Geography Chapter 17 Flashcards

Questions and Answers

________ deserts form on the leeward (dry) side of mountain ranges.

Subtropical

Rain-shadow (correct)

Coastal

Tropical

Deserts do not need to be in hot regions; they only need to be , for example, deserts can form in cold, dry, regions.

humid; subtropical

arid; polar (correct)

dry; tropical

humid; polar

According to the textbook, the highest recorded temperature on Earth was in a ________.

low-latitude, high-elevation desert in Mexico

low-latitude, low-elevation desert in Libya (correct)

high-latitude, high-elevation desert in Mongolia

tropical rain forest in Brazil

Deserts represent ________ of Earth's surface.

about 25% Signup and view all the answers

________ deserts occur due to the drying out of air masses over the equatorial rain forests.

Subtropical Signup and view all the answers

To qualify as a desert, a region must ________.

be arid, with less than 15% of the ground surface vegetated Signup and view all the answers

Desert climate associated with a rain-shadow is found ________.

on the leeward side of mountain ranges Signup and view all the answers

A desert may form along a coastline because a _____

cold current cools and dries the air Signup and view all the answers

Which desert is the result of air masses that dry out as they cross over land?

Gobi Desert Signup and view all the answers

The figure below illustrates the formation of a ________ desert.

coastal Signup and view all the answers

The deserts found in the western United States are primarily the result of being located ________.

within rain-shadows of mountains Signup and view all the answers

The measured rainfall shown in the figure below is characteristic of a ________ desert.

rain-shadow Signup and view all the answers

Why do deserts form at high elevations?

The air is too thin to hold much heat. Signup and view all the answers

Why do deserts form in polar regions?

Cold air does not hold much moisture. Signup and view all the answers

As shown in the figure below, wind erosion can create a faceted rock known as a ________.

ventifact Signup and view all the answers

________ forms when dust carrying microbes sticks to the outside of a rock and forms an iron oxide-rich covering.

Desert varnish Signup and view all the answers

The majority of erosion in the desert is due to ________.

water Signup and view all the answers

Fine-grained sediment, such as dust and silt, is transported by wind in ________.

suspension Signup and view all the answers

Physical weathering produces piles of broken rocks called ________.

talus Signup and view all the answers

Physical weathering is more prevalent in the desert due to the ________.

lack of water for chemical reactions Signup and view all the answers

Compared with humid climates, the rates of chemical weathering in deserts are ________.

much slower Signup and view all the answers

The saltation of sand involves ________.

grains traveling short distances (approximately 1 m) in the air Signup and view all the answers

Desert varnish consists of ________.

dust deposits affected by microorganisms Signup and view all the answers

In the figure below, the sand grains are being transported by ________.

saltation Signup and view all the answers

Which of the following is an example of wind erosion?

large piles of sand that move across the desert floor Signup and view all the answers

Which of the following images is the result of chemical erosion?

Image B Signup and view all the answers

What is the largest particle that can be carried as part of the suspended load during wind erosion?

silt Signup and view all the answers

Most of the erosion in desert environments is caused by ________.

water Signup and view all the answers

Why is chemical weathering relatively rare in deserts?

Chemical weathering most often involves reaction with water, which is rare in deserts. Signup and view all the answers

The process of lowering the surface of the land by wind erosion is known as ________.

deflation Signup and view all the answers

Piles of sand that form simple, wave-like shapes are called ________ dunes.

transverse Signup and view all the answers

An apron-shaped pile of alluvium that forms at the mouth of a canyon is known as a(n) ________.

alluvian fan Signup and view all the answers

Calcrete (caliche) forms in a desert climate through the dissolution and the reprecipitation of ________ during and after rainstorms.

calcite Signup and view all the answers

Iron-rich, well-oxidized strata will be ________.

dark red Signup and view all the answers

Mesas, buttes, and chimneys are all the result of ________.

cliff retreat Signup and view all the answers

When fine-grained sediment is blown away as shown in the figure below, the coarser sediment left behind is known as ________.

a lag deposit Signup and view all the answers

Areas with relatively scarce sand and constantly shifting winds will develop ________ dunes.

star Signup and view all the answers

The image below is of a ________ dune.

transverse Signup and view all the answers

Imagine that you come across a flat, thick layer of rock salt in an outcrop. What can you determine about the sedimentary environment in which it was formed?

It was arid. Signup and view all the answers

Which of the following images is the result of sediment deposited at the mouth of a canyon?

Image C Signup and view all the answers

The geometry of sand dunes is NOT strongly influenced by the ________.

timing of the monsoon season Signup and view all the answers

How do chimneys (also called hoodoos) and yardangs differ?

Chimneys are remnants of physical erosion, whereas yardangs are remnants of wind erosion. Signup and view all the answers

________ results from the transformation of a once-fertile area to an arid desert.

Desertification Signup and view all the answers

Which of the following would NOT be a cause of desertification?

rainfall Signup and view all the answers

Which of the following human activities can cause desertification?

diversion of water from an area Signup and view all the answers

Desertification may also be responsible for which of the following far-reaching consequences?

destruction of coral reefs Signup and view all the answers

Conversion of productive land to desert is known as ________.

desertification Signup and view all the answers

The Dust Bowl event in 1933 resulted from which natural event?

long-term drought Signup and view all the answers

The desertification of the Sahel region in Africa was the result of ________.

removal of grasses from the soil Signup and view all the answers

Which of the following hazards could lead to desertification?

climate change Signup and view all the answers

Study Notes

Rain-shadow Deserts

Rain-shadow deserts develop on the leeward side of mountain ranges due to orographic lift.

Types of Deserts

Deserts can be classified by temperature; they are not limited to hot areas but can be arid in polar regions as well.

Temperature Records

The highest recorded temperature on Earth was in the low-latitude, low-elevation desert located in Libya.

Desert Coverage

Deserts cover approximately 25% of Earth's surface, highlighting their significant presence.

Subtropical Deserts

Subtropical deserts form when air masses dry out after crossing equatorial rainforests.

Desert Qualification

To qualify as a desert, an area must be arid with less than 15% vegetation cover.

Climate Characteristics

The desert climate associated with rain-shadow effects is found on the leeward side of mountain ranges.

Coastal Deserts

Coastal deserts can form due to cold ocean currents that cool and dry the air.

Gobi Desert

The Gobi Desert is caused by air masses losing moisture as they traverse dry land.

Characteristics of Western US Deserts

Western US deserts primarily arise from being situated within rain-shadows.

Erosion in Deserts

Most desert erosion is due to water, contradicting the notion that wind is the sole factor.

Sediment Transport

Fine-grained sediment is transported through the process known as suspension.

Physical Weathering

Physical weathering in deserts occurs due to high heat and lack of moisture, impacting the rock’s ability to retain heat.

Chemical Weathering

Chemical weathering is rare in deserts as it predominantly involves reactions with water, which is scarce.

Types of Weathering Rates

Chemical weathering occurs at a much slower rate in deserts compared to humid environments due to low moisture levels.

Sand Transportation

Saltation refers to the process where grains travel short distances (about 1 meter) through the air, aided by wind.

Desert Varnish

Desert varnish consists of dust deposits affected by microorganisms and is formed over time.

Wind Erosion

Wind erosion in deserts leads to the formation of distinct features like ventifacts and yardangs.

Dune Types

Transverse dunes are characterized by simple, wave-like shapes formed by wind patterns.

Sedimentary Environments

The presence of a thick layer of rock salt indicates that the sedimentary environment was arid.

Desertification

Desertification refers to the transformation of previously fertile land into desert, often due to human activities and natural events.

Causes of Desertification

Key contributors to desertification include overpopulation, overgrazing, and diversion of water resources, while increased rainfall can mitigate it.

Long-term Drought

The Dust Bowl of 1933 was primarily caused by long-term drought exacerbated by poor agricultural practices.

Sahel Region Desertification

The desertification in the Sahel region was influenced by the removal of grasses from the soil due to overpopulation and land practices.

Climate Change Impacts

Climate change poses a significant risk for increased desertification globally.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Test your knowledge on key terms related to deserts with these flashcards from Geography Chapter 17. Each card presents a word along with multiple-choice options to enhance your understanding of the subject. Perfect for quick review and memorization.