This is Beijing, one picture BEFORE a parade and after.. People were so excited to finally see a blue sky in the city, they whipped out cameras to capture the moment.. (http://www.cnn.com/2015/09/04/asia/china-beijing-blue-sky-disappears-after-military-parade/)
The CNN article linked doesn’t mention much about this, but I wonder if it was also utilized by China: Manipulating weather. 

Back in 2008 they proved they knew something, with their intent on making sure it would not rain during the Olympic games.





But have they gotten as good as making there be some blue skies in an otherwise hopeless and polluted city?