All Desert

What are barchan dunes?

Crescent-shaped dunes formed when sand supply is limited.

What are transverse dunes?

Large ridges of sand perpendicular to the wind direction.

What are longitudinal dunes?

Long, narrow ridges of sand parallel to the prevailing wind.

What are parabolic dunes?

U-shaped dunes with a vegetation-stabilized windward side.

What are star dunes?

Dunes formed by multi-directional winds, creating star-like shapes.

What are the main causes of desertification?

• Plate Tectonics & Continental Drift

• Milankovitch Cycles

• Greenhouse Gas Fluctuations

• Extraterrestrial Events

• Mountain Barriers that block moist air

• Human Water Use in dry climates

What causes desert climates?

Persistent year-round dryness, often due to geographical location.

Where are most deserts located?

Subtropical regions and on the leeward sides of mountains.

What type of weathering is most common in deserts?

Mechanical weathering caused by water, including brief but intense rainfall.

What are the main effects of wind erosion (eolian activity) in deserts?

• Produces blowouts and desert pavement.

• Creates loess (silty deposits) and dunes (bedload deposits).

What is an alluvial fan?

A fan-shaped deposit of sediment formed by an ephemeral stream.

What is a playa lake?

A temporary lake that forms in low desert areas, evaporating in dry seasons.

What is a bajada?

A broad slope of debris formed by the merging of alluvial fans.

What is an inselberg?

An isolated mountain or rock hill that rises above the surrounding desert.

What is loess?

Fine, silty sediment deposited by wind.

What are sand dunes?

Mounds or ridges of sand formed by wind deposition.