Increased Nacreous Clouds: A sign of colder upper air temperatures

This from www.Spaceweather.com

As January comes to an end, sky watchers in Scandinavia are recovering from a veritable storm of nacreous clouds. After mid-month, hardly a night went by without someone spotting the phenomenon. “It was incredible! They were all over the sky,” says Morton Ross of Oslo, Norway. This picture, taken by Ross on Jan. 25th, shows a typical apparition:

Also known as “Mother of Pearl” clouds, nacreous clouds are peppered with tiny ice crystals that blaze with iridescent color when struck by light from the setting sun. It is these crystals that make nacreous clouds so rare: they require exceptionally low temperatures of minus 85 Celsius (-120 F) to form. Icy nacreous clouds float 9 to 16 miles high, curling and uncurling hypnotically as they are modulated by atmospheric gravity waves.

For much of January, these clouds rolled across the Arctic circle with puzzling regularity. Why the sudden abundance? Is the show over? No one knows. Stay tuned for February!

For more, see the 2008 Nacreous Cloud Gallery For the science behind nacreous clouds, please see this entry in Atmospheric Optics.

As for temperatures at high latitudes, its -35°F in Saskatoon at the surface this morning, so there’s a chance we’ll see more nacreous clouds in days ahead.

tempcity_nat_320x240.jpg

About these ads

9 thoughts on “Increased Nacreous Clouds: A sign of colder upper air temperatures

  1. Too bad there isn’t a nacreous cloud index. It would be interesting to see if the these clouds are correlated with the onset of significant (long-term) changes in climate, especially for the Northern Hemisphere. One also wonders if there is any mention of them in Scandinavian folklore.

  2. A portent of killer ice? (Killer ice, as opposed to say, killer AGW, or killer bees – it’s killer ice that I worry about, not the other two.)

  3. it’s killer ice that I worry about, not the other two.)

    I’ll second that, Steve. Who in their right mind wants to go back to the winters we had in the midwest back in the 60′s, 70′s and early 80′s when night time low temperatures of -10 to -20 were not uncommon along with days at a time where the daytime high never got above single digits. No thanks.

  4. So does anyone have a guess as to where the month of Jan 2008 will be in terms of temperature? From all the press on snow and cold you would think it would be one of the coldest months in a long time.

  5. I’ll second that, Steve. Who in their right mind wants to go back to the winters we had in the midwest back in the 60’s, 70’s and early 80’s when night time low temperatures of -10 to -20 were not uncommon along with days at a time where the daytime high never got above single digits. No thanks.

    Sounds like the winters I spent in Illinois from Feb 2004 to 2005…. Doesn’t seem like things have changed.

  6. Well, this is a prediction, of sorts, from the AGW crowd. Stratospheric cooling. Of course ozone fits in the picture somehow. High level ice at a cold enough temp depletes ozone.

  7. this world is getting hotter thermal images shown that heat has risen 2.5 in the last 60 years and if it continues that way bye 2090 we will be extinct because of the heat you think -10 is bad weather wait until you get 130 degree weather with no rain. water levels would rise and there you go acid rain would fall and fall until it turned it self to sulfuric acid compound thats eats away material and you think that that you woudnt miss that weather Stan Need ham. just wait because my children will have to live in a destroyed world

    REPLY: This recent post might be more on par with your thinking.

Comments are closed.