Ocean FormationHow did the oceans form??

Formation of the OceanEarth is

approximately 4.6 Billion Years Old

Oceans formed 2 possible ways:CometsVolcanism

CometsComets hit the Earth and

released water The water filled the ocean

basins over geologic time

VolcanismVolcanoes release

Water Vapor, Carbon Dioxide and other gases

Water vapor condensed to form water droplets that formed the oceans

Chemical Properties of Seawater96.5% Water3.5% Dissolved

saltsNaCl is most

abundant

SalinityMeasure of the

amount of dissolved salts in seawater

Expressed in ppt (Parts per thousand) 35 ppt

How Does Water Become Salty?

Volcanic gases contain chlorine and sulfur dioxide which dissolve into water

Weathering of rocks and minerals

Salt RemovalSea SprayEvaporite Formation

Water evaporates and salt is left behind

DesalinationProcess that turns saltwater (saline) into

potable (drinkable) freshwater

Common Methods of Desalination:DistillationReverse Osmosis

DistillationSaltwater is heated

to boiling point and creates water vapor

The heated water vapor is cooled and condensed as freshwater

Reverse OsmosisSeawater pressed through semi permeable

membrane that allows water, not NaCl to pass through

Why would we want to remove salt?Humans need freshwater to surviveOf the 3% of freshwater, most is unavailable

to us! (glaciers)In case of drought conditions, water would

still be available

Environmental ConcernsLoss of Habitat for organisms that live in the

area where the water is taken fromWaste (salt) disposal

Higher concentrations of salt being added back to an environment that is not adapted to those conditions

Costs Money and uses EnergyGreenhouse gas emissions from distillation

plants