Unfortunately the pollution gods seem to have taken it as a challenge. PM2.5 AQI levels climbed and climbed across the east coast of China, covering the cities in a gray shroud of smog. The AQI levels in Shanghai crossed 500 for the first time in recorded history, to a level literally off the charts.
Pollution levels are color-coded by hazard level.
That's showing over a day and a half at the highest level.
Related: China's suffocating blanket of smog even visible from space