Korea is one of the country where water is in short supply

The amount of annual average rain water in Korea is 1,357mm (‘81~’10). It is greater than that of the average annual precipitation of the world. However, the precipitation per capita is lower than the precipitation per capita in the world average.
About two-thirds of precipitation is concentrated in summer. Most of rain water flows to sea through rivers because of the fact that the river gradient is steep due to the mountainous geographical nature. About 31% of the total water is thrown away to sea. If evaporation loss is added, the amount of water for actual use is only 27%.

What is precipitation?

Precipitation consists of rainfall, snow and hail which fall on the surface of the earth. Precipitation is normally expressed as a millimeter in a unit of length. Solid matter such as snow and hail is measured by dissolving it. Total amount of rainfall is called as rain and the total amount of snow and hail is called as snowfall, these are taken together as precipitation.
Precipitation = rain (total amount of rainfall) + snowfall (snow, hail in total)

Water resource usage

Type of precipitation

Drizzle

Light rain formed in small water drops with 0.1~0.5mm diameter. Rainfall intensity is less than 1mm / hr.

Rain

It is formed by water drops (or more in diameter 0.5mm) from the cloud.

Hail

Frozen materials resulting from rain and drizzle being contacted with cold air on ground. The weight is 0.8~0.9g.

Sleet

Raindrops become frozen when rain drops are falling down.

Snow

Water vapor in the atmosphere is directly transformed to ice material.

Snowflake

Multiple ice crystals are frozen simultaneously and transformed.

Hail

Precipitation of the state of the mass of ice diameter 5~125 mm. It is a small piece of ice that is formed by frozen action due to turbulent air flow exchange.

Drizzle

The water enriched from the atmosphere as a droplet on a cold surface.

Frost

Dew or frozen vapor formed on the exposed surface of the object. The weight is 0.2~0.3g.

Fog

Thin clouds with a variety of sizes formed on the surface of the Earth due to concentration of atmospheric water vapor.