Pinnacle Press Inc. Saint Louis, Missouri

Copyright ©2014 by Lindsay Ruck

All Rights Reserved. This book or any portion thereof may not be reproduced or used in any manner whatsoever without the express written permission of the publisher except for the use of brief quotations in a book review.

isbn Number 0 - 9719857 - 0 - 0

Pinnacle Press Inc.5900 Berthold Ave.St. Louis, Missouri 63110

Book design by Lindsay Ruck

Printed in the United States of America

Dedicated to those working

the graveyard shift at Kinko’s.

Thank you.

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5

7

Intro

what is a snow crystal?

the crystalline ice structure

snow crystalformation

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3

5

7

Intro

Looking up at the sky on a brisk, winter day, you might find tiny flakes dancing through the air as they make their way towards the earth. If you live in a part of the world where cold temperatures frequent the latter months of the year, chances are that you’ve encountered this phenomenon known as snow. Creating majestic landscapes across plains, mountains, and even your backyard, snow is one of Earth’s most alluring atmospheric gifts. These striking winter wonderlands, however, would not be possible if it weren’t for snow crystals. Without snow crystals, there would be no White Christmases or beloved snow days. Certain species of animals would fail to exist. The world, without them, would be a much less interesting and inspiring place. Snow crystals build the foundation for snow and snow accumulation. It is estimated that each year, a million billion cubic feet of snow falls to the Earth. All of this snow weighs in at roughly a million billion kilograms. As a typical snow crystal weighs around one millionth of a gram, this means that a cubic foot of snow can contain close to one billion crystals! Most snow crystals measure at less than one half-inch across, while the smallest may only be four-thousandths of an inch. These crystals are sometimes microscopic and not visible by the naked eye. Under certain conditions though, larger crystals can occur, some measuring up to two inches long. In fact, the world’s largest snow crystal that occurred in Montana in 1887 was almost fifteen inches wide and 8 inches thick! These snow crystals come in a wide variety of shapes and sizes, all depending on changing atmospheric conditions. This makes for extraordinary diversity in the crystals. You might have heard the old adage that “no two snowflakes are alike.” You won’t find two complex snow crystals that look exactly identical. However, this does not hold true for all snow crystals. All snow crystals begin as simple, hexagonal prisms. When they are in the very early stages of formation, these hexagonal prism crystals may look alike, but they quickly change as the atmospheric conditions become increasingly unstable. Thus, it is highly unlikely that any two complex crystals in the history of snow crystals have ever looked completely alike.

This book takes a simplified look at snow crystals, in all their wonder, defining what exactly a snow crystal is, the structure that makes up the crystals, and finally, their formation. Enjoy!

what is a

snowcrystal?

A snow crystal is a

single crystal of ice where

its internal symmetry is

reflected by a regular

surface pattern.

The term “snowflake”

means anything from

a single crystal of ice

to several crystals

stuck together.

4

what is a

snowcrystal?

o

h

h

Snow crystals are composed

of hydrogen and oxygen. For

every oxygen atom, there are

two hydrogen atoms, creating

the water molecule H2O.

Oxygen

Hydrogen

The water molecules form

a hexagonal lattice as the

snow crystals grow larger.

o

H

H

Oxygen

Hydrogen

That’s how snow crystals get

their six-fold symmetry. The

structure of the lattice is re�ected

in its external structure.

Hexagonal Lattice

thecrystallineice structure

15

o

h

h

Snow crystals are composed

of hydrogen and oxygen. For

every oxygen atom, there are

two hydrogen atoms, creating

the water molecule H2O.

Oxygen

Hydrogen

The water molecules form

a hexagonal lattice as the

snow crystals grow larger.

o

H

H

Oxygen

Hydrogen

That’s how snow crystals get

their six-fold symmetry. The

structure of the lattice is re�ected

in its external structure.

Hexagonal Lattice

7

Every snow crystal begins

as a dust particle in the clouds.

Water molecules then

condense onto the surface

of the particle, and then onto

each other in a hexagonal

lattice formation.

1

2

snow crystalformation

9

3

4

The hexagonal lattice then

begins to grow into a prism.

Depending on the conditions,

different surfaces grow at

different rates.

When the temperature changes,

it causes arms to grow on the

corners. The arms grow faster

than the rest of the crystal and

become more prominent.

20

The temperatures and conditions

continue to change as the snow

crystal falls through the air causing

plate growth to change further.

Different temperatures and

varying conditions create

different crystal shapes.

12

5

This book was created by Lindsay Ruck under the supervision of Jennifer McKnight as an assignment in Advanced Problems Graphic Design II in the Spring semester of the year 2014 at the University of Missouri - St. Louis. Spreads were composed in Adobe InDesign CS5. All patterns and design elements were created in Adobe Illustrator CS5. The typefaces used were Caecilia lt Std and Intro, all varying in weight and size. The book is printed on 11x17 32lb bright white laser paper.