Alrighty, @Milano! You're next! :)
So Meadow Robbins (cool name, first off!). I'll be honest, I'm having a little bit of trouble grasping this character. I think that, over all, you need to be a little bit more descriptive with her non-physical traits, and maybe give her some more dimensions. But I'll elaborate on that in my full critique, so just keep that in the back of your mind!
Overview looks perfectly good, no problems there (I find there rarely are anyways).
Height/weight ratio checks out. Wow, that's one flowery description for her appearance! I can appreciate a good simile, though. The line "…like she came with the earth, not to the earth" gave me the first inklings that maybe she isn't from this planet, so nice subtle hinting there! On that note though, I think you are a little on the nose with all of your descriptions. I immediately got the impression that she was an earthy, tree-hugger type (not mad at that, I totally am too!), and while it can be cool to have that manifest in her appearance, make sure that isn't her only trait and the only thing you are working her character around. It kind of seems to be at the moment.
And that takes us to her personality. I'll be frank with you, it always annoys me a when people say they "want to go back in time to stop climate change". I am an ecology major, so the environment and wildlife preservation are insanely important to me! Trust me, I'm basically dead set on becoming a riverbank and wildlife restorationist in the future; global warming and climate change are not just as simple fixes as changing the past. One would have to basically change thousands of aspects about all of human history since the development of agriculture to even hope for a world without global warming. Even in a world where time travel does exist, the changes that would have to happen to stop global warming would have other devastating effects on the future, and it is pretty foolish to ignore that. I think if you are dead set on having this as her motivation, you should take all of this into consideration, and please, for the love of god, make sure your science is correct!!! The way your story sounds right now, it leans towards sci-fi, and I promise you sci-fi critics will absolutely tear you a new one if you get the science wrong. (I am always here as a resource, though, if you need to fact check. Scientific research is hard work, and for someone who cares more about the actual writing its probably pretty daunting, so don't be afraid to ask me questions! :) ).
I promise, I'm not trying to be mean, I just want to give you a thorough and honest critique here. Aside from that, though, I do quite like her personality! Maybe expand on her flaws and describe the whole section a bit more, but it's a great start!
Again, I need more when it comes to her history, but it's interesting. I like the idea of someone not born on earth being so devoted to its health! Super neat! Maybe just explore the "why"s of her character more; why does she care so much about the earth when its not even her birth home? Why does she think that time-travel can help her?
Oh! I actually have a great resource for you! There is a whole sub-genre of sci-fi called ecofiction, that basically focuses on the impacts of climate change. A lot of it has to do with the aftermath of climate change and things like that, and this plot seems to fall within that category. It is pretty pessimistic where your story sounds like it has an optimistic tone, but I think that you could really benefit from reading some ecofiction works. The most popular example is "The Grapes of Wrath" by John Steinbeck, but that's a pretty advanced work and I don't know how old you are to accurately recommend literature to you. Send me a pm if you are at all interested in some recs!
So, I think you could expand a lot more on Meadow, but she has a good basis and this story seems promising! I'm sorry if I went off a bit hard on you, and keep it up! :)