I hate to add more grimness to the picture you’ve painted, but ocean acidification will leave our seas with no fish. The sixth great extinction, the first even caused by human activity, is now well underway. We mammals naturally worry about other large fauna, but insect populations are going extinct at something like 10,000 times the normal background rate. We don’t even know how rapidly bacterial life, plankton, fungi, and krill are disappearing,. What we do know is that these tiny critters and plants are the foundation upon which Earth’s entire food chain stands — or falls. I am not hopeful that anything other than extremophiles will survive into the 22nd century.