The deserts of China are expanding.

And that means unbelievable dust storms. These storms used to happen every seven or eight years, now it's an annual occurrence. The increased frequency is tied to the rapid urbanization of northern China, deforestation and climate change. Not only do the storms reduce visibility in cities like Beijing, they also threaten the health of millions of people. The current storms led to the cancellation of flights and caused pollution in northern China to soar. 

Beijing’s air-quality index hit a level of 623 on Thursday; the United States rates readings above 200 as “very unhealthy” and 301 to 500 as “hazardous.” The government has spent billions of dollars to plant forests to stop the creeping desertification.

Here's a before-and-after shot: