1. The Conveyer Belt EEn. 2.3.1  Ocean circulation travels from the Atlantic Ocean through the Indian & Pacific oceans & back again  Warm water in upper layers of ocean flows toward poles  When water reaches the poles, temp drops & salinity increases, making it more dense.  It returns to the equator as cold, deep water, eventual upwelling completes the circuit  Moves around the globe influencing global climate by converting warm water to cold water & releasing heat to the atmosphere 2.3.1Explain ocean currents develop and move1

2. Density Currents: Density Currents: –Vertical currents of ocean water result from density differences among water masses. –Denser water sinks & slowly spreads out –Causes by  decrease in temperature  An increase in salinity –Evaporation Formation of sea ice  A decrease in salinity –Precipitation –Runoff from land –Icebergs melting –Sea ice melting 2.3.1Explain ocean currents develop and move2

3.  This cross section of Atlantic Ocean shows the deep-water circulation of water masses formed by density currents  deep-ocean density currents begins in high latitudes at the surface  When this water becomes dense, it sinks, initiating deep-ocean density currents Oceanographers can track the movements of density currents in the deep ocean by the temp, salinity, density of water mass & can map the slow circulation of water mass through the ocean Ocean Density & Currents 2.3.1Explain ocean currents develop and move3

4. Ocean Surface Currents  Ocean circulation is organized into five major gyres, or circular current systems. –North Pacific Gyre –South Pacific Gyre –North Atlantic Gyre –South Atlantic Gyre –Indian Ocean Gyre  Factors Influencing Surface Currents –Wind –Coriolis effect – deflection due to Earth’s rotation ( Rt. In the NH; Lt. in the SH) 2.3.1Explain ocean currents develop and move4

5. Ocean Currents and Climate  Color satellite image shows temperatures in the Gulf Stream  Warm water of the Gulf shown in red/orange  Colder water shown in green, blue, and purple  When currents from low-latitude regions move into higher latitudes, they transfer heat from warmer to colder areas on Earth  As cold water currents travel toward the equator, they help moderate the warm temperatures of adjacent land areas  http://app.discoveryeducation.com/pl ayer/view/assetGuid/9F61F275- AD4C-4FBF-9E00-8CA51F884A4B http://app.discoveryeducation.com/pl ayer/view/assetGuid/9F61F275- AD4C-4FBF-9E00-8CA51F884A4B http://app.discoveryeducation.com/pl ayer/view/assetGuid/9F61F275- AD4C-4FBF-9E00-8CA51F884A4B 2.3.1Explain ocean currents develop and move5