Water Water Everywhere

Water, Water Everywhere (Earth Science Our planet earth is not the same as when it was formed. It has gone through transformation as a part of its evolving process, and this evolution of our planet continues even today. Land and water bodies are the major components of our planet earth. It is to these land and water bodies that we look up to for shelter and means of sustenance. The land bodies and the water bodies are constantly in the state of change or development. Stream Valleys are the result of this constant change or development. Evaluation of stream valleys is an interesting way to understand the change and development that is occurring in land and water bodies. Water on our planet is not present in the water bodies alone, but as water vapour in the atmosphere due to evaporation from the water bodies. This water vapour in the atmosphere precipitates on to the land bodies and runs back into the water bodies. Thus, there is a continuous exchange of water from the water bodies to the atmosphere and on to the land bodies and back to the water bodies. It is this hydrologic cycle or exchange of water that occurs from the ocean to the atmosphere and on to the land bodies, and finally back to the water bodies that is responsible for the creation of Stream Valleys. Evaporation from the water bodies into the atmosphere, precipitation from the atmosphere onto land and infiltration of this precipitated water into the land and the consequences of its return to the water bodies is seen as stream valleys. Precipitated water moves within the land or runs of the land causing erosion in the land. This erosion results in a gap or a space of land that lies between the two water edges at the height of its run off to the oceans or lakes. Thos gap or space of land is the Stream Valley. Water is the best sculptor and the beauty of the stream valley lies in the natural sculpting ability of water as it erodes the land mass over which it runs down to the ocean or lakes. Running water as a natural sculptor demonstrates its versatility by providing us with two types of water valleys. The two types of water valleys are the V-shaped valley and the Wide Valley. It takes imagination to understand the wonder of the natural sculpting ability of water moving over land. Just imagine the ability of large volumes of water rushing over land and the changes that can be brought on to the topography of the land. This is water at its sculpting best. Water is a patient sculptor. The changes in the topography that are seen as the result of the eroding action of water do not happen overnight rather it is a pains-taking process. It is the slow, yet constant natural movement of water over land that causes the changes in the topography of the land. This can be understood when we consider that rocks are a part of the land formations and erosion of rock by water is not an easy process. Instead it has found an easier way to do that. It slowly weakens and erodes the soil around the rock as it constantly passes over the rock and the soil. This soil erosion at the base over time results in the creation of a valley. The base levels of the erosion are classified into ultimate or temporary levels. It is the changes that occur at the base level that are responsible for determining whether the water flow will find new pathways and thereby generate new water systems. The lower the base level the resultant force of water flow will be a sharp edge, resulting in a down cut in the land formation. A raise in the level of water flowing will however result in soil deposition within the system of the flow of water that will lead to a new body of water or the generation of a new water system. It is the combination of all these actions of water that are responsible for the formation of the V-shaped valleys with sharp edges. The gradations in the cutting action of water flow are the reason why two types of valleys are formed. In the narrow V-shaped valley water falls and rapids are a common occurrence. The waterfalls and rapids are the result of the down cutting of the water in the direction of the base level of the rock formation. The Wide Valley is characterised by flat floors at the bottom. Wide Valleys result when water uses its flow energy to cut at the sides increasing the width of its flow and creating a flood plain. From the wide valleys of flood plains it is not uncommon to see the formation of bends called meanders or increased activity leading to the development of short channel segments called cut-offs or oxbow lakes (Tarbuck Lugens, 2010). (Word Count – 823) Literary References Tarbuck, E. J. Lugens, F. K. (2010). Running Water and Ground Water: Summary. Earth Science 10th Ed. Retrieved May 29, 2011, from, http://wps.prenhall.com/esm_tarbuck_escience_10/3/854/218736.cw/index.html