How is the density of water affected by heat and salinity? April 8 Learning Log Do you float better in fresh or salty water? Explain in complete sentence why this may be. Essential Question How is the density of water affected by heat and salinity?

How is the density of water affected by heat and salinity? April 9 Learning Log Knowing that salt water is more dense than freshwater, describe the impact that you think this has on the oceans? Think about and then write your thoughts down about what impact temperature has on water in terms of density. Essential Question How is the density of water affected by heat and salinity?

Water Density

Essential Question How is the density of water affected by heat and salinity?

What percentage of the Earth’s surface is covered by oceans? 71% What percent of the Earth’s surface is covered by Oceans?

The ocean covers 71 percent of the Earth's surface and contains 97 percent of the planet's water, yet more than 95 percent of the underwater world remains unexplored. 

Earth has five oceans…… Antarctic or Southern Ocean

Which one is the largest? Covers 30% of surface of the Earth

Which one has the longest distance north to south?

Which one is mostly in the southern hemisphere?

Which one is the smallest? And mostly in the Northern Hemisphere

Seas: are smaller than oceans and are partly or mostly landlocked. Examples: Dead Sea, Black Sea, Mediterranean Sea

Origin of the Oceans Scientists hypothesize that Earth’s water could have originated from two sources: Volcanism Comets Comets occasionally collide with Earth and release water on impact–possibly enough to have filled the ocean basins over geologic time. Studies of comets indicate that they may contain up to 0.5 percent water. If the early Earth contained the same percentage of water, it would have been more than sufficient to form the early oceans. Shortly after the formation of Earth, violent volcanism released huge amounts of water vapor, carbon dioxide, and other gases, which combined to form Earth’s early atmosphere. As Earth’s crust cooled, the water vapor gradually condensed into oceans.

Ocean water is a mixture of gases and solids dissolved in water

Which two substances are the most abundant in seawater? Constituents of Seawater Which two substances are the most abundant in seawater? Chloride, Cl Sodium, Na

What is salinity? A measure of dissolved solids (salts)in water Expressed as grams of salts/ kilogram of water or parts per thousand(ppt) Sometimes measured in PSU (practical salinity units) using electrical conductivity Avg. salinity of seawater is 35ppt or 3.5 %

Salt is naturally added to and removed from seawater. Salt added to sea by Volcanic eruptions Erosion of rocks which dissolve in water Salt is removed from sea by Sea spray Marine organisms Formation of evaporites (chemical rock)

Factors affecting salinity…..

RERUN Water Salinity Density Lab RECALL: Summarize what was done in the lab demo. EXPLAIN: Explain the purpose of the lab RESULTS: Describe the results of the lab UNCERTAINTIES: Describe what you are still unsure about NEW: Write at least two new things that you learned from this lab

Temperature OCEAN LAYERING Ocean water has the ability to absorb sunlight which heats the water Factors that affect the temperature: Latitude Depth Shore proximity

RERUN Water Temperature Lab RECALL: Summarize what was done in the lab demo. EXPLAIN: Explain the purpose of the lab RESULTS: Describe the results of the lab UNCERTAINTIES: Describe what you are still unsure about NEW: Write at least two new things that you learned from this lab

Density Salinity Temperature Two factors affect density: Halocline – layering of ocean water due to different salinity levels) Temperature Thermocline – layering of ocean water based on different temperatures

Answer the Essential Question in your learning log