The World Health Organization (WHO) estimates that human-caused climate change is already responsible for 150,000 deaths annually. If we continue our current trajectories of "business as usual" as our response to climate change, the WHO expects that between 2030 and 2050 climate change will cause approximately 250,000 additional deaths per year. According to the WHO, the yearly death rate will include, "38 000 due to heat exposure in elderly people, 48 000 due to diarrhoea, 60 000 due to malaria, and 95 000 due to childhood under nutrition.
Once "tipping points" occur, non-linear changes will emerge, and the death toll will be much higher.
As author David Ray Griffin demonstrates in his book, Unprecedented: Can Civilization Survive The CO2 Crisis?, we are facing a constellation of unprecedented, intersecting threats that are leading humanity to increasingly severe catastrophes, and possibly even extinction.
The unprecedented, lethal threats identified by Griffin are these:
Droughts and wild fires
Sea level rise
Fresh water shortage
A closer examination of just one of these threats shows how they are inter-related: