Erosion is a natural process in which Earth’s surface is worn away by the elements. Rainfall is the major erosive force on Earth’s land surfaces, causing rivers to erode valleys, transport sediment and reshape the landscape, but wind is also an important driver of erosion.
The work of the other two agents of erosion waves and ground water is not controlled by climate. In case of waves it is the location along the interface of litho and hydro sphere coastal region — that will determine the work of waves, whereas the work of ground water is determined more by the lithological character of the region.
If the rocks are permeable and soluble and water is available only then karst topography develops.
The broadest application of the term erosion embraces the general wearing down and molding of all landforms on Earth’s surface, including the weathering of rock in its original position, the transport of weathered material, and erosion caused by wind action and fluvial, marine, and glacial processes.
This broad definition is more correctly called denudation, or degradation, and includes mass-movement processes. A narrow and somewhat limiting definition of erosion excludes the transport of eroded material by natural agencies, but the exclusion of the transport phenomenon makes the distinction between erosion and weathering very vague.
Erosion, therefore, includes the transportation of eroded or weathered material from the point of degradation (such as the side of a mountain or other landform) but not the deposition of material at a new site.
The complementary actions of erosion and deposition or sedimentation operate through the geomorphic processes of wind, moving water, and ice to alter existing landforms and create new landforms.
