Deep Ocean currents

What drives deep-water currents in the ocean?

Density differences in water.

How does temperature affect the density of ocean water?

Warm water is less dense than cold water because warmer molecules take up more space.

What is salinity and how does it influence water density?

Salinity is the amount of salt in water; higher salinity increases density.

How is salinity measured?

By finding the electrical conductivity of water or by evaporating water samples and weighing the remaining salt.

What is the Practical Salinity Unit (PSU)?

A unit used to express salinity, where 1 PSU is equivalent to 1g/kg or 1 part per thousand.

What factors can affect salinity levels in the ocean?

Precipitation, evaporation, freezing, melting, and freshwater runoff.

What happens to salinity near the equator?

Salinity is average (34 ~ 35 PSU) due to high precipitation and evaporation.

What salinity levels are found at 30°N and S latitudes?

High surface salinity (36 ~ 37 PSU) due to higher evaporation than precipitation.

What occurs at 60°N and S latitudes regarding salinity?

Lower salinity (33 ~ 34 PSU) because precipitation exceeds evaporation.

What is the salinity range at high latitudes (60° to 90° N and S)?

Low surface salinities (32 ~ 33 PSU) due to little evaporation and more melting.

What is Thermohaline Circulation?

A deep-water current driven by both temperature and salinity affecting ocean water density.

Which factor is more influential in determining ocean water density?

Temperature is the more influential factor compared to salinity.

Why does the Atlantic Ocean have higher salinities than the Pacific Ocean?

The Atlantic has a smaller surface area, leading to easier evaporation.

What is upwelling in ocean currents?

The process where cold water is forced upwards, often creating nutrient-rich areas.

What effect does upwelling have on marine life?

It increases the amount of algae, which boosts the entire marine food web.

How does the angle of insolation affect ocean water temperature?

Higher latitudes have lower angles of insolation, resulting in colder water.

What seasonal changes influence salinity in polar regions?

Ice formation in winter and melting in summer affect salinity levels.

What is the relationship between evaporation and precipitation at 30°N and S?

Evaporation exceeds precipitation, leading to higher salinity.

What is the significance of the isohaline map in oceanography?

It helps visualize the distribution of salinity in different ocean regions.

Lexington is located at about 41 degrees N of the equator. While on any given day winds can come from any direction, on average, the wind in Lexington most likely comes from the

West

Which currents in the gyre are warm?

The western current (on the left side of the gyre)