In this scenario, the oceans would boil away into space, as our atmosphere disintegrated into nothing, allowing the harmful radiation of the sun to literally devour us all, before we all perished in vacuum.
If an occurrence such as an Extinction Level Event were to take place, there is not much we can do to remedy our situation, aside from leaving the earth, or finding some way of terraforming what was lost. If an atmosphere is stripped away, how can it be replaced? Planetary habitability is an important factor to be considered in such an endeavor, as is the establishment of ecopoiesis, a necessary part of any planetary body suitable for human survival. Provided that these steps could be satisfactorily accomplished, our chances of species survival could be greatly enhanced.
To truly ensure our survival as a species, we would need to find a way to spread our seed to other habitable planets in far off solar systems. In order for space travel to become a reality, cost would have to be ignored as a factor. Tremendous resources would have to be allocated in order to build a mode of travel significant enough to carry even a few humans over a very large distance. A self-contained biosphere might be the ticket, one that could stand the test of time, the vacuum of space, and the assault of micrometeorites, radiation of all kinds, and prevailing events. Every part of such a transport mode would have to be engineered to last. A means of safely shuttling passengers from space to a final destination would also be necessary. We have proven that the best chances of survival depend on our willingness to colonize, something we have not done for centuries.
But, with odds such as those I have discussed, the chances are still slim, for we are a fragile race of beings. Perhaps a point of our survival might be the ability to change our very physical makeup, perhaps evolve (or even devolve) into a lifeform capable of living through practically any catastrophic event.
More to come…