This ocean presentation is made for an 8th grade Earth Science class.

1. Ocean Water Earth Science 20.1 8th grade

2. Properties of Ocean Water Dissolved gases Dissolved solids Salinity Temperature Density Color KidsGeo.com. Web. 1 Jul 2011. <http://www.kidsgeo.com/geography-for-kids/0142-ocean-temperatures.php>.

3. Dissolved Gases 2 gases make up atmosphere Nitrogen (N2) & Oxygen (O2) 3 gases dissolved in ocean water O2, N2, CO2, & other trace gases Web. 1 Jul 2011. <http://eesc.columbia.edu/courses/ees/climate/lectures/greenhouse.html>.

4. Dissolved Gases Gases enter at rivers, streams, volcanic eruptions, and organisms living in ocean Web. 1 Jul 2011.http://rst.gsfc.nasa.gov/Sect17/Sect17_4.html.

5. Dissolved Gases Temperature affects amount of gases dissolved Colder water = gases dissolve better, held longer Oceans contain 60 times more carbon than atmosphere Oceans called “carbon sink” – can trap CO2 for hundreds to thousands of years

6. Dissolved Solids Sea salts = 3.5% mass of ocean water Most abundant elements: Chlorine, sodium, magnesium, sulfur, calcium, potassium

7. Dissolved Solids Salt Halite (Sodium & Chlorine) make up 85% of dissolved solids "Dead Sea." Web. 1 Jul 2011. <http://en.wikipedia.org/wiki/File:Dead_Sea-18.jpg>.

8. Dissolved Solids Sources of sea salts: Volcanic eruptions DiscoveryChannel.com. Web. 1 Jul 2011. <http://dsc.discovery.com/news/2008/06/12/underwater-volcano.html>.

9. Dissolved Solids 2. Chemical weathering of land rock Web. 1 Jul 2011. <http://en.wikipedia.org/wiki/File:Abiskorock.JPG>.

10. Dissolved Solids 3. Chemical reactions between sea water & newly formed sea-floor rocks Web. 1 Jul 2011. <http://earthobservatory.nasa.gov/Features/CarbonCycle/page2.php>.

11. Salinity Measure of amount of dissolved salts in a given amount of liquid Average salinity is 3.3% to 3.6%

12. Salinity Factors that change salinity: Rate of evaporation is higher than precipitation, salinity increased Polar waters have high evaporation = high salinity

13. Salinity Can vary greatly depending on location Red Sea has hot & dry climate = high salinity Web. 1 Jul 2011. <http://en.wikipedia.org/wiki/File:Wiki_plot_04.png>.

14. Temperature Varies with depth & location Affected by solar energy Colder near poles Pack ice or floating ice covering top 5 meters of ocean surface Insulates water below & prevents freezing

15. "Climatology SST." Web. 1 Jul 2011. <http://www.nationalatlas.gov/articles/mapping/a_avhrr.html>.

16. Temperature Thermocline- temperature drops with increased depth Water near surface is less dense so heats better but doesn’t mix well with below layers Colder water = more dense Controls the movement of deep ocean currents Holds more dissolved gases than warmer

17. Web. 1 Jul 2011. <http://www.windows2universe.org/earth/Water/temp.html>.

18. Density Mass ÷ volume (love formula) Factors that effect density of ocean water: 1. Salinity (more salt = more dense) 2. Temperature (colder = more dense) Densest water is found in polar regions High salinity = more particles/mL

19. Color Determined by way it absorbs or reflects sunlight Water absorbs most colors of visible light Blue wavelengths are reflected "Vibrant Orange Sunrise Ocean Spray ." Web. 1 Jul 2011. <http://paulbates.com/vibrant-orange-sunrise-ocean-spray-pictures-photos/>. "The Tube." Flickr. Web. 1 Jul 2011. <http://www.flickr.com/photos/mistybushell/2161046983/>.

20. Color Importance Substances or organisms can effect color Ex.) phytoplankton (absorbs red/blue but reflects green) Scientists can determine the health of the ocean Phytoplankton present = healthy ocean

21. Plankton forms off of New Zealand because of abundant food sources. "Plankton bloom off Waiheke Island." Web. 1 Jul 2011. <http://www.teara.govt.nz/en/plankton/1/4>.

22. Textbook Resource Allison, Ph.D., Mead A., Arthur T. DeGaetano, Ph.D., and Jay M. Pasachoff, Ph.D. Earth Science. Austin, Texas: Holt, Rinehart, and Winston, 2008. 26-45, 754-767. Print.