[jarnagin]

It’s tempting to believe that climate change just means that some places will get hotter or colder, or that species will move north or south, upslope or downslope, but the reality is that we don’t really know. Much of the work coming out of ecological niche theory shows that ecosystems have many emergent properties and can’t simply be studied at the level of an individual species because those species wouldn’t survive without their symbiotic relationships [1]. What is true at the species level, however, is that each species has a unique and oftentimes non-overlapping adaptation to whatever environment it’s in relative to its peers. That means that as the climate shifts, some species will go north or south, or upslope or downslope, and others will behave differently. The consequence is that many ecosystems will literally be pulled apart, and species which lose their symbiotic relationships will have to either adapt over a short time span or go extinct. Assuming the climate stabilizes, it will take time, probably much longer than humans are comfortable with, for things to reconfigure.

[1] https://www.pnas.org/content/106/Supplement_2/19729

[eloff]

Yes, I don't think that's surprising or seriously contested. Rapid change means species will have to adapt or die, and many will perish. It's not the first time that's happened on Earth, but it is the first time since the end of the last ice age. It's a terrible slow-motion train wreck that seems nearly unstoppable. Humans too will have to adapt, and some number of us could well perish also.

Longer-term I have the controversial opinion that it's a good thing (downvotes incoming!), but that could just be my tendency to look for the silver lining. Being Canadian and knowing that my entire country was buried under kilometres of ice and then scraped clean to bedrock 12,000 years ago, I feel that's a more dangerous long-term risk than global warming and rising oceans. Think of how much food we grow in northern and southern latitudes. That process would maybe have begun in about 1500 years, and one could imagine that stopping that might involve crazy things like digging up buried hydrocarbons and burning it to add CO2 to the atmosphere, or spraying dark pigment over ice and snow to reduce the albedo (rename Greenland to Greyland anyone?)

We've fucked things up pretty badly for the next thousand or more years, there will be mass extincions, mass migrations, maybe even famines and wars. But we also dodged an icy bullet for who knows how long. I take some comfort in that.