Ch. 24. 1 - Properties of Ocean Water

What is the most abundant element in sea salts?

chlorine

What is the range of salinity in ocean water?

3.3% to 3.6%

thermocline

a layer in a body of water in which water temperature drops with increased depth faster than it does in other layers

Suppose that global temperatures increase. How could this change affect the ability of the ocean to absorb CO2?

An increase in global temperatures would warm the ocean. Warm water can dissolve less gas than cold water can. Therefore, if global temperatures increase, the ocean would absorb CO2 less easily.

How does the density of ocean water control the movement of deep ocean currents?

Cold, dense water at the poles sinks. This water flows under warm water to the equator as deep ocean currents.

salinity

a measure of the amount of dissolved salts in a given amount of liquid

Why is the ocean called a carbon sink?

It traps large amounts of dissolved carbon dioxide.

What is ocean water made up of?

Most of ocean water is pure water. About 3.5% of ocean water is dissolved solids, such as chlorine and sodium. Ocean water also contains dissolved gases, such as nitrogen and oxygen.

Why does ocean water appear to be blue?

Ocean water absorbs white light, which is made up of all the colors of light. It reflects only blue light. As a result, the ocean appears blue.

How do evaporation rates affect salinity?

Salinity will increase if the evaporation rate is higher than the precipitation rate.

Why would surface water in the North Atlantic Ocean probably have more dissolved gases than surface water in the Caribbean Sea?

The North Atlantic has colder water, so it can dissolve and hold more gases.

How would a decrease in phytoplankton affect other ocean organisms?

The organisms would have less to eat, and some could die.

Why does sea ice form in polar oceans?

The surface temperature in polar oceans drops to the freezing point.

Why does the thermocline form in ocean water?

The warm surface water does not mix with the deep, cold water.

What is one way scientists measure salinity?

They measure how easily electricity moves through water.

How does water temperature affect the ability of ocean water to dissolve gases?

Water at low temperatures dissolves gases more easily than water at higher temperatures.

pack ice

a floating layer of sea ice that completely covers an area of the ocean surface

What are the two main gases dissolved in ocean water?

nitrogen and oxygen

What factors affect ocean temperature?

solar energy, water movement, depth, location

Which ocean has a higher average salinity—the Pacific Ocean or the Atlantic Ocean?

the Atlantic Ocean

density

the ratio of the mass of a substance to the volume of the substance; commonly expressed as grams per cubic centimeter for solids and liquids and as grams per liter for gases

In which zone does temperature decrease most slowly as depth increases?

the surface layer

Why is ocean water denser than fresh water?

Ocean water has more dissolved solids than fresh water has. These solids increase the mass and density of the ocean water.

Why does ocean water generally sink near the poles?

Ocean water is coldest at the poles, and cold water is denser than warm water. The high density of the cold water near the poles causes it to sink.

What is salinity?

a measure of how much salt is in a liquid

What two factors affect the density of ocean water?

salinity and temperature

Name three properties of ocean water.

salinity, density, color