Diamond Dust

Have you ever found yourself outside on a cold, clear, still day and noticed a snowfall? No clouds above to produce the precipitation; no gusts to blow up fallen snow.

If so, you might have experienced a phenomenon known as diamond dust.

If you’ve never seen this strange happening, you’re not alone. Diamond dust is extremely rare, as it usually requires a frigid temperature – often below 0 or -10 degrees Fahrenheit – to manifest.

The dust is a cloud of ice crystals at ground level. These clouds can form when water vapor turns directly into ice. In the video above, you can see the difference between fog and diamond dust. We call clouds near the ground fog when they are comprised of liquid water instead of ice crystals.

This phenomenon is also called clear-sky precipitation because clouds in the sky do not yield this precipitation. The cause of diamond dust is usually temperature inversion. Normally, as one rises higher and higher in Earth’s atmosphere, the air temperature drops. In certain situations, this rule flips. During a temperature inversion, the relative humidity near the ground can increase, as warmer air and its higher water vapor contents mix with colder air, bringing moisture toward the ground. This unusual brew of conditions provokes diamond dust.

The colloquial name arose because the crystals can reflect sunlight in such a way that the air glitters like beacons shining on dangling diamonds.

Because the dust requires cold temperatures, it is most common in Antarctica and above the Arctic Circle. In these chilly locations, diamond dust can persist for days at a time. Scientists report more than 300 days per year of diamond dust at Antarctic research stations.

As you can see in the above video, however, other locations can experience the gorgeous clouds. Alaska, Canada, and portions of the northern contiguous United States sometimes hit the low temperatures needed for diamond dust.

One of the greatest parts about researching topics for The Mountains Are Calling is the connections that arise between topics. Sometimes a subject is so grandiose it can spawn multiple other articles. These associations are akin to connect-the-dots, as I follow the beauty where it leads. Sometimes, though, topics associate themselves serendipitously.

Our previous rumination explored Xiaohaituo Mountain, the spot at which alpine skiing events transpired at the 2022 Beijing Winter Olympics. This crag is wonderful, but it lacks much natural snow. As such, the Chinese pumped out artificial snow in great quantities to make the mountain white. It just so happens that diamond dust can be created artificially. At resorts that employ snow machines to populate themselves with skiable powder, diamond dust can sometimes be seen near the devices!

As it turns out, the subject of diamond dust crossed our desks before we decided to profile the Chinese mountain. But, because of the timing of the opening of the Games, the article on the Olympics demanded an earlier publication. So, the genesis for this episode came before the previous one, but its research occurred after the fact. What a lovely surprise to read diamond dust literature to find a connection to snow machines!

Perhaps the Olympians will enjoy two weeks of diamonds flittering through their peripheral vision!