I think the species has much, much longer, but our civilization?... we're pretty much dooming that. In a few decades the options will be, "scientific miracle" or, "Slow decline".
That assumes we don't blow up as a species form the conflict which arises as the climate shifts... something we're already seeing a bit of in North Africa for example.
Civilization will be redefined. We are moving to a mass participation, hive-mind, internationalized structure rather than a series traditional country or culture-walled hierarchies with inward-looking tradition.
This is not all bad, but IMHO we have definitely already experienced a distinct loss of clarity of expression across the western world (the letter-writing tradition and books = properly constructed line of reasoning, structured writing, considered communication -> emails and emoji = short, emotional reactions, unstructured/unsupported opine, ill-considered). On the flip side, everyone can communicate and a lot of pedantic grammar laws are becoming irrelevancies. People genuinely care more about being understood than pedantry, and that's a good thing IMHO. As for food/water/environment/waste-management/freedom, on the whole our political systems (exception: China) are not able to effectively reason on those timeframes, and find it easier to pass the blame internationally. We all know where that is leading.
You're talking more about culture, I'm talking about banging the rocks together levels of absolute downfall. I think your view is probably the more optimistic one.
I think it's between "slow decline" and "precipitous collapse".
Nuclear war, sudden energy shortage, food stores wiped out, radiation leak, EMP terrorist attack, Electric grid sabotage, Solar flare EMP, Magnetic pole reversal, sudden economic collapse, sudden ecosystem collapse.
We'd be lucky to "slowly" lose our civilisation to climate change...
Personally I have sworn off the car, and my only significant consumption on this planet is my computer, and my aeroplane journeys. Otherwise it's mostly just food, water and train rides. No idea how else I can contribute...
