Careers in climate / sustainability

Hi folks -

I was wondering if people here might know of companies that are doing good stuff in sustainability / climate tech etc. I don't have any experience here but I do feel that's one of the key problems facing humanity and I'm thinking I might feel happier if I feel my work is actually meaningful lol. Open to using my free time to study / upskill in this area.

I have looked up Terra.do as well but their flagship course is too expensive and I'm not sure how useful it is.

(Currently in a strat ops role)

So does anyone have suggestions on companies / courses that can help?