Dennis Horwood
Long before microscopes or meteorologists, northern natives and Laplanders recognized different types of snow.
Traditionally, they called fresh, falling snow anniu. Snow already on the ground was referred to as api.
Avalanche experts, weather forecasters, skiers, snow boarders, along with anyone who has ever shoveled snow recognizes that snow changes.
In fact, snow reshapes its form and character from the moment of formation to the moment it melts.
Snow has a modest beginning. High in the clouds, a few molecules of water freeze around microscopic bits of dust. This minute core of frozen water attracts more molecules of water which also freeze and add their bulk to the ever increasing size.
The linking of water molecules, however, takes on a predictable pattern. Due to the nature of water, the freezing takes the shape of a six-sided figure. The particle, now noticeably larger, appears star-like with six pointed rays all joined in the middle.
Snowflakes at this stage exhibit endless varieties of details but always maintain their hexagonal pattern.
No sooner is a snowflake born than it begins to disintegrate. The force of gravity pulls them earthward causing airborne collisions with other snow crystals. The delicate points break or they may interlock with other flakes.
Strong winds toss and stress the crystalline structures and slight temperature changes cause distortions.
Despite atmospheric conditions, most snowflakes land basically intact. Freshly fallen snow tends to be fluffy and quickly builds into deep layers.
As the snow depth increases, so does the weight causing lower layers to compress. Ten centimetres of fresh snow can compact to less than half the original amount.
If the thermometer rises a few degrees, snowflakes loose their points and become granular. The snow now becomes dense as airspaces between the flakes become much smaller.
Snow at this stage still appears white but is very heavy to lift.
These changes in snowflakes are subtle and difficult to observe without specialized optical equipment. Studying snow crystals must be done in cold conditions, usually outside.
Even so, there are other ways to take note of changing conditions.
Snow on the tree branches is known as qali in Inuit. Qali produces beautiful and intricate patterns on trees, wires, and fence posts. The sharp, six-pointed crystals accumulate quickly and in a few hours can create spectacular winter scenes.
Qali is also less dense. Despite how beautiful the snow might be, this is the time to shovel your driveway or sidewalk.
If you wait for the snow to settle then the task of snow clearing becomes much more difficult. On the other hand kids enjoy this stage as forts, snowmen, tobogganing and snowball fights are at their best with tight, compact snow.
Even though most snow transformations occur without our eyes witnessing the events, the Inuit clearly had it right.
Snow is not necessarily just ‘snow’.
