INVESTIGATING EARTH's OCEANS the first rulers of the world Oceanus per Sonified the river that the Greeks believed encircled the flat Earth The oceans influenced the formation of Earth's land surface as it is known today Deadliest A Roman mosaic from 3rd century AD depicts the god Oceanus DEA G Dagli Orti Getty Images 12
THE WORLD OCEAN During several periods of Earth s history large parts of North America were covered by the ocean Most of the limestone sandstone and shale on land was deposited as sediment on the bottom of ancient shallow seas Chalk such as that found in England and the U S states of Texas and Kansas was formed on seabeds from the shells of sea creatures The oceans also affect climate Water has a high capacity for storing heat It warms more slowly than land and it also cools more slowly Thus the coasts of the continents have cooler summers and warmer winters than the inland areas One example of this moderating effect is the Gulf Stream a warm current in the North Atlantic flowing from Gulf of Mexico north east along United States coast to Massachusetts and then eastward toward Europe The oceans are also the birthplace of storms that affect cli mate throughout the world OCEANOGRAPHIC RESEARCH The scientific study of all aspects of the oceans is called oceanography The major branches of this study are concerned with the physical nature of the oceans their chemical and mineral constituents the great variety of living things that inhabit 13
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THE WORLD OCEAN the oceans and the geological structure of the ocean floor Oceanography is also concerned with the technical and economic potentials of the oceans Oceanographic research is veryexpensive Usually it is undertaken by governmen tal and international organizations or by large universities The first purely scien tific oceanographic expedition ranks as one of the greatest ever undertaken From 1872 to 1876 the British research vessel HMS Challenger cruised around the world The famous 50 volume report of the Challenger Expedition formed the basis of the modern science of Oceanography Much research was carried on during World War II Since then there has been more exploration of the ocean than in all previous history Many large organizations study the oceans The Intergovernmental Oceanog raphic Commission of the United Nations Educational Scientific and Cultural Organization UNESCO encourages inter national cooperation in ocean research and sponsors numerous long term expeditions Sailors examine a haul aboard the HMS Challenger during its scientific voyage around the world Time Life Pictures Getty Images 15
