The Deep Blue Sea - Keystone College

The Deep Blue Sea
By JessicaTancordo
Geography
covers 360 million km23 major ocean basinsPacific-180 million km2Atlantic-106 million km2Indian-75 million km2
Structure
Temperature
Sunlight absorbed Kinetic state TemperatureThermal stratification - layering of water by temperature which is a permanent feature of tropical oceansThermocline- a layer of water in which temperature changes rapidly with depthLowest average temp: -1.50CHighest average temp: 270CTemperate zone at 400Latitude- greatest stability at 100 m deep
Current
What does it transport?
What does it do?
nutrientsoxygenheatorganismsGyres – circulation systems move to right of N.Hemisand left of S.HemisUpwelling – wind blows surface water offshore allowing colder water to rise to surface
Moderate climatesfertilizes the surface waters off continentsstimulate photosynthesispromote gene flow through populations
Chemical Conditions
Salinity varies with latitude among seas.Lowest salinities – near equator and above 400N latitudes- precipitation high & evaporation lowHighest salinities – subtropics- precipitation low and evaporation highVaries in small enclosed basinsBaltic and Red SeaOxygen increases at surface and decreases with depth
Biology
Phytoplankton – microscopic photosynthetic organisms that drift with currentZooplankton – small animals that drift with currentRanges from brightly colored organisms inepipelagiczone to bioluminescent organisms in theabyssalpelagiczoneNourished by organic matter provided by photosynthesis at surface.
Biology continued
The deep oceanreferedto as “Biological Desert”¼ total photosynthesis in biosphereProvides substantial amount of global carbon and oxygen.Little that can be harvested economically for direct human consumptions in the open ocean.
Human influences
Whale populationsHarvesting krillDumping of wastesStrandingsOrganismsswallowingand getting caught in trashDecrease in global carbon and oxygenOverfishing affects other populations of others.
Why does the Baltic sea have low salinity?
A) It receives freshwater from temperate and boreal biomesB) it has high precipitationC) it has low evaporationD) all of the above
What isThermocline?
A)a layer of water in which temperature changes rapidly withdepthB)layering of water by temperature which is a permanent feature of tropicaloceans.C) when your thermostat is at yourfathers desired temperature.D) none of the above