Why Minnesota’s Night Sky Is So Bright After It Snows
After a fairly quiet start to the new year, Old Man Winter is back in Minnesota with snow in the forecast several times this week. Which has once again made me notice how light the sky is at night after it snows. Ever wonder why that is?
Seeing as I head into downtown Rochester well before the sun rises each day, I noticed both Monday and Tuesday morning (after several inches of snow had fallen overnight) just how our LIGHT our Minnesota sky seemed-- despite the fact that it was still dark out. In fact, I snapped that picture of our backyard at about 4:15 this morning and it looks amazingly light, doesn't it?
I also noticed this phenomenon in the evenings after we'd had snow earlier in the day. Have you noticed the same thing? Well, as it turns out, the night sky in Minnesota IS brighter and lighter after a snowstorm hits the Bold North. And, there's a fairly simple scientific explanation for it too.
This GO-MN story explains what happens after it snows: "We have our street lights, and when you have snow on the ground, that reflects a lot of light upwards into the atmosphere," Jacob Beitlich, a meteorologist from the NWS-Twin Cities, said in the story.
But wait, there's more: "If you have snow falling, all those tiny ice crystals scatter (reflects) a lot of that light, and a lot of it gets scattered back down to the ground," Beitlich said in the story.
He also noted that low clouds usually associated with a snow event tend to reflect the light back down to earth-- when, without the clouds, the light usually just escapes out in the atmosphere (and things look much darker outside.) He called the phenomenon the "scattering of light."
So, yeah. Sounds simple, but a lighter night sky in Minnesota after it snows IS a real thing. And now you know why.