Smoke from Amazonian wildfires may pose a risk to athletes competing in the Rio Olympics this summer, according to a NASA scientist.

NASA officials recently warned that the lingering effects of a strong El Nino have left the Amazon its driest in 14 years, and recent research has suggested some parts are at "extreme risk" of wildfires this summer.

"We see drier than normal conditions in the Amazon region, which has also historically led to more fire activity," said Robert Field, a researcher with NASA's Goddard Institute for Space Studies, in an interview with CNBC. "So one particular impact there, is, depending on what is happening on the ground, and the direction of the winds, the Olympics could be affected if the smoke is blown into Rio."



Rio de Janeiro certainly would not be the first Olympic city to deal with lower air quality. Beijing hosted the Games in 2008, and the city's infamous air pollution problem was a major topic of concern.

Wildfire pollution is already causing concern in California, where massive fires have been burning this summer.

A recent air quality advisory from the Monterey Bay Air Resources District, a local agency in Monterey County, California, said, "If it looks smoky outside, it's probably not a good time to go for a run. And it's probably not a good time for your children to play outdoors."

Recently, wildfires in California led to air quality advisories in the San Francisco Bay area and the Los Angeles area, among other regions. Advisories were even issued in parts of Nevada, including Las Vegas — nearly 300 miles away from a fire north of Los Angeles.