“People Don’t Realize This” about Climate Change, Elon Musk Says

Plenty of people have sounded the carbon emissions alarm over the years. In his recent-ish election season talk with Donald Trump, Elon Musk unexpectedly joined their ranks. Unexpected not because he supports action on climate change -- we've known this for a long time -- but because he claimed that rising carbon dioxide levels will make it uncomfortable to breathe, and give us headaches and nausea. Really?