We all know about climate change now, and we all know that our animal and plant species are disappearing fast. But we don’t yet know how this story will end. The 2020s will decide that. This is the make-or-break decade. By New Year’s Day 2030, everyone will know whether we’ve failed and are accelerating towards collapse of the global ecosystem, or whether we’ve succeeded in switching onto a new track to a sustainable future. While this may not matter much to the older generation, it’s vitally important for the younger generation with most of our lives ahead of us.