Salinity of the Oceans
Introduction: Different bodies of water have different amounts of salt mixed in, or different
salinities. Salinity is expressed by the amount of salt found in 1,000 grams of water (ppt). The
average ocean salinity is 35 ppt. This number varies between about 32 and 37 ppt. Rainfall,
evaporation, river runoff, and ice formations cause the variations. For example, the Black Sea is so
diluted by river runoff, its average salinity is only 16 ppt. Salinity of the top layer of the ocean is
closely linked with precipitation and evaporation. Evaporation leaves behind dissolved salts
increasing salinity and precipitation "freshens" the top ocean layers. So, salinity is high in mid-
latitudes where evaporation is high and precipitation is low. Salinity is low near the equator
because precipitation is so high. Very high latitudes can also see decreases in salinity where sea
ice melts and "freshens" the water.
1) What is the relationship between salinity and evaporation?
2) Where is ocean salinity high? Why is it high in these locations?
3) Where is ocean salinity low? Why is it low in these locations?

Interpret the model. a three-part model with black right-arrows between the parts. left part: a large green apple-shaped component with a w-shaped indentation centered on top. a small blue apple-slice shape sits above the left indentation and an arrow points from the shape to the indentation. a small purple apple-slice shape and arrow sit above the right indentation and an arrow points from the shape to the indentation. middle part: a large green apple-shaped component with a square indentation centered on top. sitting in the left side of the indentation is a blue apple-slice shape with a flat bottom, fused to a purple apple-slice shape with a flat bottom on the right side of the indentation. right part: a large green apple-shaped component with a w-shaped indentation centered on top. an up-arrow is centered above the indentation pointing to a fused blue and purple apple-slice-shaped flat-bottom component sitting above the indentation. assigne "true" or "false" to the end of each statement. the model shows a shape change occurring in the enzyme after the substrate is bound in the active site. t/fthere are two products in this model. t? f there are three substrates in this model. t/f the model shows two different enzymes. t/f

Which of the following two events occur to create a sea breeze? select all that apply. warm air rises on the ocean and moves toward the land to cool warm air rises on land and moves toward the ocean to cool cool air moves from the ocean to be warmed by the land cool air moves from the land to be warmed by the ocean

Which of the following produces carbon dioxide? a. plants b. animals c. decomposers d. all of the above