Page 379 - Laboratory Manual in Physical Geology

ACTIVITY 13.1 Cryosphere Inquiry

Name: ______________________________________ Course/Section: ______________________ Date: ___________

A. The cryosphere is all of Earth’s snow and ice.

1. In FIGURE 13.1 , what is the sequence of cryosphere regions that you would encounter on the ground if you traveled from

Mexico (a beige- to yellow-colored region with no snow or ice) to the North Pole?

2. Notice in FIGURE 13.1 that mountain glaciers and ice caps occur in parts of Greenland, Canada, Russia, Alaska, and

the western conterminous United States. Some mountain glaciers also exist very close to the equator (not shown in

FIGURE 13.1 ). How do you think it is possible for glaciers to exist at the equator?

3. If the temperature of Earth’s atmosphere were to rise, then how do you think it would affect the cryosphere, hydrosphere,
and biosphere?

4. If the temperature of Earth’s atmosphere were to cool, then how do you think it would affect the cryosphere, hydrosphere,

and biosphere?

B. Snow and glaciers are two of the best known parts of the cryosphere. Notice the snow and glaciers in the satellite image on the

next page. It is a perspective view, looking north, of part of the Himalayan Mountains and was made by draping an ASTER
natural color satellite image over a digital elevation model (by the NASA/GSFC/METI/ERSDAC/JAROS and U.S./Japan
TM
ASTER Science Team). You can view the same region in Google Earth by searching for coordinates 28 09 38 N, 90 03 05 E.
The glaciers in the satellite image formed by compaction and recrystallization of snow at higher elevations. Then they
flowed downhill, where they eventually melt. A glacier’s mass balance is the difference between the mass of its ice that is
accumulating and the mass of ice that is melting. If a glacier has more ice accumulating than melting, then it has a positive
mass balance and will advance downhill. If a glacier melts faster than it accumulates ice, then it has a negative mass balance
and will retreat (melt back).

1. The satellite image was acquired in summer of 2009, after most of the seasonal snow had melted. Using a pen, draw a line
along the snowline —the line between areas with snow (higher elevations) and areas with no snow.

2. Place arrows on the glaciers to show their direction of flow, like a river of ice.

3. Label the “area of snow and ice accumulation” and two “areas of ablation” (glacial melting).
4. Label the area where the glaciers have “positive mass balance” and the areas where the glaciers have a “negative

mass balance.”
5. Is the mass balance of the snowline that you drew in part B1 positive, negative, or neither? Why?

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