3 Seawater Properties Free Online FlashCards

What makes up most of seawater by mass?

About 96.5% of seawater by mass is water; most of the remainder is dissolved salts.

What does salinity measure?

Salinity is the amount of dissolved salts in water.

What is the average open-ocean salinity?

Average open-ocean salinity is about 35 grams of salts per kilogram of seawater.

How does evaporation affect seawater salinity?

Evaporation removes water but leaves salts behind, so salinity increases.

What happens to nearby seawater when sea ice forms?

When sea ice forms, much of the salt is excluded from the ice, making nearby seawater saltier.

What influences ocean surface temperature?

Sunlight heats the ocean surface, whose temperature varies with latitude, season, and weather.

How do temperature and salinity affect seawater density?

Cooler seawater is generally denser than warmer seawater, and saltier seawater is denser than fresher seawater.

How does increasing pressure affect seawater density?

Pressure increases with depth and slightly increases seawater density, especially at great depth.

How does seawater move in response to density differences?

Water denser than its surroundings tends to sink; less-dense water tends to rise.

What is ocean stratification?

Stratification is the layering of ocean water due to differences in properties such as temperature, salinity, and density.

What do thermocline, halocline, and pycnocline describe?

A thermocline has a rapid temperature change, a halocline a rapid salinity change, and a pycnocline a strong vertical density change.

What tends to lower surface salinity?

Rainfall, river inflow, and melting ice add freshwater and generally lower surface salinity.