Bad Astronomy

Lovely, frigid ripples

The weather here in Boulder has been pretty warm lately, and most of the snow is gone. I know that this can change at any moment (and in fact we’re due for more snow in a day or so), and NASA has provided a chilling but ethereally lovely reminder that this winter has been one to remember:

This image was taken by the Terra satellite on January 24, and shows what happens when there is a confluence of three conditions. The first is extremely frigid arctic air blowing down from the north west. The second is warmer waters in the Atlantic; the air above the water gets humid and rises into the colder air, condensing to form clouds. But the third is what’s needed to make this amazing rippling effect: a layer of warm air above the cold layer, called a temperature inversion. This acts like a ceiling for the rising, condensing air below. The clouds that form can’t rise any higher, so they roll east with the moving air, forming these “streets”.

I think the effect of this image is heightened by the lack of clouds over land; it’s the ocean water that creates the clouds, so the skies were clear over the Atlantic seaboard, allowing us to see the snow-covered landscape. I like to think of how much meteorologists and climate scientists can learn from images like this, and of course that’s why we launch satellites like Terra into orbit. But I also don’t have too much of a problem just sitting back and admiring the beauty and artistry of our planet from space, either.

Image credit: NASA, Jeff Schmaltz, MODIS Rapid Response Team, Goddard Space Flight Center. Addition credit to my old pal Michael Carlowicz.

Related posts:

- The cloudy, warming Earth
- Plume and ash
- Ephemeral snow and ancient rock
- Snowpocalypse 2011