Snow

Snow falls when the air temperature is below freezing. Snow forms when water freezes in a cloud and turns into snowflakes as they fall through the cloud. No one has ever seen two identical snowflakes. The shape of snowflakes depends on the temperature and height they were formed.


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The Fall 2009 issue of The Earth Scientist, which includes articles on student research into building design for earthquakes and a classroom lab on the composition of the Earth’s ancient atmosphere, is available in our online store.

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The Earth Scientist, Volume XXV, Issue 3, Fall 2009

The Fall 2009 issue of The Earth Scientist includes a collection of Earth and Space Science articles for you, covering the current efforts to save Louisiana’s Lake Pontchartrain, student research into building design as it relates to earthquake damage, an exciting Earth Science project and resource from the United Kingdom...more

Rain

Rain is precipitation that falls to the Earth in drops of 5mm or more in diameter according to the US National Weather Service. Virga is rain that evaporates before reaching the ground. Raindrops form...more

Sleet and Freezing Rain

Sleet forms when a partially melted snowflake or raindrop turns back into ice as it is falling through the air. Sleet starts out in the clouds as a snowflake or a raindrop. If it starts out as a snowflake,...more

Drizzle

Drizzle is light precipitation that is made up of liquid water drops that are smaller than rain drops. Drizzle can be so light that only a millimeter of water falls to the Earth's surface in one day. It...more

Rain Shadow

A rain shadow is a dry region of land on the side of a mountain range that is protected from the prevailing winds. Prevailing winds are the winds that occur most of the time in a particular location on...more

Altocumulus

Altocumulus clouds are part of the Middle Cloud group (2000-7000m up). They are grayish-white with one part of the cloud darker than the other. Altocumulus clouds usually form in groups and are about...more

Altostratus

Altostratus belong to the Middle Cloud group (2000-7000m up). An altostratus cloud usually covers the whole sky and has a gray or blue-gray appearance. The sun or moon may shine through an altostratus...more

Cirrocumulus

Cirrocumulus clouds belong to the High Cloud group (5000-13000m). They are small rounded puffs that usually appear in long rows. Cirrocumulus are usually white, but sometimes appear gray. Cirrocumulus...more

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