NASA and a crew of university scientists have concluded that about 64 million tons of dust, pollution and other airborne particles from Asia are transported by air to North America.

That's almost as much as the 69 million tons that is believed to be generated annually within North America from natural sources, industry and vehicles.

Dust accounts for most - 88 percent - of the particles carried over from Asia, according to a study published in the journal Science this month.

The study is the first measurement-based analysis of airborne particles. Scientists were able to get a three-dimensional view of the atmosphere by using satellites.

The map with this blog depicts airflows in April 2010. Most of the dust comes from spring dust storms originating in the Taklamakan Desert in central China.

Tracking aerosals and quantifying their impact on the earth's climate is one of the most difficult aspects of understanding climate change, according to NASA.

North America also gets dust and pollutants from the Mideast and Africa, according to NASA.

Source: NASA/Earth Observatory