Motion in the ocean Chapter 3

Water is the coolest molecule Water exists in 3 states: solid, liquid and gas It is held together by hydrogen bonds It has unique properties such as surface tension and capillary action

Ice floats on water. This is critical to our planets survival Ice insulates the water below Provides an ecological niche

SeaWater Contains more than just salt NaCl Weathering and erosion from land wash large amounts of minerals into the sea Hydrothermal vents bring minerals to the surface For every 100 g of seawater there are 3.5 g of minerals 85% of these minerals are NaCl, but K+, Mg+2, SO4-2, Ca+2, HCO3-1, Sr+2,F-1 and H3BO4-1 ions are all included

Dissolved gases Nitrogen and Carbon dioxide and oxygen are dissolved gases critical to life in the ocean While most solids dissolve better in warm water, gases dissolve better in cold water This is critical for life in the ocean, and to life on the land The phytoplankton need CO2 for photosynthesis to produce O2 for us.

Transparency Sea water is relatively transparent Sunlight can penetrate the water Suspended solids and plants cut light transmision Blue light penetrates the deepest because it is the most energetic, red the least

Pressure Each 33 ft adds an additional atmosphere of pressure Gases are compressed Gas filled organs such as bladders and lungs are compressed

Surface circulation Coriolis effect: because of earths rotation, water in the northern hemisphere will move to the right and water in the southern hemisphere will move to the left. http://www.youtube.com/watch?v=Wda7azMvabE&feature=related Wind patterns are driven by the heat of the sun. warming equatorial air moves up, sucking cooler air from the north in to replace it. This causes movement of air called the trade winds. http://www.youtube.com/watch?v=Hu_Ga0JYFNg&feature=related http://www.youtube.com/watch?v=w_8mw-1HYFg&feature=related

Surface currents Wind fields of the atmosphere push the sea creating currents. The wind direction does not equal the surface direction because the coriolis effect bends the direction The water moves in huge circular patterns called gyres http://www.youtube.com/watch?v=YCorkyBe66o

Current density Cold water is more dense than warm water because the molecules are closer together Salinity: higher salt content makes water more dense…this occurs at the polar ice caps as the water freezes out the salt Also evaporation leads to more salty water http://www.youtube.com/watch?v=FuOX23yXhZ8&feature=relmfu

Ocean temperatures

Waves Wind causes waves The top is called a crest , the bottom is the trough Wavelength is the distance between 2 crests The number of wave passing a point in a given time is the period of the wave The fetch is the span of water over which the wind is blowing

Vertical Motion The water column is divided into three zones: surface layer, intermediate layer and the deep layer All layers are controlled by salinity and temperature

Changes in the layers Seasonal sunlight penetration, warms the water and it becomes less dense Dense saline water sinks Very cold water sinks Wind can cause changes

Buffer solution, a solution which reduces the change of pH upon addition of small amounts of acid or base, or upon dilution http://www.youtube.com/watch?v=KUadxcKtH-g&playnext=1&list=PLEEF8C04CD2B9ACD0 <iframe title="YouTube video player" width="480" height="390" src="http://www.youtube.com/embed/KUadxcKtH-g" frameborder="0" allowfullscreen></iframe> http://www.youtube.com/watch?v=ANacc8saHvw