INDIANAPOLIS — This weekend, if you’ve noticed the sun is redder than usual, your eyes aren’t fooling you.
Residents of Indiana, California, Washington, Oregon and even Hawaii have noticed the sun appearing reddish orange, and experts say the color is due to particles of smoke high in the sky that have blown wildfires in the western United States.
“We had smoke in the air, and it made it look pretty hazy there,” said Kacie Hoover, a meteorologist with the National Weather Service. “Even though there aren’t a lot of clouds, it still looks cloudy because the smoke filters that sunlight.”
These smoke particles scatter the light more, giving the appearance of longer wavelengths of light, which appear red.
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The smoke over parts of the eastern United States is the result of wildfires that have ravaged hundreds of miles of land. In California, the flames have forced many people to flee their homes and left thousands of firefighters scrambling to fight the blazes.
And although the fires have been raging for months now, Hoover said some might just notice the change in the sky due to the current weather. The presence of smoke in the sky largely depends on the air flow. The way the air high in the atmosphere was moving last weekend, “the smoke was just sort of there.”
In central Indiana, a high pressure system has swept over the area over the past few days, creating clear conditions that have made the phenomenon more evident.
The impact of this smoke goes beyond visual effects.
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Forest fires emit volumes of microscopic smoke particles that researchers say can be harmful if inhaled. Parts of the Northwest and upper Midwest have issued air quality alerts in recent weeks.
But experts say the smoke is probably not enough to create a health hazard. The smoke particles are high in the sky, they say, and the smoke from last weekend wasn’t terribly thick.
“Here,” Hoover said, “it’s just very high up and not much is coming to the surface.”
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