Presentation on theme: "Earth and Space Science"— Presentation transcript:
1 Earth and Space Science Ocean CurrentsEarth and Space Science
2 Seawater Temperature, Salinity and Density Ocean waves carry matter and energyThis thermal energy can be transferred to the air, and to the land.There are multiple layers in the oceanThere are multiple densities of water in the oceanThe ocean’s salinity is not uniform
3 CurrentsWater in oceans can sink, rise, and flow horizontally
10 B. Density is determined by 2 factors Cold water is more dense and sinksWarm water is less dense and stays at the surface
11 B. Density is determined by 2 factors 2. SalinityConcentration of dissolved salts in the seawaterExpressed as parts per thousandApproximately 35 parts per thousand (35 g salts per 1000 g water)Higher salinity = higher density
13 B. Density is determined by 2 factors Surface water can change in density by changing salinity due to excess rain or increased evaporation or where rivers enter the ocean
14 Temperature and salinity vary II. Water MassesThe ocean is a single body of water but is not the same everywhereTemperature and salinity varyfrom place to placeWater Mass – a large region of water within the ocean that is about the same temperature and salinity
25 B. Gyres help transportenergy and matter fromlow latitudes to thehigher latitudes.
26 C. Caused by blowing winds near the Equator 1 C. Caused by blowing winds near the Equator 1. Tradewinds/Easterlies – at low latitudes/tropics Blow East to West
27 2. Prevailing Westerlies – in mid-latitudes Blow West to East
28 D. Eckman Drift – horizontal movement of water resulting from the balance of the Coriolis effect and wind stress
29 1. Causes water to move at an angle to the right of the general wind direction (90o) 2. Causes a “mound of water” which balances out the Eckman Drift
30 E. UpwellingStrong upward movement of water from the deep to the surface
31 E. Upwelling 1. As water moves away from the coastline due to the Eckman Drift, more water flows up toreplace it from deeper in the ocean.2. The upward movement brings nutrient rich deep water to shallow areas for animals and plants to use
34 E. Upwelling3. Nutrients come from the “rain” of dead organisms from the warmer surface layer4. Deep circulation moves the nutrients around, and then upwelling generally moves the nutrients to the eastern sides of ocean basins.5. Most fisheries are supported by this upwelling of nutrients.
35 F. DownwellingDownward motion of surface water to the deep ocean
Your consent to our cookies if you continue to use this website.