840 likes | 919 Views
Waters of the Ocean. Water. It makes up 80% of a Marine Organism’s body. ex 98% of a jelly fish. Other properties of water. Adhesive – ability to attract to objects Cohesive – ability to attract to other water molecules.
E N D
Water It makes up 80% of a Marine Organism’s body. ex 98% of a jelly fish
Other properties of water Adhesive – ability to attract to objects Cohesive – ability to attract to other water molecules. Hydrogen bonding occurs between water molecules. When Hydrogen is attracted to highly electronegative atom. Electronegativity- ability of an atom to attract electrons towards itself.
Nature of Water All matter is made up of atoms. Matter-Anything that has mass and takes up space. Atoms – smallest unit of matter Elements – Substance composed of individual atoms of the same kind. 104 known elements Molecule is two or more atoms that are forced together. H20 is made up of 2 H atoms and 1 O atom.
Water is a Polar molecule Uneven distribution of charged due to electrons not shared equally. This causes a partial negative on the Oxygen. The electrons are pulled toward the Oxygen that creates this uneven distribution of charge. Creates an Universal solvent. “Like dissolves Like” Polar substances dissolve other polar substances
Physical States of Water Exist in three states liquid, solid and gaseous Triple Point of water- When conditions are right. Conditions meaning temperature, pressure and volume, water can exist in all three states at once.
Changes of State Requires energy. Temperature reflects the average speed of the molecules Melting- solid to liquid Energy required – Latent heat of melting. Molecules begin to vibrate and break bonds to move away as temperature increases. Energy is absorbed by the bonds not into the speed of the molecular motion.
As the atoms breaks free, molecules speed increases with temperature. Water has a High Heat Capacity- Specific heat. 1.0 g/degree C Latent heat of evaporation ( heat of Vaporization)
Heat of fusion – Liquid to a solid All Changes of state requires a steady temperature except the specific heat of a substance that is depend on a change in temperature.
Water as a Universal Solvent Dissolves Salts – Combinations of particles with opposite charges. Ions- Particles that have given electrons away ( +) or receive electrons (- ) Crystals break apart from the water molecule pulling on the ions. Then once the ion is off, other water molecules congregate around it and carry it into solution.
Sea Water • Salts come from two main sources. • Chemical weathering of Rocks • From the earth interior through the hydrothermal vents. • Six ions compose 98% of the solutes in sea water • Na and Cl ions makeup 85% of the solids.
Salinity Total amounts of salt dissolved in sea water. It is expressed over 1000 g of seawater that has been evaporated If you have 35 g of salt left, then the salinity is 35 o/oo parts per 1000. Organisms are affected by the kind of ions not the amount in the water. DITTMAR – A scientist that tested salt water for the consistency of ions in the water. Found the the amount did not vary.
Salinity Changes in salinity is controlled by : Precipitation Evaporation Freezing - ice is pure water/salt separates from it. All processes occur at the surface.
Salinity continued. Average Salinity – 35 0/oo Open Ocean varies from 33 – 37 0/oo Red Sea 40 o/00. Due to being partially enclosed. Baltic Sea 7 0/oo. Due to river runoff.
Salinity- Temperature - Density Saltier the water, the denser. Density depends on temperature and salinity of water. Open Ocean temperature 28 F to 86 F Salt water freezes below 0 C. Temperature varies considerable in the ocean. It is measured with a reversible thermometer. The mercury column breaks when inverted at the temperature reading from the water column. A series of these thermometers are use to develop a ocean profile.
Dissolved gases Oxygen, Carbon Dioxide, Nitrogen Gas Exchange between ocean and atmosphere occurs through a variety of processes.
Transparency Sunlight needed for plants to produce oxygen. Depends on materials on the water. Ocean water is most transparent to blue light from the visible spectrum of white light. Consist of: R O Y G B I V
Pressure Land organisms are less than 1 atmosphere of pressure. Pressure increases with depth with every 10 m another atmosphere is added. Gases are compressed, Gas filled structures tend to collapse.
Ocean Circulation Surface Circulation - surface currents are driven by wind. Coriolis effect influences surface current and wind - Earth rotates and is round which causes anything moving to be not in a straight line. In the Northern Hemisphere we tend to deflect to the right. In the Southern Hemisphere we tend to deflect to the left.
Wind patterns winds driven by heat energy of the sun. Sun is directly over the equator. This causes direct heating. Warm air rises. Cooler air is sucked in this area and this creates wind. Winds are bent due to Corioles Effect. Trade Winds - blow at 45° angles towards the equator. They are the steadiest winds on Earth/ Why? No land around.
Westerlies - middle latitudes - moves opposite of trade winds - variable. Polar Easterlies - high latitudes - most variable winds - these are the most variable. Variable winds move opposite of Trade Winds. Surface currents - all major surface current are driven by winds. . Winds push the upper layer of the surface layer and moves at 45˚ angle. 2nd layer moves slightly to the right and slower. Upper part of surface current is called the Ekman Layer and they tend to move at 90˚ from the wind direction. Layers of water move in different directions and rates called the Eckman Transport
Gyres - huge circular movements of currents that carries warm water in one direction - regulate climate.
Cold water is carried in another direction. Currents regulate the climate on the Earth. Carrying heat from the tropics to polar regions. Continental shelf - currents tend to shape the bottom, shape coastline and affects tides.
Stability and Overturn Ocean is layered or stratified Dense water is on the bottom to the least at the top. Surface water stay always on top of the column of water is stable Only the winds and waves mix the deep water with the surface. Greater the difference in density the more stable the water column.
Overturn Surface Water sinks displacing less dense water below Profile (temperature ) is straight down, Occurs in the temperate and Polar regions in the winter when the surface water cools. It bring oxygen rich surface water to the deep sea.
3 Layered ocean Processes Changing: Temperature Evaporating- cooling Solar heating Heat exchange with the atmosphere. Water masses finger printed by temperature and salinity. This aids in the following circulation
3 layered ocean continued • 1. Surface Layer • --330 ft- 660 ft deep • --Mixed by wind, waves and currents. • Called the mix layer • --- Thermo cline occurs with a sudden temperature changes due to surface heating.
Intermediate Layer 1500 m (5,000) deep Main Thermocline Zone of Transition between warm surface water and cold water below and rarely breaks down,
Deep Bottom Layers 1,500 m (5,000 feet) uniformly cold less than 4 C