Warm-Up October 28 The Grand Canyon is an example of a young, middle-aged, or old river? How do you know? Old, the river bed is U-shaped.

How does land change?  MYP Unit Question: How does land change? Environment  Area of Interaction: Environment Caring and Principled  Learner Profile: Caring and Principled Investigate the scientific view of how  Standard: Investigate the scientific view of how the Earth’s surface is formed. the Earth’s surface is formed.

Fastest Wind on Earth  Bell Ringer: Fastest Wind on Earth Today I’m learning about  Learning Target: Today I’m learning about erosion by wind because I erosion by wind because I want to understand how to want to understand how to prevent it. prevent it. Notes – Erosion by Wind  Work Session: Notes – Erosion by Wind Erosion Song  Closing: Erosion Song

On April 12, 1934 at the Mount Washington Observatory in New Hampshire the staff were busy recording wind speeds as an intense storm moved in. Early in the morning wind speeds exceeding 100 MPH were recorded and they continued to increase, it wasn't long till the wind hit speeds of 150 MPH. As the day wore on the winds topped 200 MPH with frequent gusts reaching 220 MPH.

Everything is covered with rime, a kind of ice that forms when water droplets freeze on a cold surface. Then it happened... at 1:21pm on April 12, 1934 a wind gust was recorded at 231 MPH or 372 KM/H, the fastest surface wind speed ever recorded on Earth.

 Wind carries and deposits sediment.  The amount and the size of particles the wind can carry depend on the wind the wind can carry depend on the wind speed speed.  Deserts, coastlines, and areas with little plant coverage are the most little plant coverage are the most affected by wind erosion. affected by wind erosion.  p

In areas where strong winds occur, sand grains knock into one another, some grains bounce up in the air, fall forward, and hit other sand grains. (Abrasion)

Sand dunes form from material deposited by wind.

Example:

leeward windward Example:

Barchan dunes of the Namib Desert Crescent shaped dunes formed from a unidirectional ( one-direction ) wind. Example:

Ripple marks are miniature dunes within a dune (not more than 2 inches tall). Formed by cross winds and appear to be traveling in a different direction than the large dune. Example:

Formed when wind and water weather (erode) softer material first. Example:

Wind carries fine particles that work like a sand blaster (i.e. sand, silt, clay, and ice particles) Example:

Formed in arid environments when wind carries finer, more lightweight particles such as sand away. Large particles are left behind and protect from further erosion. Example:

Yellowish, fine grained silt and clay sized particles formed by glaciers millions of years ago; carried and deposited by wind. Example:

Base of a rock is weathered and eroded more quickly due to sand blasting. Sand grains can only be picked up a couple of feet. Example:

Human activity causes 10 times more erosion of the continental surface of the Earth than all natural processes combined.

Earth's surface involves a balanced process, where new soil forms at about the same rate as it erodes.  If humans are stripping soil at that rate, nature won't be able to keep up.

1. The Earth's human population is growing rapidly. 2. Almost all the land that is capable of producing crops is being used.

Banaue rice terraces in the Philippines

 Crop Rotation George Washington Carver

Cover—definition of Erosion Booklet pages  notes  quality drawings  Labels Standards Check Exit Ticket