Earth s Oceans & Ocean Floor Date: Feelin Blue What are Earth s five main oceans? Almost of Earth is covered by water. On a map, the continents appear as huge islands surrounded by a vast global ocean. Earth s global ocean is divided into main oceans. In order of size, they are the Pacific Ocean, Atlantic Ocean, Indian Ocean, Southern Ocean, and Arctic Ocean. dissolved salts. What are some characteristics of ocean water? The characteristics of ocean water include, or the amount and type of Chemical characteristics also include the amount and type of in the seawater. The characteristics of ocean water include and. The overall of seawater is about percent.
2 Dissolved come from flowing on or under Earth s, and from underwater and. The salinity of seawater has relatively steady, but it from place to place depending on the entry of freshwater streams, precipitation, and rate of evaporation. The ocean has temperature layers by depth. The layer, or zone, is the layer. In the next layer, the, water temperature with increased depth faster than it does in other layers. The zone is the layer and the. By, water is warmest near the and coldest near the. By, water is warmest in summer and coldest in winter. is a measure of the mass of a substance divided by its volume. The density of ocean water depends on temperature and salinity. Salt water is than fresh water because salt water contains a larger amount of. affects the density of ocean water more than salinity does. Cold water is denser than warm water. Seeing the Sea How is the ocean floor studied? To learn about the ocean floor, scientists use such as, drills, underwater exploration vessels, and
3., which stands for sound navigation and ranging, uses sound waves to measure distances. Sonar data can be used to make of the ocean floor. How is the ocean floor studied? What is this ship doing and why? can measure variations in the height of the ocean s surface. The ocean floor s features can the height of the water above them. To explore the oceans, scientists use underwater vessels, some of which have and researchers. Other vessels are operated. Using equipment on large ships, scientists can drill and collect cores, or long tubes of rock and sediment, from the sea floor. In Deep Water What are the two main regions of the ocean floor? The main regions of the ocean floor are the continental margin and the deep-ocean basin. The is the edge of the continent that is covered by the ocean. The continental margin is into the continental, the continental, and the continental. The begins at the end of the continental margin and extends under the deepest parts of the ocean.
4 The deep-ocean basin includes narrow and flat, smooth. What are the features of the ocean floor? A long, undersea mountain chain that forms along the floor of the ocean is called a. Mid-ocean ridges occur at the of Earth s plates, where plates move from each other. This creates a in the ocean floor called a, allowing hot to move upward through the rift and cool to new rock. The large, flat, almost level area of the deep- ocean basin is called the. This area is covered with layers of fine. A long, narrow depression in the deep-ocean basin is called an. It forms where one tectonic plate another plate. Mariana Trench and are common in and along zones. Submerged volcanic mountains on the ocean floor are called. They may form at tectonic plate boundaries and also far from plate boundaries over places called. If a seamount grows sea level, it becomes a.
5 Ocean Currents Going with the Flow What are ocean currents? are streamlike movements of water in the ocean. currents are ocean currents that occur at or near the surface of the ocean, caused by wind. The Stream is one of the surface currents on Earth. What affects surface currents? Surface currents are by continental deflections, the effect, and winds. When surface currents meet, they are and change. The deflection of moving objects from a straight path due to Earth s rotation is called the. In the Hemisphere, currents are to the. In the Hemisphere, currents are to the. winds can push ocean water across Earth s surface to create surface currents. What powers surface currents? The major source of that powers surface currents is the. The sun air near the equator more than it heats air at other
6 latitudes. As a result, there are differences in in the atmosphere. form as a result of differences in air pressure and create surface currents. Current Events How do deep currents form? currents are movements of ocean water far below the surface. They are caused by differences in water density. is the amount of matter in a given space or volume. and temperature cause differing ocean water densities. How do deep currents form? Salinity is a of the amount of or solids in a liquid. salinity makes water dense. water is than water. Dense water sinks and can form deep water currents that flow along the ocean floor or on another layer of denser water. What are convection currents? currents in the ocean are the movement of water that results from density differences. Convection currents can be,, or cyclical. How do convection currents transfer energy? Water at the ocean s surface energy from the sun, and surface currents carry this energy to colder regions. As water reaches a colder region, it cools, becomes, and. As warm surface water moves away, cold water rises to the surface. The cold water absorbs the sun s energy, and the cycle continues. That s Swell
7 What is upwelling? is the process by which winds blow warm water away from a shore, allowing cool, nutrient-rich water to rise to the surface. Upwelling the that support the of phytoplankton and zooplankton. These tiny organisms are food for larger organisms, such as fish and seabirds. Hitching a Ride! Ocean currents can various living organisms to different parts of the world. Turtles, coconuts, and phytoplankton all ride the ocean s surface currents. Traveling the World What do ocean currents transport? currents in the ocean transport in the form of. currents can energy into the atmosphere, making currents an important influence on climate. Ocean water also dissolved solids, including nutrients, and dissolved gases that support the growth of many marine organisms.
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