Beijing’s signature smoggy atmosphere recently dissipated, albeit briefly, to reveal an unfamiliar beautiful blue sky. Two weeks ago, Chinese officials banned use of five million cars to make way for the largest parade in the city’s history. The usually pollution-ridden city enjoyed two blissful weeks of clear blue skies thanks to the car ban, but sadly the smoggy skies returned last Friday as the usual traffic resumed.

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For Beijing’s largest military parade that marked the 70th anniversary of Japan’s defeat in World War II, Chinese authorities decided to set the stage- with an extraordinary clear blue day. The act took weeks of preparation, which involved seriously cutting down on the city’s massive pollutants that normally cause Beijing to be smoggy and grey. Officials began temporarily shutting down hundreds of pollution-producing factories across the region in order to help “clear the air.”

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In addition to the shut-down of factories, the city banned another major cause of pollution – the nearly five million cars that regularly jam Beijing streets and release endless CO2 emissions. These actions produced the desired clear blue day, revealing a view of Beijing that locals, and the world, had not thought possible. The air quality index, usually at dangerous levels, sunk to a desirable 17 out of 500. The gorgeous blue was nicknamed “parade blue” on the internet, marking the city’s rarity.

Although locals enjoyed clear blue skies on the morning of the parade, they were dismayed to awaken to the familiar muggy gray on Friday, as regular traffic and factories were reopened. Sadly, the gray clouds resettled into the cityscape, and the parade blue day will remain a bittersweet faded memory.