Sea level rise will not erase Manhattan. Only some significant geological event (or extra-terrestrial impact) could conceivably erase Manhattan to the degree t

Sea level rise will not erase Manhattan. Only some significant geological event (or extra-terrestrial impact) could conceivably erase Manhattan to the degree that it would not be easily discoverable (or partially visible) to future generations. Documenting and distributing one's history is not especially difficult to do with today's technology. The easiest solution I can think of would be to scatter mineral etched documentation into orbit around the planet, along with some very long lasting vertical markers on the land. But really, one most ask what the point of documenting anything is if all humanity is expected to be eliminated. It is likely that our waste will document our existence more accurately that our intentional efforts, and the later (more advanced) visitors will recognize our primitive collective mentality, choices, and demise.