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Here's why it's been so bright across Central Indiana lately

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Posted at 7:01 PM, Feb 03, 2021
and last updated 2021-02-03 19:01:06-05

We count ourselves lucky for sunny days this time of year. Winter can be a rather gray season across Central Indiana, but the last couple of days have been extra bright! That's all thanks to a weather word you might not hear very often. Albedo! That's another way of saying reflectivity.

Here's how it all works.

The solar radiation from the sun shines down on us. The amount of that energy that is absorbed by the surface depends on how bright or dark that surface is. The snow we received recently has a very high albedo, or reflectivity. This means nearly all of the sun's energy bounces off the ground and back into the atmosphere. That's why you've really needed the sunglasses for the extra bright conditions the last few days. This high reflectivity is also the reason snow on the ground can keep our temperatures colder than if we had no snow at all.

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On the flip side, darker surfaces absorb more solar radiation. That's why asphalt can really be hot on your feet in the summer, compared to the grass.

If you forget the sunglasses when heading out for a run or walking the dog the next couple of days, you won't be blinded by the bright conditions. That could change again this weekend though. We're expecting light snow Saturday night with some sunshine to follow Sunday.

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