A landmark report from the United Nations' scientific panel on climate change paints a far more dire picture of the immediate consequences of climate change than previously thought and says that avoiding the damage requires transforming the world economy at a speed and scale that has "no documented historic precedent."
Basically, if the current gas emissions level stays the same (not even talking about if it's worse), the atmosphere will warm up by 2.7 degrees Fahrenheit and "50 million people who will be exposed to the effects of increased coastal flooding".
The authors found that if greenhouse gas emissions continue at the current rate, the atmosphere will warm up by as much as 2.7 degrees Fahrenheit (1.5 degrees Celsius) above preindustrial levels by 2040, inundating coastlines and intensifying droughts and poverty.
https://www.nytimes.com/2018/10/07/climate/ipcc-climate-report-2040.html
I cannot understand why so many people just don't care.