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.

"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 are among the many other signals of climate distress. "The increasing heating of our planet caused by fossil fuel use is not unexpected, but it is dangerous for us humans and for the ecosystems we depend on. We need to stop it, fast," said Stefan Rahmstorf of the Potsdam Institute for Climate Impact Research.

Newly published data from the Copernicus Climate Change Service documented "Exceptionally warm" ocean temperatures in the North Atlantic with "Extreme" marine heat waves near Ireland, the U.K., and in the Baltic Sea. Several rounds of wildfire smoke originating from northern Canada brought dangerous air quality levels to eastern North America.

The high levels of wildfire smoke have become familiar on the West Coast, but scientists say that climate change will make wildfires and smoke more likely and intense and that the East Coast will see more of it. The current El Nino - a period of warming Pacific Ocean waters - formed a month or two earlier than usual, replacing a La Nina that, with its cooling of Pacific waters, served as a damper on global temperatures.

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