If you accept the science of climate change, you realize how bad things will get very soon and how mind-blowingly, unaffordably expensive mitigation and adaptation will be.
The Ministry for the Future is a thought experiment, a sketch of a blueprint for how we might salvage civilization and a habitable biosphere, therefore worth reading for that alone.
There's a lot of science, a lot of politics and much more economics than in your average speculative fiction, and the variety of voices may be challenging for linear readers, but it's a solid, mesmerizing book.
Can humanity overcome its divisions, or be made to when push comes to shove? The Ministry for the Future parlays small gains into larger ones. You should read it.