Micro-Season: “Heavy Rain Showers”

We have entered the micro-season of “Heavy Rain Showers”.  This is the third micro-season of the mini-season of Major Heat.  The micro-seasons within Major Heat are:

• The First Paulownia Fruit Ripen (Jul. 22 –  Jul. 27)
• Damp Earth Humid Heat (Jul 28 – Aug 01)
• Heavy Rain Showers  (Aug 02 – Aug 06)

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 explore the water cycle and read some rain-themed haiku by Basho, Issa, and Buson.

The Water Cycle

Rain is just one part of the larger water cycle or hydrological cycle. The water cycle is the process that allows water to move from oceans, to clouds, to streams, and back again.  At its most basic form, the cycle works like this:

• Ocean water is warmed by the sun, it evaporates, it turns into water vapor, and then rises into the sky
• As the water vapor rises it begins to cool and condenses into clouds
• The clouds collect more water vapor until they can’t hold anymore
• The clouds then begin to release the water in the form of precipitation
• Depending on the temperature, the precipitation can be in the form of snow, sleet, hail, or rain
• Once the precipitation hits the ground it either joins the rivers and streams, soaks into the earth, or runs off the surface to join some other body of water such as the ocean.
• At this point, the water cycle repeats

The above explanation is a very simplified version of this process.  The graphic below created by Dennis Cain at the National Weather Service illustrates many of the ways water moves including transpiration (plants to atmosphere), sublimation (snow and ice directly to gas), and percolation (water into the ground).

Precipitation

Precipitation is described as an atmospheric phenomenon in which water falls from the sky and reaches the ground.  Precipitation can be either liquid or solid depending on the atmospheric temperature. 

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When the atmospheric temperature is below freezing, the precipitation is solid and could be in one of the following forms. These descriptions are courtesy of the National Weather Service.

Ice Pellets or Sleet

Ice pellets or sleet are described as transparent or translucent pellets of ice, which are round or irregular hard grains of ice consisting of frozen raindrops or melted then refrozen snowflakes.

Hail

Hail falls in the form of small balls or other pieces of ice falling separately or frozen together in irregular lumps. Associated with thunderstorms, individual hail stones are ¼ inch (5 mm) or greater in diameter. Hail sizes of 1 inch (2.5 cm) or more are indicative of severe thunderstorms.

Snow Pellets

Snow pellets are white, opaque grains of ice that are round or sometimes conical. Diameters are less than ¼ inch (5 mm).

Snow

The term “snow” is used to describe snow crystals that are mostly branched and in the form of six-pointed stars.

Ice Crystals

Ice crystals occur in very cold regions. Ice crystals are falling ice that is in the form of needles, columns, or plates. Also called ‘diamond dust’, ice crystals appear like fog with individual water particles forming directly as ice. The shape of the individual ice crystals causes the ‘light pillar’ optical effect above the light source.

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When temperatures are above freezing the precipitation is in liquid form and can be in the following forms. These defintions are courtesy of the National Weather Service.

Drizzle 

Drizzle is defined as fairly uniform precipitation that is composed exclusively of fine drops very close together. Drizzle appears to float while following air currents, but unlike fog droplets, it falls to the ground. Quite often fog and drizzle occur together.

Rain

Rain is the most commonly observed form of precipitation.  When drops are larger than drizzle (0.02 inch / 0.5 mm or more) it is considered rain. However, smaller drops are also considered raindrops if, in contrast to drizzle, they are widely separated.

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Types Of Rainfall

As this micro-season talks about rainfall, it is important to identify what exactly is “Heavy Rain”. 

“Heavy Rain” is a term associated with a specific rate of rain falling per hour.  There is also light, moderate, and violent rainfall.  The following list explains the difference between these terms.⁽³⁾ 

• Light rain falls at a rate of between  a trace to 2.5 millimeters ((0.098 in) per hour
• Moderate rain falls at a rate of between 2.6 millimeters (0.10 in) to 7.6 millimeters (.30 in) per hour.
• Heavy rainfall at a rate greater than 7.6 millimeters  (0.30 in) per hour
• Violent rain falls at a rate greater than 50 millimeters (2.0 in) per hour

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Haiku about Rain

Similar to our exploration into dog haiku from last week, the word “rain” is not a seasonal word. Dr. Gabi Greve explains, “Expressions like ‘long rain, strong rain, gentle rain, soft rain, steady rain’ without the mentioning of a specific season are also NOT considered kigo but topics.”⁽⁵⁾ The reason for this is that rain can happen during most seasons. As result, to place a rain haiku within a season there needs to be another seasonal word.

Below are a few examples of rain-themed haiku from Basho, Issa, and Buson with various seasonal references.

Basho

The rainfall in June –
the poems I’ve pasted to walls
peel off, but leave traces.

a lonely moon:
from the eaves of the temple,
drops of rain

The “a lonely moon” haiku comes from Basho’s Kashima Journal. The World Kigo Database states, “The word moon without further connotation, refers to the autumn moon in Japanese haiku.”⁽⁶⁾ This haiku was written alongside many other autumn-themed haiku.

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Issa

the cut grass
sticks to my feet… 
autumn rain 

three raindrops
a greeting card from heaven...
midsummer heat

These haiku by Issa have very obvious seasonal references with phrases like “autumn rain” and “midsummer heat”.

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Buson

In the summer rain
the path
has disappeared

the rainy season
and the river with no name
a frightening thing

The “rainy season” is associated with mid-summer. However, some haiku poets consider the rainy season its own season.⁽⁷⁾

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Resources:

1. “Water Cycle”; National Oceanic and Atmospheric Administration
2. “Types of Precipitation” National Weather Service
3. “Rain”; Wikipedia
4. “Types of Precipitation”; National Geographic Resource Library
5. “Rain”; World Kigo Database
6. “Moon and related links”; World Kigo Database
7. “Rainy Season”; World Kido Database

• Basho haiku found in Basho’s Journey: The Literary Prose of Matsuo Basho translated by David Landis Barnhill
• Issa haiku are translated by David G. Lanoue at HaikuGuy.com. 
• Buson haiku are found in Three Simple Lines: A Writer’s Pilgrimage into the Heart and Homeland of Haiku By Natalie Goldberg

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