Category: "Ice Science"

The Curious World of Ice and Snow: Part 3 of 3

February 8th, 2020
These 14 slides are the final (third) section of my Science Cafe talk. (Plus two slides added as an introduction.) As in the previous section (previous post), this section mostly has ice forms that come from the melt, but the ice shapes here are a… more »

The Curious World of Ice and Snow: Part 2 of 3

February 8th, 2020
As I mention in Part 1, these are slides I gave for a Science Cafe discussion session in 2012. This section focuses on ice that forms directly from the melt, that is, the liquid phase. Contrast these cases with those in part 1 in which the ice grew from… more »

The Curious World of Ice and Snow: Part 1 of 3

February 4th, 2020
In 2012, I gave a "science cafe" talk with a local series sponsored by the Pacific Science Center, KCTS public television, and Science on Tap. The title was "The curious world of ice and snow". The location was a bar in Kirkland, but open to all ages.… more »

The Growing Icicle's Hollow Tip

January 17th, 2020
If you inspect the tip of a growing icicle, you might be surprised to find it hollow. Skeptical? Well, if you think the conditions suitable for icicles outside, put a toothpick in your pocket and go outside. Then when you see a likely candidate, poke… more »

Martini Hoar (raise a tiny glass?)

October 19th, 2019
The hoar-frost crystal shoots up like a thin, solid straw, then suddenly opens up into a cup-like shape. I have seen it often enough to give it a name: "martini hoar". The cup can be weirdly segmented and polyhedral, but it nevertheless widens suddenly.… more »

Puddle gets its grooves (upon freezing), part I

February 16th, 2019
These grooves appear on the surface of frozen puddles. [image:111] Most grooves are straight lines, and most of these also appear to have relatively symmetric sides, such as those marked #s 1, 2, & 4 in the above image. But some, such as #3, have… more »

Grain boundaries between crystals in big ice

November 6th, 2017
Most snow crystals are single crystals. Being single is an outcome of their growth process and small size. On the other hand, most larger ice formations are not single crystals. These latter types are called "polycrystals". A polycrystal usually appears… more »

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… more »

Lots of Hair Ice

December 19th, 2014
My older sister sent me this photo on a recent morning. This is hair ice growing from an alder tree. All of it grew overnight, formed when liquid water near the outer trunk surface (beneath the bark) froze. This creates an ice front in each pore-like… more »

Glaze-rime Ice Buildup Facing Creek

November 23rd, 2014
Here's a reed of some sort, with a glaze of clear rime on the side facing a creek. How did the clear ice get there, and what is the white ice on top of it? The fact that the clear ice is just on the side facing the creek indicates that the ice came from… more »