PLANET EARTH: ARID REGIONS
Physical Weathering Examples -_______________ -_______________
-Abrasion can weather rock -Moisture can weather rock
Examples of subtropical deserts -_______________ -_______________ -_______________
-Mojave -Chihuahuan -Sahara
What are the two layers under desert pavement? -__________________ -__________________
-Soil -Old Alluvium
Five types of Deserts -_____________ -_____________ -_____________ -_____________ -_____________
-Subtropical deserts -Rain- shadow deserts -Coastal deserts -Continental interiors -Polar deserts
How do human activities cause desertification? -__________________ -__________________ -__________________
-expansion and intensive use of agricultural lands -poor irrigation practices -deforestation
desert pavement is a surface layer of closely packed or cemented -_______________ -________________ -________________
-pebbles -gravel -rock fragments
desert
A barren area of landscape where little precipitation occurs and, consequently, living conditions are hostile for plant and animal life.
subtropical desert
A biome prevailing at approximately 30° N and 30° S, with hot temperatures, extremely dry conditions, and sparse vegetation.
Convection Cell
A circular pattern of air rising, air sinking, and wind.
desert varnish
A dark, rusty-brown coating of iron oxide and magnesium oxide that accumulates on the surface of the rock.
rain shadow desert
A dry area on the lee side of a mountain range.
Dune
A hill of sand piled up by the wind
desert pavement
A layer of coarse pebbles and gravel created when wind removed the finer material.
Alluvial Fan
A wide, sloping, fan-shaped deposit of sediment formed where a stream leaves a mountain range
continental interior
Areas in the continental interiors, far from source of moisture where hot summers and cold winters prevail.
Eventually a Mesa can end up as a _______________ or a _________________
Butte Chimeny
The last slide is an example of the ______________________
The Law of Superposition
polar desert
a high-latitude region that receives very little precipitation
Hadley Cell
a system of vertical and horizontal air circulation predominating in tropical and subtropical regions and creating major weather patterns.
As time increases, _______________ increase
amount of erosion
With desert pavement, the light things are ____________________
blown away
In regards to erosion in deserts, fine sand grains are removed leaving behind coarser material. The process is called deflation and the material left behind forms a __________________
desert pavement.
playa
dried up lake bed
The backside of the mountain is ________________
dry desert
Mesa
flat-topped mountain or hill. It is a wide, flat, elevated landform with steep sides.
Desertification facilitates ____________________ that cross entire ocean basins and carry __________________ and __________________
large dust storms dangerous chemicals and disease organisms.
Subtropical: At 0* at earth's equator, ___________ rises and ____________ descends
moist air dry air
dunes may _______________ over time and may ________________ over time
move change form
Polar deserts have a _______________ if there is not enough snow
net loss of ice
Polar deserts have no __________, just _________
no rain, just snow
coastal desert
occur in cool to warm areas along the coast. They have cool winters and long, warm summers.
deserts are very ______________ and ______________ environments
sensitive and fragile
These unsustainable land uses place enormous pressure on the land by altering its ________________ and _________________.
soil chemistry and hydrology
Desert landscapes may consist of __________ on the top and ______________ on the sides
strong rock rubble
Lag Deposit
the coarse sediment left behind in a desert after wind erosion removes the finer sediment
Coastal Deserts come in contact with ____________________
warm and cold currents
In deserts, the primary agent of erosion is ____________ the secondary agent of erosion is _____________
water wind