They will. However, areas, where almost no one lives today, will be inhabitable instead. There's plenty of barely inhabited space on Earth. That will be a gian

They will. However, areas, where almost no one lives today, will be inhabitable instead. There's plenty of barely inhabited space on Earth. That will be a giant migration crisis, on an unprecedented scale, sure. Maybe even a world war. Nothing good, not in slightest. Something best avoided at all costs. Yet, the point is, if this won't be avoided - humanity as a whole is still not in danger. We're not going extinct if Earth will warm up. The world will change drastically, many millions will die, ecosystems will be shattered - but H.sapiens aren't going to disappear as a species.