but then I’m not a climate scientist.
You nailed it morphing! Sun’s effect dwarfs any human factors, but if there is a second influence, volcanic ash would be a strong candidate. The Iceland volcanoes spilled thousands if not millions of times as much particulate matter into the atmosphere in a single year as all of human activity ever did. Media ignoring that, of course.