If the world chose to ignore and do nothing about climate change.In your opinion how many years would the earth have left before it couldn't support human life?

648,791 x 88,252, carry 9,690 =...erm…=...lots!!

I’d guess one hundred years for big storms and major inconveniences.

Two hundred years for it to be too much for us to handle.

It’d have to get pretty fucking bad to get to extinction-level. We’re a resilient virus. There are people willingly surviving in the Sahara Desert and Antarctica.

I give mankind a maximum of 250 years. But I don’t think climate change will do us in, it will be those increasingly antibiotic resistant superbugs. Once antibiotics have no more lifesaving effect, the median age will fall (for men) from 76.3 to less than 30 years.

We have been around long enough to see plenty of climate change already, at worst it’ll bottlneck us again and we’ll have some new cool traits to use. We don’t get to choose if the climate changes or not. Slow it down or speed it up…maybe. The only provable climate change fact is we have increased C02, everything else is conjecture. We should do something about that but not haphazardly as some would have us do.

15 years

It will not be much problem. Global warming won’t kill humanity. We’ll adapt and move places where we can survive well. In any case, even if a lot of land is underwater, there will be a lot more land that becomes prime farmland in Canad and Siberia, for example, both of which are very big, unpopulated places. And who knows what will happen to rain patterns. Perhaps the middle of Australia will become lush.

Bill Gates is supporting research into a technical solution to global warming, and I have no doubt that one will be found—or rather, many different solutions. But I hope they aren’t found too soon. I like the movement towards renewable energy sources, and if we find a technical solution to global warming, we’ll probably get lazy again, and go back to burning hydrocarbons, which have grown so cheap and plentiful, when everyone was saying they were about to run out. Our ability to project into the long term future is notoriously underwhelming.

I hope it is clear I believe that global warming is occurring. I think we should be planning on how to relocate populations in a safe way. The current refugee crisis in Syria is showing us what we will have to face, only much bigger. It is inevitable that many lands will get swamped and many of their people will have to move (although others will raise their homes on stilts). We need to plan for those movements now. But we won’t. Everyone is still thinking that global warming is avoidable. It ain’t. It’s already here. But even those who believe in it are acting as if we can still change that fact, so our attention is on the wrong thing.

I’m not sure how global warming became an Extinction Level Event. Over the history of the earth there have been periods of warmth and cold. The warm periods are marked with abundant plant and animal life while the cold periods are marked with death and destruction with little life. My greatest fear is that the warming zealots will come up with some hair-brained scheme to reverse the cycle and throw us into another cooling period, maybe the next ice age. That would be an extinction level event. Until then we can worry about Nuclear Winter or some such man made event. Humans will survive just fine until the temperatures begin to drop.

@Jaxk: What is going to happen is that the storms that we’ve been experiencing are going to get worse.