What happens to different isotopes of oxygen in this figure?

A. evaporation concentrates lighter isotopes in the resulting water vapor

B. precipitation forms ice that is enriched in heavier isotopes relative to seawater

C. melting of ice preferentially releases heavier isotopes back into the ocean

D. all of these

What is permafrost?

A. curly crystals of frost that form early in the morning

B. ice and snow that exist throughout the entire year

C. ice and snow that are permanently in motion

D. the upper part of the ground that remains frozen throughout the year

With the Sun and Moon in this position, what does the side of the earth facing the moon experience?

A. a normal high tide

B. a normal low tide

C. a spring tide

D. a neap tide .

What causes high and low tides?

A. the tendency for water on a spinning globe to be thrown outward

B. daily heating and cooling of the seas, which causes seawater to contract and expand

C. a rise in sea level during the day because of an increase in storms

D. water is pulled by the gravity of the Moon

E. all of these

What is the origin of smooth troughs (T on this figure) cutting across the landscape in the Great Lakes area?

A. the areas were covered by soft marine sediments

B. a huge flood coming from lowa flowed toward the Great Lakes

C. glaciers carved the smooth troughs

D. all of these

What are some possible influences of ocean currents on glaciation?

A. Cold currents can cool the land allowing glaciers to form if there is sufficient precipitation.

B. Cold currents can inhibit the growth of glaciers because they put less moisture into the atmosphere.

C. Warm currents can warm parts of continents, inhibiting glaciation.

D. Warm currents bring warm moist air that can increase precipitation and snowfall if the temperature is cold enough.

E. All of these.

Till is _______.

A. sorted but not stratified.

B. sorted and stratified.

C. stratified but not sorted.

D. neither sorted nor stratified.

The margins of glaciers are usually darker than the interior primarily because:

A. shearing causes the ice to expel air and become darker

B. glaciers are transparent so the underlying bedrock is visible

C. the sides are moving faster than the interior of the glacier

D. the sides have a higher concentration of rocks and other debris

E. all of these

The amount of solar heating can increase from:

A. a decrease in sunspot activity and energy output from the Sun

B. a decrease in snow and ice cover on Earth's surface

C. a decrease in the amount of greenhouse gases

D. a huge volcanic eruption that adds ash and dust to the atmosphere

What is this bowl-shaped, glacially carved feature?

A. hanging valley

B. arete

c. cirque

D. continental ice sheet

When will an area experience high tide?

A. in the early afternoon when water temperatures are highest

B. when there is a quarter moon in the sky

C. when the moon is directly overhead or on the opposite side of Earth

D. during a period of intense sunspot activity

In the accompanying hydrograph for major river, a flood was caused by a single episode of heavy rainfall 50 kilometers upstream. When did the rain most likely occur?

A. at time $A$

B. at time B

C. at time $C$

D. at time D

(a) What is an interglacial period? (b) How frequently do warm interglacial periods occur? (c) Are we currently in an ice age or an interglacial period? (d) Has Earth spent more time in cold ice age periods or in mild interglacial periods over the past 400 000 years?

Which of the features labeled on this figure is a terminal or recessional moraine?

A. A

B. B

c. C

D. D

E. E