Oceanography/SCI209
June 30, 2014
Professor Barbara Shoemaker
Seawater
The Earth is almost entirely surrounded by seawater. Through evaporation of seawater, water is returned to the Earth through precipitation. The precipitation allows for these salty waters to be filled with drinkable water. The combining forces of freshwater and salt water allow conversion techniques to turn undrinkable water into drinkable water. Such conversions help provide human life with water, one of the most vital resources to sustain life. The objective of this paper is to highlight on the makeup of seawater. It will go into detail to discuss how conversion of seawater into drinkable water is done. It will come to a close with a discussion on the benefits and drawbacks are of these conversion methods.
Chemical Properties of Seawater “Salinity is the total amount of solid material dissolved in water including dissolved gases (because even gases become solids at low enough temperatures) but excluding dissolved organic substances” (Trujillo & Thurman, 2011, p. 139). Essentially, salinity is the difference between seawater and fresh water. There are two water main molecules that makeup seawater: (1) hydrogen and (2) oxygen. Dissolved elements within seawater allow for its salt properties, such substances come from precipitation (rain, snow, etc.), runoffs (streams from precipitation), icebergs melting, and sea ice melting. Seawater is affected by all of these sources in that they add fresh water to the already salty water. 97.2% of the Earth’s surface is composed of seawater (Trujillo & Thurman, 2011). Because of seawater’s salinity, it is undrinkable; however, it can be converted into drinking water in many ways.
Converting Seawater into Drinking Water While there are multiple ways to convert seawater into drinking water, reverse osmosis and distillation are two of the main ways that it is done. “Reverse osmosis is a process where pressure is used
References: Aintablian, X.W. (2014). Water Desalination. Retrieved from http://geography.about.com/od/waterandice/a/Water-Desalination.htm Trujillo, A. P., & Thurman, H. V. (2011). Essentials of oceanography (10th ed.). Boston, MA: Pearson Education. USGS. (2013). Retrieved from http://ga.water.usgs.gov/edu/drinkseawater.html