SLO 4

The Ocean and the Environment

Physical Properties

Temperature:

The ocean's temperature is approximately 2 to 30 degrees Celsius, equal to 35.6 to 86 degrees Fahrenheit. In low-altitude regions waters tend to be where it is warmest. When you are in areas like the poles it will be significantly colder. The patterns of surface currents are what cause this. Since the surface water is warmer, deeper water will be less dense. temperatures will remain consistent for 100-200 meters in the mixed layer. The mixed layer comes from surface winds, waves, and currents that mix in a temperature over an increase of depth called the thermocline. the deep ocean temperature change is minimal because it is far from heat sources, making it one of the most thermally stable regions on earth. temperature varies at different latitudes. Waters are warmer near the equator and colder at the poles. (Text Webb)

Pressure:

The physical properties of the ocean consist of pressure, temperature, density, sound, and light. The greater the depth, the more water above, and the greater the weight of the water. Surface atmosphere pressure comes from the weight of the atmosphere above us. the pressure increases by 1 atm. for every 10-meter increase in depth. so at 1000 meters, the pressure would ride to 101 atm. the average depth of the ocean is approx. 3800 meters. The pressure at that depth would be 381 times greater than the atmospheric surface pressure. Boyles Law states that the volume of gas is very much related to pressure. High pressure will compress airspaces, such as the lungs of a person, sea animals, and even submarines. Secondly, Henry's Law states that fluids constrain more gas at higher pressures. It applies to human divers directly. When you increase pressure, the amount of gas that can dissolve in a fluid increases, like blood. When pressure is reduced, the fluid holds less liquefied gas, and the excess gas will leave the solution as bubbles (text Webb)

Density:

The mass per unit volume is density. the density of fresh water is 1 g/cm3 at 4 degrees Celcius. salts and other dissolved substances increase surface seawater between 1.02 and 1.03 g/cm3. pressure has the most negligible effect on density. as with temperature, there are also differences in density. warm normally comes with low density whereas the cold will be dense.