When the water sinks, it drives a current that plays a significant role in global ocean circulation. This causes the density of the water to increase, and the water eventually sinks as it enters the North Atlantic. In this area, surface water moving north from low latitudes becomes saltier (due to evaporation) and colder as it moves northward. In the North Atlantic, a phenomenon based on this concept drives a process known as thermohaline circulation or the “great ocean conveyor belt” (Windows to the Universe, 2007). Thus, saltwater is denser than fresh water and fresh water will float on the surface of seawater. When salt dissolves in water, the salt adds mass to the water but does not increase the volume of the water very much.
![density of fresh water density of fresh water](https://sciencekiddo.com/wp-content/uploads/2016/05/Salt-Water-Experiment-Ocean-Science-for-Kids-1.jpg)
Allow the ice to melt and watch where the fresh water (blue color) accumulates.Use the colored ice in place of regular ice, and build your “landlocked ice” box as previously outlined, using the cold, salty water to pour into the container.This could cause the colored fresh water to sink instead of float.
![density of fresh water density of fresh water](https://i.ytimg.com/vi/HVrykjEmHxQ/maxresdefault.jpg)
If the water from the melting ice is significantly colder than the saltwater in the pan, the difference in density (caused by variation in temperature) may negate the effect of the difference in salinity. *It is important to use cold water for this activity because, as discussed earlier, liquids become denser as they cool. This makes your water approximately the same salinity as the ocean. Add salt to the water that will be poured into the boxes in a ratio of 3 tablespoons of salt to 1 liter of refrigerated water*.This will make colored ice (the darker, the better). When freezing the ice cubes, put lots of food coloring into the water before filling the trays.Density differences between water layers determine whether a layer will float or sink in relation to other water layers.Conduct the same experiment as in Global Climate Change and Sea Level Rise with the following modifications: To build an understanding of the densities of seawater and fresh water and of how water density differences affect ocean circulation, it is important to understand how temperature and salinity differences form water layers of different densities. The salt in seawater comes from eroding land, volcanic emissions, reactions at the seafloor, and atmospheric deposition. Seawater has unique properties: it is saline, its freezing point is slightly lower than fresh water, its density is slightly higher, its electrical conductivity is much higher, and it is slightly basic. Ocean Literacy Fundamental Concept: Most of Earth’s water (97 percent) is in the ocean.
![density of fresh water density of fresh water](https://shiphistory.org/wp-content/uploads/2020/04/IMG_7421-1-scaled.jpg)
The shape of the ocean basins and adjacent landmasses influence the path of circulation. Ocean Literacy Fundamental Concept: Throughout the ocean there is one interconnected circulation system powered by wind, tides, the force of the earth’s rotation (Coriolis effect), the sun, and water density differences. Principle 1: The earth has one big ocean with many features The relative floating and sinking of water masses affects vertical ocean circulation. For example, fresh river water floats on top of salty ocean water (Fig. The relative density of each water mass determines whether it will float or sink in relation to another water mass. If water masses do not have the same densities, they will form layers of water. Even within one geographical area of the ocean, there are water masses with different properties. Water in the ocean is not uniform in its composition the properties of ocean water vary in different parts of the ocean.