A new report from the United Nations is sounding a dire alarm on climate change, warning that temperatures will rise more than 1.5 C (2.7 F) if world leaders don’t act immediately to reduce carbon emissions.

The report by scientists with the Intergovernmental Panel on Climate Change describes an apocalyptic scene of wildfires, sea-level rise, extreme weather, coral reef extinction and massive food shortages as early as 2040 if global warming is allowed to continue at its current rate. With the help of technology, some of which hasn’t been invented, the world can become carbon-neutral and hold the temperature rise to 1.5 degrees Celsius, the report said.

“Limiting…