Download Ocean Composition

Ocean Composition
Looking at this salinity map, where do you think
the higher salinity areas are?
Salinity – a measure
of the amount of
dissolved solids in a
given amount of liquid.
Top 3 Minerals found
in oceans:
1. Sodium Chloride
(sodium & chlorine)
2. Magnesium
3. Sulfur
Salinity
Where does all that salt come
from?
• Weathering and erosion of
rocks
• Rain and dissolved salts and
minerals that are deposited
in the ocean
What affects salinity? Climate.
Salinity Increases
Coastal or tropical areas
and places with hotter,
drier climates have a
higher salinity
Heat INCREASES the
evaporation rate.
Evaporation removes
water but leaves salts
and other dissolved
solids behind.
Ice forming in the
ocean.
Salinity Decreases
Coastal water in cooler,
more humid places has
a lower salinity.
More fresh water from
streams and rivers run
into the ocean in these
areas
Glaciers melting add
freshwater to the oceans
• What affects salinity? Water Movement
Slower moving areas of water develop higher salinity
• Example: bays, gulfs, seas, open ocean without currents
running through them
Dead Sea = Very Salty – 337 PPT (33.7%)
Baltic Sea = Not Very Salty – 10 PPT (1%)
Salinity, Density, and Temperature
• Salt makes seawater more dense than freshwater
• Oceans with a higher salinity are going to have a higher
density due to the extra salts
• Warmer water = lower density
• Colder water = higher density
*Water that is cold and high in salt will sink to the bottom
of the ocean floor due to its density*