I'm writing a sci-fi story in which all life in most of the N. Hemisphere instantly ceases to exhist. How it happens and where all that carbon goes is part of the sci-fi (assume it's just gone), but what I'm curious about is what would likely happen to the planet in things such as...
... global climate? (Ice age or warming?)
... evolution of plants and animals?
This is primarily over the next 250 years and assuming that a) ocean life was mostly preserved and b) humans are out of the picture.
I'm also curious what effects might play a role in the gradual recovery of the global balance, given that all life in the Southern Hemisphere survives the initial catastrophe. What would the Earth look like in 250 years?
Google: I followed a few leads to reading about the impact of supervolcanos on climate, but it looks like most of their effects come from Sulfur, which wouldn't be the case here. This might be more akin to a meteor impact, but I'd still love to hear other ideas. There is also a study that says it takes a forest 140-200 years to recover 40-80% of its growth, but that's assuming that the devastation didn't take up half the planet, so.... *shrugs*