Basis Grade 5 Glacier Notes + Central Us Map 10/28/15

Front 1

Glaciers are masses of _____ ice created by the natural forces of _______ snow.

Back 1

moving

compacting

Front 2

A _____ is an almost motionless mass of ______ snow and ice that accumulates year after year. It is only considered a glacier if it is moving.

Back 2

snowfield

permanent

Front 3

Random melting occurs periodically, and then it _____. This changes the snow into ice crystals called ___.

Back 3

refreezes

firn

Front 4

In the deepest layer, the pressure of the layers above flattens the ice and squeezes out any ____. the firn loses its white color, turning a bright , ___-___ color.

Back 4

air

steel-blue

Front 5

A glacier is formed when _____ begins to pull the ice and snow down-slope.

Back 5

gravity

Front 6

Glacier growth depends on the balance between snowfall received and the amount of ice lost due to _____ and ______. More snow has to fall than the amount of water evaporating in order for ____ to occur.

Back 6

melting and evaporation

growth

Front 7

There are two types of glaciers. They are classified by their ____ and ____ they are formed.

Back 7

size

where

Front 8

Valley glaciers are long, narrow ____-shaped masses of ice. They form in high mountain regions. After they melt away, a _- shaped valley is left behind due to the bottom of the glacier ____ the valley floor away.

Back 8

wedge

U

eroding

Front 9

Continental ice sheets are ______ that cover large area of land. They occupy _____ of square kilometers of land.

Back 9

glaciers

millions

Front 10

Today, continental ice sheets only cover ____ and _______.

Back 10

Greenland

Antarctica

Front 11

Although glaciers are referred to as ____ of ice, they do not flow as freely as __(same)__.

Back 11

rivers

Front 12

Glaciers move of average ___ km/yr.

Back 12

100

Front 13

Glaciers move by 2 processes- ____ ___ and ____ ____ ___.

Back 13

basal-slip

internal plastic flow

Front 14

Basal slip. The weight of the ice adds enough ____ to melt the ice where it comes in contact with the ground at the bottom of the ____.

Back 14

pressure

glacier

Front 15

Basal slip. The water from the melted ice acts as a ______ (making it slippery) between the base of the ice and the ____ that it sits on. This allows ice to move ____ by slipping at the bottom.

Back 15

lubricant

rock

forward

Front 16

Internal plastic flow occurs when the ice crystals inside the glacier ____ over each other, causing a slow forward motion. (Yes, even solid ice can flow with enough weight and _____!)

Back 16

slip

pressure

Front 17

Since the ______ of the glacier is not under as much pressure, it remains _____.

Back 17

surface

brittle

Front 18

The surface buckles and cracks from the pressure creating _____.

Back 18

crevasses

Front 19

Continental ice sheets move outward in ___ directions from their center, eventually flowing into the ocean forming ___ _____.

Back 19

all

ice shelves

Front 20

The ocean waves break pieces off the ice shelves creating _____ (large chunks of ice that float out into the ocean).

Back 20

icebergs

Front 21

Icebergs are mostly under water with just the ___ part above the surface.

Back 21

top

Front 22

Back 22