A historic outbreak of wildfires across Northern California left a massive layer of smoke draped over the San Francisco Bay Area, turning skies into an eerie dark orange haze and covering cars, yards and homes with layers of ash. Climate experts believe this is part of California’s ‘new normal.’ The wildfires in the state have already burned through over 2.5 million acres this year. The sun’s rays struggled to penetrate the smoke, and at 10:45 a.m., it looked as if it were dawn. As of now, the fires have also led to at least 11 deaths since last month.

Obama himself took to Twitter to share these images along with a message about climate change. “The fires across the West Coast are just the latest examples of the very real ways our changing climate is changing our communities. Protecting our planet is on the ballot. Vote like your life depends on it because it does,” he tweeted.

In San Francisco, people walked or rode bikes along the Embarcadero, their tiny headlamps emanating a blue glow contrasting with the warmer colours surrounding them and reflecting on the water near the Bay Bridge. Many were out with phones or cameras, documenting the unusual natural phenomenon.

What caused the sky to turn orange?

Toxic wildfire smoke in the atmosphere caused the San Francisco skies to turn orange. “Extremely dense & tall smoke plumes from numerous large wildfires, some of which have been generating nocturnal pyrocumulonimbus clouds (‘fire thunderstorms), are almost completely blocking out the sun across some portions of Northern California this morning,” UCLA climate scientist Daniel Swain shared on Twitter.

What is the air quality like now?

Surprisingly, despite the darkened sky and showers of ash, the air quality index in San Francisco did not reach unhealthy levels. Fog from the Pacific Ocean, wedged between the smoke and the ground, acted as a filter, as per reports.

The effect was most pronounced in San Francisco, where bright red-coloured photos of the city’s iconic landmarks, Lombard Street, Embarcadero, Coit Tower, Golden Gate Bridge, and Bay Bridge, flooded social media, complete with explanations of “no filter”.