Mini Season: Major Snow

We have entered the mini-season of Major Snow.  This season runs from December 07 until December 21.  This mini-season contains the micro-seasons of:

• The Sky is Cold, Winter Comes (Dec. 07 – Dec. 11)
• The Bear Retreats to its Den (Dec. 11 – Dec 16)
• The Salmon Gather to Spawn (Dec 17 – Dec 21)

These seasons were established in 1685 by Japanese astronomer Shibuka Shunkai and are specific to Japan. However, just because the calendar focuses on Japan doesn’t mean it isn’t applicable to others.  No matter where you live you can use these seasons as a starting point for your personal exploration of the world around you. 

As a way to celebrate this season, we will look at how frost is made and then read some poetry by Issa, Buson, Toshimi, and Teasdale.

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The mini-season of Major Snow is marked by a drop in temperature and a noticeable decline in daylight.  With this shift, scraping ice off the car’s windshield and frost gathering in the corners of windows is now a common occurrence. 

What is Frost?

Frost occurs when water vapor turns solid on cold surfaces.  This is a multiple step process that starts with air moisture that condenses into liquid when the temperature drops. Then, as it continues to get colder the liquid freezes on surfaces. The freezing process turns the liquid into ice.  The ice is then arranged into ice crystals, which make frost.

Frost commonly forms in low-lying areas where the colder air, which contains more moisture than warmer air, sinks into the valleys.  Lower lying areas also tend to be generally colder which makes it easier for frost to develop.

Types of Frost

There are four different types of frost: radiation frost, advection frost, window frost, and rime.  

• Radiation frost is small ice crystals that form on the ground or other objects that are close to the ground. 

• Advection frost forms on branches and poles and looks like very small ice spikes. This type of frost is formed as the cold air blows over these surfaces. 

• Window frost, as you can guess, is formed on windows.  This frost is a result of the colder outside air meeting the warmer, moister, air inside a house.  

• Rime frost forms in wet and windy climates.  This type of frost often looks like solid ice.  If you have ever seen pictures of the structures in the artic covered in ice, this is an example of rime frost.

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Besides being a fascinating natural process, frost is also a great kigo, or seasonal word, for haikus and other forms of poetry. Below I have collected a few examples of frost in poetry.

Frost in Haiku

Kobayashi Issa wrote the following frost-themed haikus.

frost has formed
on the futon...
Milky Way above

first frost--
the beggar's stove
a welcome sight

Yosa Buson wrote this one:

miles of frost –
on the lake
the moon’s my own.

And, the contemporary poet Horiuchi Toshimi wrote:

glittering flakes:
the wind is breaking
frozen moonlight.

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Frost also shows up in longer-form poetry like this one from Sara Teasdale.

“A December Day” by Sara Teasdale

Dawn turned on her purple pillow
— And late, late came the winter day,
Snow was curved to the boughs of the willow.
— The sunless world was white and grey.

At noon we heard a blue-jay scolding,
— At five the last thin light was lost
From snow-banked windows faintly holding
— The feathery filigree of frost

Notice how in Teasdale’s poem she talks about window frost, whereas Buson and Toshimi are probably talking about radiation frost. It is interesting to see both of these forms of frost show up in poetry.

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Resources:

• 72 Seasons App
• Frost; National Geographic Society
• Winter Haiku Collection; Japanpowered.com

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