Pacific Ocean covers about a third of the Earth’s surface with an area of 155. 557 million km2 (Pidwirny, 2010). It is even larger than the Earth’s total landmass which is approximately 148.94 million km2. It extends approximately 15,500 km from Bering Sea found in the Arctic region to the northern part of the Circumpolar Ocean at latitude 600S (Bardach, Cotter & Morgan, 2006). It stretches west-east at approximately 19,800 km in the region of 50N latitude from Colombian and Peruvian Coast to Indonesia (Pidwirny, 2010). Its width is about five times the diameter of the Moon.
The depth of the ocean varies although it has an average depth of about 4028-4188 m (Pidwirny, 2010). Its lowest point on Earth is found at Mariana Trench and is about 10,911 m (Pidwirny, 2010). It is presently shrinking as a result of plate tectonics.
Andesite Line is the most distinctive feature of the Pacific Ocean. The line separates the Central Pacific Basin from the partly Submerged Continental (Garrison, 2009).
The ocean has about 25,000 islands which are in excess of the entire number islands in all the oceans across the world (Garrison, 2009). Most of these islands are located in the south of the equator; some of them are partially submerged. However, the ocean is never always peaceful. It experiences lots of tropical storms which destroy the islands. Besides, the lands which border the Pacific Rim have volcanoes which make it prone to earthquakes. It experiences tsunamis which result from underwater earthquakes, and these have sometimes destroyed many islands.
The biggest landmass within this ocean is the Island of New Guinea. New Guinea was part of Australia but broke away in the last glacial period. Most of the ocean’s islands lie in 300 N-300 S, beginning Southeast Asia up to Easter Island. On the other hand, other areas of the Pacific Basin is nearly entirely submerged (Garrison, 2009).
Hotspot volcanism has formed numerous long Seamount Chains in the ocean. According to Garrison (2009) Seamount Chains are series of mountains which have submerged from the Pacific Ocean’s floor. The Pacific Ring of Fire located outside the Andesite Line is the major region of explosive volcanism throughout the world. These mountain chains are formed around hundreds of active volcanoes which lie above several subduction zones. It is only the ocean which is nearly completely enclosed by subduction zones. Inside the ring of Andesite Line, there are submerged volcanic mountains, and these characterize the Pacific Basin (International Hydrographic Organization, 1953).
Deep troughs also form within this ring. Within this region, basaltic lava smoothly flows out of rifts building vast dome-shaped volcanic mountains. Erosion on the summits of the volcanic mountains transforms them into island arcs, clusters, as well as, chains.
The volume of water in the ocean is about 622 million km3 (Garrison, 2009). However, the water-temperature in this ocean varies by latitude. The water freezes polewards but the temperature increases towards the equator up to about 300 C (Garrison, 2009). In addition, salinity of the ocean also varies with latitude. The water is more saline around the mid-latitudes and less saline around the equatorial region. This is majorly attributed to the high precipitation which normally occurs in the equatorial region throughout the year. Salinity is also low in the temperate latitudes especially towards the poles since these areas experience less evaporation.
Reference List
Bardach, J. E., Cotter, C, H., & Morgan, J. R., 2006, Pacific Ocean. Chicago: Encyclopædia Britannica, Inc. Web.
Garrison, T., 2009, Essentials of oceanography, 5th Edition. Cole Publishing. Web.
International Hydrographic Organization, 1953, Limits of oceans and seas, 3rd edition. Monte Carlo, Monaco: International Hydrographic Organization. Web.
Pidwirny, M., 2010, The encyclopedia of the Earth. Web.