|Before and during|
According to readings, from the US Embassy in Beijing, air quality particulate pollution readings have reached up into the seven hundreds. The normal scale maxes out at five hundred. Literally meaning that pollution levels are off the chart.
Above, the picture you see shows Beijing on a regular day, sometime in 2012, to the left. On the right you see the same angle taken during this last week.
Below are two photos released by NASA. They show the same region of China, but on two different days. In the top picture we see a view, from space, of January 3, while the bottom shows January 14. According to NASA the particulate pollution readings was three hundred and forty-one, when the second picture was taken.