Alone in an indifferent universe, the choice is ours alone. Can we, will we survive?
It is possible humanity will be wiped out and disappear as if it had never existed. In that case everything we have no loved, hated, thought, felt, remembered, hoped-for, dreamed or built will be lost forever. Our very existence will have become meaningless.
How could this happen?
The earth was formed 4 1/2 billion years ago. for at least 2 billion years it has been capable of supporting life. 50,000 years ago something crawled out of the tide pools and became us. 10,000 years of recorded history has brought us to our present state and here's datapoint:
25 years. 25 years out of 50,000… 25 years out of 2 billion.
In 1945 we created the atomic bomb. In 1969 we landed on the moon. 25 years . The razors edge. Within 25 years we gained the ability to wipe ourselves out and the ability to move into a new frontier; to spread humanity throughout the solar system and beyond, to hedge our bet against catastrophe, and to develop a sustainable planet.
The greatest engine of climate change is population explosion.
There are now 7 1/2 billion people on the planet, heading toward 10 billion by mid century and 15 billion by 2100. The carrying capacity of the planet has been estimated 5 1/2 billion people max. As the population swells and people desire a better standard of living, the requirement for energy explodes. According to our scientists there are no earthly technologies now online or capable of coming online in time that can provide the energy that we will need.
The energy that we now use is finite and laid down over 4 1/2 billion years. In a few hundred years we have used up more than half. One way or another this is last century for fossil fuel. But in burning the fuel, we have known for over 100 years, that We are changing the climate.
With sea level rise, Bangladesh is underwater. 45 million Muslims are forced off their land. They are forced into the land of their neighbors, Hindu India. No nation can quickly support 45 million aliens, but all nations with a seashore will face this prospect. Conflicts will likely lead to a nuclear exchange. Nuclear bombs respect no borders. Clouds will drift into neighboring lands killing their population and then will be carried throughout the world. This will trigger the doomsday machines or dead hands Computer programs built by brushing an American in the Cold War which cents a level of radiation concurrent with an attack on the homeland in which they are programmed to launch all nuclear missiles.
These toxic clouds will be composed of radioactive isotopes with various half lives; the amount time radiation diminishes by one half. The half life of plutonium is 20,000 years. If there is enough plutonium on the surface of the earth and in the clouds to kill you 10,000 times, in 20,000 years it would only kill you 5000 times and 40,000 years it would only kill you 2500 times and so on.
Nuclear war will make the earth uninhabitable for mammals for several million years. In 2 billion years it's possible this happened again and again and again.
Other ways to reduce the population are pandemics spreading rapidly in close-packed populations, super volcanoes and civilization-killing asteroidal impacts. The good way of reducing the population is by human intellect; by spreading humanity into the new solar system, raising the average wealth of the entire earthly population, so that poor people don’t need to have a large number of children to support them in their old age.
And then there is opening a new frontier.
A new frontier