Surprising discovery: Smog may help slow down global warming temporarily

LOS ANGELES (KABC) -- Tourists come to Los Angeles to take in the sights of the downtown skyline and the iconic Hollywood sign, but what they don't expect to see is the traffic and smog.

The particulates found in air pollution may have kept temperatures lower, according to scientists at NASA's Jet Propulsion Laboratory in Pasadena.

"They either reflect sunlight back to space or they absorb sunlight from the atmosphere. Both effects prevent sunlight from getting to the surface of the Earth," said Mika Tosca, a researcher at the Jet Propulsion Laboratory.

Tosca studied satellite data and temperatures in the southeastern United States going back to the 19th century. She says temperatures there have risen in the last 15 years as the amount of air pollution has been reduced.

The findings show that once the pollution was removed, it sped up global warming in the south faster than other parts of the U.S. and the world.