Yesterday I saw something that in my well over ten thousand evenings I have never seen before. It was mid-afternoon and had been a lovely day, so I decided to take a walk. Since moving to northern Sweden, I have developed the habit of taking walks in the afternoon in order to enjoy what light there is to enjoy. And since late December, the sunset has been receding deliciously in the direction of midnight, though at this point it still comes at about a quarter past three. So half an hour before then, I set out for a walk.
I crossed the bridge near my house and came to a park where I had a good view in all directions. Low, dark clouds were rolling in on the wind, which had started to pick up, but the sun will still trying to get through in the south-west. And then I noticed something higher up in the sky.
Above the gray and rumbling clouds rolling in over the hills, there hung a few thin, wispy clouds high up in the stratosphere. There were just a few of them, spread out not far from the sun: thin clouds with wispy edges. And they were glowing, but not white. One of them was bright pink, one was purple, one was green with blue edges. These clouds looked like pieces that had been ripped out of a rainbow and left hanging in the sky.
I had never seen anything like it. The clouds burned in incandescent shades of pistachio green, cherry-blossom pink, parakeet blue, sherbet orange. Clearly, they were refracting the light of the setting sun in some way. But the colors weren’t placed like those of a rainbow. It looked as though there had been some sort of celestial civil war, with the colors of the rainbow scattering and each one claiming what vaporous territory it could. Behind all, the sun kept pumping out its orange Feierabend rays, and down below, the dark clouds kept sweeping in like ill-tempered hooligans.
The show didn’t last very long, and I didn’t have my camera with me. As it happened, the cloud colors died down and the southern sky was stained a deep red, which prompted me to go up to the top of the highest hill in the area and watch the sun sink below the ridges to the west. But by then the strange phenomenon was over. Had I just imagined it?
I puzzled over this but remained ignorant until an article appeared today in Dagens Nyheter, the Swedish national paper, reporting that this rare phenomenon had also occured several hundred kilometers south of here and was called pärlemormoln, or mother-of-pearl clouds. Feeling the deep human joy of putting a name on a thing, I started to do some research, and learned that this is a sub-type of a phenomenon called polar stratospheric clouds. In a nutshell, it’s something that almost only happens very far north, like northern Scandinavia (which somehow used to sound more northern than it does now, but never mind) and happens only a few times each winter. Apparently, clouds form very high up in the stratosphere under very cold conditions, and can contain only ice crystals, or ice crystals mixed with nitric acid and sulfuric acid.
Mother of pearl clouds
I’ve found a picture on the Web of this phenomenon, which you see here. My clouds were more fragmented, and so each had fewer colors, but you get the general idea.
I was somewhat deflated by the further revelation—a perfect synecdoche of the zeitgeist, if you know what that means—that these clouds are implicated in the depletion of the ozone layer. There is just no escape from inconvenient truths nowadays, is there? However, I take heart in thinking that our clouds here in little Härnösand were probably the benign ice-crystal-bearing type. Sure looked that way to me, given my long experience with such things.
So, I may not yet have seen the aurora borealis, but at least I’ve now seen an arctic specialty that is even rarer. You never know what benefits will come from afternoon walks, and keeping your eyes off the ground.