Erosion

There are several forces which can cause changes in the Earth's surface including volcanoes, earthquakes, tornadoes, floods, and forest fires. One of the slowest types of forces which causes changes in the surface of the Earth is erosion.

Erosion is the wearing away of the land by different forces. These forces, which may also occur during the natural disasters mentioned earlier, include water, wind, and ice. Mountain peaks, valleys, coastlines and other interesting features of the Earth have been formed by erosion.

There are three main types of erosion, but the main cause of erosion on Earth is water. Some erosion can take place rapidly and move soil, rocks, and other natural debris overnight, as during a thunderstorm or flash flood. The two other types of erosion, wind and ice, may take thousands of years.

It seems like water may not be so powerful, however it is one of the most powerful forces on Earth. Water causes erosion several different ways. Rainfall may cause erosion when the drops hit the surface of the Earth almost immediately in some places, which is called splash erosion, or when the rain accumulates and begins to flow and move like a small stream.

Rivers are another cause of water erosion especially over an extended period of time. The movement of the river breaks up particles at the bottom and then carries them downstream. In fact, the Grand Canyon is one famous example of river erosion formed by the Colorado River during a time period of more than 6 million years.

A third cause of water erosion takes place when ocean waves cause a coastline to erode and break apart. The energy and force of the waves causes pieces of rock and the ocean's coastline to break off. This type of erosion can take thousands or millions years as well.

Flooding is another cause of water erosion, but it happens very quickly and it becomes similar to a raging and powerful river moving soil, rocks, and other objects from one place to another. - Large floods can cause erosion to happen very quickly acting like powerful rivers.

Wind is the second type of erosion which mostly takes place in dry areas. Wind can pick up and carry away the particles of soil and dust away. This is called deflation. Another kind of wind erosion is called abrasion, which occurs when the particles the wind carries breaks off pieces of a surface it hits.

Finally, erosion by ice takes place over long periods of time as well. Glaciers made of ice can be like giant rivers of ice that move slowly carving out valleys and changing the shapes of mountains.

Besides the three main types of erosions, living organisms like small animals, insects, and even worms can cause erosion to take place. They help break up the soil during their movements which make it easier for the wind and water to carry away the particles of the Earth's surface.

In addition, the force of gravity can cause changes to mountains or cliffs when there are giant landslides which change the features of its surface. Finally, changes in the temperature and the Sun heating up a rock can cause it to expand and crack. The pieces of the rock break off over time and leads to erosion.

In summary, the three main types of erosion are water, wind, and ice. Water is the most common type of erosion, and all three can cause changes in the Earth's surface in a short period of time or over millions of years.