Currently reading Ministry for the Future, which in some ways is a very optimistic book, but is still quite grim. Also, I'm thinking perhaps next time I'm tempted to read a book with climate change as the subject, I'll wait until winter to do it, rather than in the summer when the described scenes are a bit too easy to imagine by simply stepping outside.

Read the mars trilogy and Rice and Salt as well. I like his optimism in humans' ability to actually make radical political change. I suppose this is what I mean by his being both optimistic and grim -- severe outcomes aren't avoided in his books, but in the end societies do change before the absolute worst comes to pass. A "hard optimism" I suppose, which I find valuable.