@ErgoVoid I'm sorry you are living in an environment so separated from nature.
I have been fortunate to have enjoyed fairly easy access to nature throughout most of my life thus far. I did try to live in a big city once and could not hack it because there was just too much concrete everywhere. I hated it! So I do know where you're coming from on that front.
I feel your stress about anthropogenic climate change too, although I'm not as pessimistic as you on that front. Yes, it's bad, and it will likely get worse before it gets better. We've got a rocky road ahead of us still. But a lot of people want to do better. A lot of people are calling on their governments to do better. And governments are starting to listen. I think we'll get there--hopefully before it's too late for our species, but certainly before it's too late for nature in general. (Humans are far from the hardiest species on Earth. Plenty of species will survive our tenure on this planet.)
I think it's great that you can visualize nature while meditating, in spite of your circumstances! I know it's not the same as being outside in it, but it can still help. I would like to share with you a couple of YouTube playlists I've made. My
Monday Meditations list is a series of 1-5 minute videos I shot of natural places near where I live now. It's far from professional footage: just me with a handheld point and shoot camera (or a GoPro strapped to my forehead in the case of the paddling videos). I made the videos so I (and others) could meditate with nature (or at least audio and visuals of it) when I/we am/are not able to physically get outside and into a natural environment at the time. (Except for the final video in the list, which I didn't have anything to do with.
Unique nature vs nurture essay samples help me understand the role of environment for our development. The essays provide great ideas about nature vs nurture. A couple of those were shot in my parents' living room, and the only audio is my mother talking (and me at one point), but most were shot outdoors and feature bird (and other creatures') songs. I hope some of these can offer you a little nature pick-me-up when you need it most.