It isn't just humans, the but the plants and animals that will be wiped out. Predictions include coral reefs dying out, severely reducing aquatic life habitation. There are more severe weather patterns with hurricanes and tornados. Last winter, the Gulf Stream failed temporarily as it was overpowered by the Eastern Siberian weather, plunging snow across Europe. Areas will be flooded and others experiencing severe droughts leading to desertification.

Humans as a species won't be wiped out, but a couple of degrees has a massive impact across the planet.