In 2019, the Sierra Club endorsed Greta Thunberg for the Nobel Peace Prize. Michael Brune's post in this regard is located at https://www.sierraclub.org/michael-brune/2019/04/greta-thunberg-nobel-peace-prize-earth-day. Here is an excerpt from his article:

"Awarding Greta Thunberg the Nobel Peace Prize would align with the award’s tradition of recognizing leaders who have the vision to confront global crises in spite of seemingly insurmountable odds. Thunberg is a leader of today and tomorrow who has made her voice heard clearly around the world and refused to accept that tragedy is inevitable. Her courage and determination have helped build a global movement. And yet, she is only in high school."

Here is a link to a podcast in which she describes her efforts in 2019, which entailed everything from speaking to the United Nations General Assembly to traveling across America and Canada and back to Europe, working hard to communicate the urgency of addressing climate change immediately. It's a truly impressive body of work. Below the link to the podcast is a link to the text transcript.

Greta Thunberg: Humanity has not yet failed - Sommar & Vinter i P1 | Podcast on Spotify

Transcript:
https://time.com/5863684/greta-thunberg-diary-climate-crisis/