1. Wind Erosion Wind can erode both soil and rocks.
There are areas that are more vulnerable to wind erosion.
These areas have very low plant cover.
Because there are no roots to hold the soil in place the wind is able remove soil and other fine particles.
The process by which material is moved is called saltation.

2. Saltation
Saltation is the skipping and bouncing movement of sand size particles in the wind.
Particles can collide with each other as the wind blows.
Other particles will “creep” forward or be thrown into the air

3. Saltation

4. Deflation The removal of fine sediment is called deflation.
During deflation the wind removes the sediment or soil leaving behind rock fragments
Deflation may cause “desert pavement” a surface consisting of pebbles and rocks.
Deflation hollow is a depression in the land where there are no plants to hold the soil

5. Deflation

6. Abrasion
Abrasion is the grinding and wearing away of rock surfaces through the mechanical action of other rocks or sand.
Abrasion commonly happens in areas where there is loose sand and strong winds.
The blowing of millions of sharp sand grains helps erode, smooth, and polish rocks.

7. Wind deposited material
Much like water wind carries sediment and eventually drops all of its materials as well.
The amount and size of the materials the wind can carry depends on the wind speed
The faster the wind the more material it can carry.
As wind speed slows the heavier material is deposited first.

8. loess
Wind can deposit fine grained material large collections of this material is called loess.
Fine grained material can be carried higher and further from its original source.
Loess feels like baby powder
Many of the loess structures are from the ice age

9. Dunes The mounds of wind deposited sand
When wind hits a plant or rock the wind slows down
As the wind slows the heavier material is dropped
The deposited material creates a bigger obstacle causing the wind to slow down further and drop more material

10. Dunes Cont. Dunes move in the direction of the wind
Wind condition influences the size and shape of dunes
Dunes have a gently sloped side and a steep side
The steep side of a dune is called a slip face

11. Dunes

12. Erosion and deposition by ice
Can you imagine an ice cube the size of a football field? Glaciers can be bigger than that.
GLACIERS are enormous masses of moving ice.
Glaciers a able to erode move and deposit large amounts of rock material

13. How do Glaciers Form?
A glacier begins when snow doesn't completely melt away during the summer. Each winter new snow falls on top of the old snow. Thick layers of snow are gradually compressed into glacial ice.
In polar regions and high elevations snow piles up and the weight of the deep pack snow turns to ice crystals.
There are two main types of glaciers Alpine and Continental glaciers

14. Glacier Formation
Glaciers are made up of more than just ice and snow. They contain water, rocks and sediments. This can make the ice look very dirty.
A glacier might look like a solid block of ice, but it is actually moving very slowly. The glacier moves because pressure from the weight of the overlying ice causes it to deform and flow. Meltwater at the bottom of the glacier helps it to glide over the landscape.

15. Alpine Glaciers
Alpine glaciers begin high up in the mountains in bowl-shaped hollows called cirques. As the glacier grows, the ice slowly flows out of the cirque and into a valley. Several cirque glaciers can join together to form a single valley glacier.
A cirque is a bowl-shaped hollow found high up on the side of a mountain.

16. Valley Glaciers
One of the most common alpine glacier is a valley glacier.
When several cirque glaciers merge into a single valley or piedmont glacier the ice has a striped appearance.

17. Valley Glaciers

18. Continental Glaciers
Continental glaciers are continuous masses of ice that are much larger than alpine glaciers. Small continental glaciers are called ice fields. Big continental glaciers are called ice sheets. Greenland and Antarctica are almost entirely covered with ice sheets that are up to 3500 m (11 500 ft.) thick.
Continental glaciers are much larger than alpine glaciers but it can be more difficult to see how they have eroded the landscape.

19. Continental Glaciers
Sediments are scraped away then the exposed bedrock is carved and polished by the passing ice. This happens much faster if there are lots of rocks and sand poking out from the bottom of the ice.
Continental glaciers bury the landscape and only the highest mountain peaks poke out through the ice surface. These mountain peaks are called nunataks.
Domed and roughly circular ice caps are bigger than ice fields but smaller than ice sheets. Smaller outlet glaciers can flow from ice caps.

20. Continental Glaciers
Ice cap

21. Glacial landforms
When a glacier melts, all of the rock, sand and mud that it was carrying gets left behind. Geologists call this mixture of sediment till.
Piles and ridges of sediment deposited at the edges and front of glaciers are called moraines.