As a warming Earth simmered into worrisome new territory this week, scientists said the unofficial records being set for average planetary temperature were a clear sign of how pollutants released by humans are warming their environment. But the heat is also just one way the planet is telling us something is gravely wrong, they said. “Heat sets the pace of our climate in so many ways ... it’s never just the heat,” said Kim Cobb, a climate scientist at Brown University. Dying coral reefs, more intense Nor’easters and the wildfire smoke that has choked much of North America this summer...