Ethan Siegel in Forbes:
Like most people on Earth, Greta Thunberg is not a climate scientist. She has no formal scientific training of any type, nor does she possess any expert-level knowledge or expert-level skills in this regime. She has never worked on the problems or puzzles facing environmental scientists, atmospheric scientists, geophysicists, solar physicists, climatologists, meteorologists, or Earth scientists.
Like most of us, she is an ordinary citizen of the world: with strong beliefs, opinions, and political inclinations. But unlike most of us, Greta has shown a willingness to do what most of us refuse to do. Her starting point for how to move forward in the world is to begin from a position of scientific consensus. While most of us prefer to be given the facts and trust that we, intelligent as we are, can figure it out for ourselves, Greta recognizes the unparalleled value that scientific expertise brings to our world.