OCNG 251Exam # 2 Study Guide Summary of Emails1. Scientists Discover Thousands Of Uncharted Mountains Hidden Beneath The Sea- new topographic map of the earth discovers volcanos or seamounts - altimetry measures sea surface height from space by timing how long it takes a radar signal to reflect off the ocean and return- suggests the volcanoes did not erupt above a mantle plume, a blob of hot rock that rises from the deep mantle (the layer under the crust)2. 35,000 walruses are swarming Alaska's shore — because their sea ice is vanishing- scientists observed one of the biggest land haul-outs in recent memory in northern Alaska with an estimated 35,000 walruses crowding the shore of a remote barrier island near Pt. Lay3. Ditch U.N. temperature target for global warming, study says- world's environment ministers agreed in 2010 to cap a rise in average surface temperatures at 2 degrees Celsius- OSLO (Reuters) believe the goal should be ditched- effectively unachievable 4. Unexpected meteorite crash in Nicaragua highlights necessity of space program to protect from imminent danger- a meteorite crashed in Nicaragua's capital Managua on September 7- the government reported, raising new concerns that human civilization remains unprepared for the potential of catastrophic space impacts.5. Strange-Looking Sea Creature Discovered on Ocean Floor- scientist found a strange sea creature that resembles some kind of siphonophore that only live in the deep oceanCh. 5: Water and seawater I. Atoms, isotopes and moleculesA. Atoms: basic building blocks of matter- can be represented in spheres in various sizes- Atomic number is the number of protons in the nucleus- Atomic mass is the number of protons and neutrons in the nucleusB. Isotopes: Atoms with the same atomic number but different number of neutrons; therefore a different atomic massC. Molecules: a group of two or more atoms held together by mutually shared electrons- smallest form of a substance- Hydrogen has 1 electron- Oxygen has 8 electronsII. Covalent, ionic and Gary US bondsA. Covalent: due to the sharing of hydrogen and oxygen atomo a lot of energy to break themB. Ionic: produced by an electrostatic attraction between oppositely charged ions C. Hydrogen: weak attraction between a partially positive Hydrogen and a partially negative Oxygen or Nitrogeno weaker than covalent bonds III. Structure of the polar water molecule: the hydrogen bondA. Polarityo Water is polar because the single electron from each of the two hydrogenatoms being shared with the larger oxygen atom (covalent bonds) spend more time near the oxygen causing it to be slightly negative and the hydrogen atom to be slightly positiveIV. The anomalous properties of water- High latent heat capacity-weather modification- High freezing and boiling temperatures-liquid water at Earth’s surface- Expansion upon freezing-weathering of rocks- High surface tension-capillarity- High dielectric constant-dissolving powerV. Changes of state in water: latent heats of melting and vaporizationA. Latent heat of melting: The heat energy that must be added to 1 g of a substance at its melting point to convert it to a liquid.B. Latent heat of vaporization: The heat energy that must be added to 1 g of a substance at its melting point to convert it to a liquid.VI. Heat capacity of land vs. water; impacts on climateA. Heat Capacity: The heat capacity of a substance measures the amount of heat required to raise the temperature of 1 gram of that substance by 1°C- The heat capacity of a substance measures the amount of heat required to raise the temperature of 1 gram of that substance by 1°C Because of water’s high heat capacity oceans have moderate climates while land continental areas experiencemuch larger changesVII. Solutions and dissolving power of waterA. Solution: A state in which a solute is homogeneously dissolved in a liquid solvent- Water is the solvent for the solution that is ocean water- Salts are the solutes in ocean waterVIII. Salts in seawater; definition and measurement of salinityA. Salinity: Amount of dissolved solids in seawaterB. Ocean Water- 96.53% water- 3.47 % or 34.7 ‰ dissolved solids- Chlorine, sodium, sulfur, magnesium, calcium and potassium make up 99% of dissolved solids in ocean waterC. Units- Parts per thousand (g/kg) or (‰)- grams of a substance per kilogram (1000 g) of ocean water- Parts per million (mg/kg) - milligrams of a substance per kilogram (1000 g)of ocean waterD. Measurement- taste- optical refractometer- titration for Cl ion- electrical conductivityIX. Density of pure water and seawater: dependence on T,SA. Pure Water- maximum density of 1.000 g/cm3 at 4°C- density increases as the temperature decreasesB. Seawater- saltier the water, the denser it becomes and lowers the freezing point to below 0 degrees - At T=20 °C, S=35 ppt, seawater density = 1.0247- Latitude and depth determine the temperature and affect the salinityX. Typical T,S and density structures in the oceanA. Pynocline- Zone in which density increases with increasing depth- From 0-1,000 meters- Increasing density farther down as temperature gets colderB. Halocline- Zone of rapid salinity increase or decrease with depth- Often coincides with thermoclineC. Thermocline - Temperature changes rapidly with depth.- Both thermocline and halocline contribute to form pycnocline since temperature and salinity affect densityXI. Acidity, buffering and pHA. Acidity: a compound that releases hydrogen atoms when dissolved in water- rainwater is acidB. Buffering: protects the ocean from getting too acidic or too basic - ocean has a large buffering capacityC. pH: measure of the hydrogen ion concentration- rain water about 6- seawater about 8- pure water 7Ch. 6 Air-Sea InteractionI. Energy from the Sun- Solar energy heats the surface of the earth - creates atmospherics winds therefore they drive most of the surface currents and waves in the ocean- radiant energy is responsible for motion in the atmosphere and the oceanII. Seasons and the Earth’s orbitA. Seasons- The spin axis is tilted 23.5° to the plane of the Earth's orbit, causing solar radiation to vary in angle as the Earth revolves around the SunB. Earth’s orbit- Plane of Elliptic Surface: connecting all points on Earth's orbitIII. The global heat budget and redistribution of heatA. Global heat budget- describes all