Shocking ‘Airpocalypse’ Timelapse of Smog Rolling Into Beijing

This striking timelapse is rapidly going viral online. The video captures what appears to be a thick bank of smog rolling into Beijing yesterday—20 minutes compressed into 12 shocking seconds of timelapse footage.

The timelaspe was captured and posted online by British expat Chas Pope, who describes the scene as “a bank of AQI400+ smog arriving in Beijing within the space of 20 minutes.” AQI stands for Air Quality Index, an official air quality rating system that ranges from 0 (good quality, pure air) to 500 (hazardous air quality). Pope claims this smog is up in the 400+ region on the AQI; anything over 300 should trigger widespread health warnings.

Beijing has been experiencing particularly horrible quality air recently, with the city issuing a “red alert” on December 16th, an emergency level that requires all older, high-emissions motor vehicles to stay off the road and schools to close, according to the New York Times. “Hundreds of flights were canceled and highways were shut down because of low visibility,” writes the Times. Beijing experienced similar conditions Tuesday.

But no warning, no matter how dire sounding, has managed to capture the severity of the situation as well as Pope’s 12-second timelapse. The video’s title, “Beijing Airpocalypse Arrival,” is not hyperbole.