Ice and Snow

Snow crystals courtesy of SnowCrystals.com

Water is a polar covalent molecule.

Because of this one water molecule is attracted to another.The temporary bond formed is called a hydrogen bond

This attraction gives water a high surface tension. This allows some creatures to actually walk on water.

This water strider can walk on the surface of the water because the hydrogen bonds form a weak skin. This phenomena of water

attracted to itself is called cohesion

Cohesion is what holds a water drop together

More cohesion

A water drop at the Space Station

• wringing out a washcloth in space.

Adhesion and capillary action

When water freezes the brief temporary hydrogen bonds of liquid water become permanent and the

molecules are forced apart.

The shape of the water molecule and its angle causes the hexagonal crystals and snowflake designs.

Blue Ice

• Glacial ice is a different color than regular ice. It is so blue because the dense ice of the glacier absorbs every other color of the spectrum except blue--so blue is what we see!

• It's Not regular Frozen Water!• Sometimes the glacial ice appears almost turquoise. Its crystalline structure

strongly scatters blue light. The ice on a glacier has been there for a really long time and has been compacted down so that its structure is pretty different than the ice you normally see. Glacial ice is a lot different than the frozen water you get out of the freezer.

Blue Ice is Unique

• It's Not Frozen Snow!• Glacial ice is not just frozen compacted snow. • There are other things in the ice that make it much different than the ice in your home. • Glaciers move through rock and soil as they carve their way down a slope. • This means the ice is going to have a lot more ingredients than just water.

Ancient Compressed Ice

• What would happen if you broke off a big chunk of ice from a glacier and put it in your glass of water? Would it be any different than the ice in your freezer at home? What would happen to all those air bubbles that have been trapped under pressure?

• * If your chunk of glacial ice melted in your glass of water, then you would have dirt, gravel, and even organic matter [living stuff] in your water.

• * All those pressurized air bubbles would rush out so fast, they might explode your glass.

Antarctic Ice Cliff