These 4 charts explain why the stakes are so high at the U.N. climate summit

Leaders from around the world are gathering in Glasgow, Scotland, to hammer out new pledges to fight climate change. The stakes are high. Scientists warn that heat-trapping emissions must fall dramatically by 2030. Otherwise, the world faces more extreme hurricanes, floods and droughts, likely displacing millions of people. Still, negotiations at the COP26 meeting are expected to be tough. Here are four reasons why.

#1 The world is not on track to avoid extreme climate change

Countries have already made pledges to cut their greenhouse gas emissions by moving away from burning...