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Earth’s Oceans. Chapter 13; Section 1 . Bellringer. Why does coastal water in places with hotter, drier climates typically have a higher salinity than coastal water in places with cooler, more humid climates?. Bellringer.
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Earth’s Oceans Chapter 13; Section 1
Bellringer • Why does coastal water in places with hotter, drier climates typically have a higher salinity than coastal water in places with cooler, more humid climates?
Bellringer • Why does coastal water in places with hotter, drier climates typically have a higher salinity than coastal water in places with cooler, more humid climates? • Coastal water in places with hotter, drier climates has a higher salinity because less fresh water flows into the ocean in drier areas, and because heat increases the evaporation rate.
Earth’s Oceans • Objectives • Describe the history of Earth’s oceans. • Identify the properties of ocean water. • Describe the interactions between the ocean and the atmosphere
1. The history of Earth’s oceans • About 4.5 billion years ago, there were no oceans. • Sometime before 4 billion years ago, water vapor in the atmosphere condensed and fell as rain. • The rain filled the deeper levels of Earth’s surface and the first oceans began to form.
2. The properties of ocean water • Dissolved Gases Nitrogen, oxygen, and carbon dioxide are the main gases dissolved in ocean water. • Solids Sodium chloride, or table salt, is the most abundant dissolved solid in the ocean. Other solids are also found in ocean water.
2. The properties of ocean water • Salinity is a measure of the amount of dissolved solids in a given amount of liquid. • Changes in Salinity Climate and water movement affect salinity. Costal water in cool, humid places has a low salinity. Slow-moving bodies of water have higher salinity than other parts of the ocean do.
2. The properties of ocean water • Compare Hudson Bay & an Egyptian City • Use page 377 to find salinity levels
2. The properties of ocean water • Temperature Zones The temperature of ocean water decreases as depth increases.
2. The properties of ocean water • Surface Temperature Changes Surface-zone temperatures vary with latitude and the time of year. • Surface temperatures range from 1ºC near the poles to about 24 ºC near the equator. • The surface zone is heated more in the summer.
3. The interactions between the ocean and the atmosphere • The water cycle is the continuous movement of water from the ocean to the atmosphere to the land and back to the ocean. • The ocean is an important part of the water cycle because nearly all of Earth’s water is in the ocean.
3. The interactions between the ocean and the atmosphere • The ocean regulates atmospheric temperatures. • A Thermal Exchange The ocean absorbs and releases thermal energy much more slowly than dry land does. • The circulation of warm water causes some coastal lands to have warmer climates than they would have with the currents.
Earth’s Oceans • Objectives • Describe the history of Earth’s oceans. • Identify the properties of ocean water. • Describe the interactions between the ocean and the atmosphere