Dear Tom,
I remember the Paris Climate Agreement is 2015 in which countries agreed to reduce carbon dioxide emissions. How has that been going?
Axel Miller

Dear Axel,
It has not been going well. Carbon dioxide emissions were flat in 2014, 2015 and 2016 but rose in 2017. Based on present trends, the Earth will warm about 5.8 degrees above pre-industrial levels by 2100. This is well above the goal of a 3.6 degree rise set in the Paris accord. A United Nations report states that worldwide carbon dioxide emissions would have to be reduced by 25 percent by 2030. In order to keep temperature rises under 1.5 degrees, which is what is believed to be necessary to keep the planet relatively cool, carbon dioxide emissions will need to be 55 percent lower by 2030.