Category: "Cloud science"

How clouds form snow

January 14th, 2017

To understand snow formation, one must know a little about clouds. 

Q: What is in a cloud?

A: Air, dust, vapor, droplets, and often, ice. 

Q: How much air? How much liquid water? How much ice?

A: The answers will probably surprise you. See my short 20-min presentation below. I gave this recently to the Bellingham, WA Snow School. (23 slides, but due to file-upload-size restrictions, I had to put them into three parts below, 10 slides, 6 slides, 7 slides.)

Snow, rain, and weather affect everybody, yet how many of us learned in school even the most basic facts about precipitation in school?

Q: Who first realized how ice grew in a cloud?

How clouds form snow

As described in my presentation, he realized this by observing frost on the ground. 

Q: Who first realized how Alfred's theory was intimately connected with rainfall? 

How clouds form snow

Tor discovered this by observing fog in a mountain forest, and like Alfred, applied some of his physics knowledge. 

In my presentation, I discussed Alfred Wegener, the roles of the different cloud components, and briefly how the ice, once formed, takes on its strange shapes: 

 

First 10 slides (with blue text added to account for the things I said during the talk):

http://www.storyofsnow.com/media/blogs/a/Jan2017/snowschool_annotated1t10.pdf?mtime=1484585328

 

Next 6 slides:

http://www.storyofsnow.com/media/blogs/a/Jan2017/snowschool_annotated11t16.pdf?mtime=1484585328

 

Last 7 slides:

http://www.storyofsnow.com/media/blogs/a/Jan2017/snowschool_annotated17t23.pdf?mtime=1484585309

 

 

Later, I will show specifically how the ice gets arranged into all these strange shapes. 

- JN