OCNG 251: EXAM 2

· Ionic bonding some atoms loose electron from outer shell and other atoms gain electrons in outer shell · Covalent bonding: electrons in outer shell of atoms are shared

· Water is a polar covalent molecule · Is formed by 2 hydrogen joining together with oxygen in a shared covalent bond · Hydrogen bonding: Because of polar molecules they want to line up like magnets, extra bond is the hydrogen bond · Hydrogen bonding causes surface tension which causes the surface of water to act like a “skin” or “membrane”

· high latent heat capacity (weather modification)
 · freezing and boiling temperatures (liquid water at earths surface) · 
expansion upon freezing
-high surface tension (capillarity)
 · high dielectric constant (dissolving power)

· 1 calorie- is the amount of heat required to raise the temperature of 1 gram of pure water by 1 degree Celsius · latent heat of melting- the heat energy that must be added to 1 g of a substance at its melting point convert to a liquid 80 cal/g C degrees · latent heat of vaporization- the heat energy that must be added to 1 g of a substance at its boiling point to convert it to a vapor 540 cal/g C degrees

· heat capacity is the amount of heat energy required to raise the temperature of a substance by 1 degree centigrade · high heat capacity can absorb large quantities of heat with only a small change in temp · pure water has high specific heat = 1 c per g bc it takes more energy to increase the kinetic energy of hydrogen- bonded water molecules than it does for substances in which the dominant intermolecular interaction is much weaker · heat capacity- measures the amount of heat required to raise the temperature of 1 gram of that substance by 1 degree C · the specific heat capacity of rocks is much lower than water

· Unbonded molecules pack more closely together density increases · Greater proportion of H-bonded ice-like clusters density decreases

· dissolved solids reduce the freezing point of water · water is the solvent for the solution that is ocean water · salts are the solutes in the ocean water · salinity is the amount of dissolved solids in seawater · Parts per thousand (g/kg) or (‰)- grams of a substance per kilogram (1000 g) of ocean water · Divide by 10 to get back convert · 1 kg has 35 ppt salinity 35 g of salt

chloride, sodium, sulfate, magnesium, calcium, potassium all dissolved in water · what determines salinity? – tastes, optical refractometer, titration for Cl ion, electrical conductivity · highest salinity- atlantic ocean closer to equator · salinometer- measures electrical conductivity, increases as more substances are dissolved in water · brackish- runoff, low salinity Baltic sea · hypersaline- high evaporation rates, higher salinity Red sea

· sea ice forming and evaporation increase salinity · Pure water has a maximum density of 1.000 g/cm3 at 4°C · Ice floats because its density is 0.9170 g/cm3 · At T=20 °C, S=35 ppt, seawater density = 1.0247 · Increased salinity, increased density · Increased temperature decreased density

· Acidity- is a measure of reactivity of a solution associated with its hydrogen ion concentration · Alkalinity- is a measure of the buffering capacity of a solution (ability to NEUTRALIZE the hydrogen bond) · the pH of the solution tells you its degree of acidity of alkalinity · water is a neutral pH · the ocean has a large buffering capability · what is buffering do for the ocean? it protects the ocean from getting too acidic or too basic · What happens to the CO2 in buffering in the ocean? it breaks down and becomes less acidic · as the pH level decreases, the dissolved carbon dioxide increases

·solar flairs- huge amounts of energy (earth is tiny compared to it)

· the tilt of the earths axis relative to the ecliptic caused seasons – always points towards the north star · coldest day is the winter equinox- directly above tropic of Capricorn · longest day is the vertical equinox – directly above equator · heat is gained in equatorial and sub tropical regions · heat is lost in artic and Antarctic regions

· sun strikes low latitiudes at a high angle so the raditons is concentrated in a relatively small area · earths atmosphere absorbs some radiation, less strikes the high latitude · energy of sun covers more surface area
-greater thickness of atmosphere (beam of light has to pass though more air)
-lower strike angle
-greater albedo (radiation reflected back to earth) · heat budget is balanced because the gozinter (higher latitude/heat) = gozounter (lower latitude/heat) · tropics DON’T get continuously warmer and poles colder · warm air rises/ cold falls

· the coriolis effect- go in a tangent direction of the way the merry go round is turning if you let go · northern hemisphere follow curved paths to the right/ south, left · effect greates at the poles, and 0 at the equator · depends on your latitude, speed of object over the earth, square of the travel time to get to the target · closer to the center of the earth, the speed decreases

· Northeast trades blow from the NE to SE · In the ocean the winds are opposite · In the ocean the north current flows towards the north · Polar cell- are at the pole, polar easteries · Ferrell cell- are at ground level and come from W. Hadley cell (NE trades), prevailing westerlies · Simple convection cell breaks into 3 zonal (E-W) cells in each hemisphere) Between the polar and Farrell is the polar front that is made from convergence

· Clockwise (anticyclonic) winds around high pressure cells · Counterclockwise (cyclonic) winds around low pressure cells · Air or water flow around a low-pressure center in the Northern Hemisphere

· Anticyclonic is clockwise winds around high pressure cells · Cyclonc is counterclockwise winds around low pressure cells · Cycogenesis a wave distribution of the polar front (what produces mid latitude weather) · Tropical cyclones (hurricanes)- huge rotating masses with winds speeds of less than 120 km · Latent released by condensation (rain) is the energy source · Storm surge- pushes the low pressure and storm on the shore 90% deaths · Warm core ring- like a blow firing the storm · Largest disaster- Galveston hurricane · Hurricane category scale- saffir simpson scale

· Greenhouse gasses absorb energy radiated by the earth back into the atmosphere, change of wavelength is the key · Keeps the earth at 15 degree C · Without the effected it would be -18 · The amount of greenhouse gasses that come have to equal the amount going out

· Wavelength of max radition is inversely proportional to the temperature · Sun is 600 and earth 18 degrees C · Energy that is reflected from the surface back to space is albedo

· Carbon dioxide has an increased -(400 x10^3) concentration (ppbv) 
-.5 rate of increase (% per year)
-60 relative contribution (%) · Methane has an increased -1.7x10^+3 concentration (ppbv)
-1 rate of increase (% per year)
-15 relative contribution (%)

· Human activites are causing carbon dioxide and other greenhouse gases to accelerate · Recent record shows increase in greenhouse gases since industrial revolution · Over 140 years 1 degree of C increase

· Potential natural causes of climate change: -changes in solar energy flux
-variations on earth's orbit
-volcanic eruptions
-tectonic movements of crustal plates · Consequences of greenhouse: -shifts in weather patterns (warm water oceans)
-global rise in sea level (melting glaciers)
-agriculture and food supply · 
Potential natural causes of climate change 
changes in solar energy flux 
 probably not significant on climatic time scales

° variations in earth’s orbit
 100, 41 and 26 thousand years (Milankovitch cycles)

° volcanic eruptions
 dust clouds in the atmosphere are relatively short-lived

° tectonic movements of crustal plates
 major changes in ocean currents: e.g. Antarctic Circumpolar Current
 · Sea level will cause the N gulf of mexico to rise by 2-3 mm per year · China and India accounted for 37% of population

· Caused a permanent ice cover on the sea surface from low pressures · Ice forms

· Horizontal currents that are caused by winds blowing over the surface · Thermohlaine currents: vertical currents caused by sinking of high density waters and rising of low density waters

· Atlantic ocean surface circulation: north gyre o Goes clockwise, driven by westies · Atlantic ocean surface circulation: south gyre o Counterclockwise, driven by trade winds · Suptropical gyres: -equatorial current
-western boundary currents (west side of ocean basin)
-northern or southern boundary currents
-eastern boundary currents · Western boundary currents: -west side of the ocean basin
-the coriolis effect deflects these currents away from equator · Each gyre has it owns western boundary current

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· V walfrid Ekman developed a circulation model called the Ekman layer · The layer flows at 45 degrees to the winds and is confide to the top 100 m, net flow is 90 degrees to the wind (Ekman transport) · The transport is 90 degrees to the right in the NH and 90 to the left in the SH · Gestrophic gyres: Gestrophic gyres · -"earth turned"
-huge cereal bowl that has a huge pressure system in the middle
-steep slope on one side · gestrophic gyre- where is the strongest and weakest flow o strong flow is the Western boundary current on the steep side
-the weak flow is on the other side

· Costal Upwelling is caused by ekman transport pulling near-surface waters away from the coast · Deeper waters "upwell" (move upward" to replace the surface waters moved offshore · the deep waters usually are cold and rich in nutrients and dissolved oxygen · Near the surface with good light is called euphoric zone · the euphoric zone contains nutrient rich waters that support vigorous life · Where does costal upwelling occur? Northern hemisphere · Downwelling pushing water against the coast and brining it to the bottom

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· large tropical gyres in each hemisphere, driven by Trades and Westerlies · warm water moves poleward in western boundary current · atlantic ocean surface currents: cooler water moves towards equators on the east sides · atlantic ocean surface currents: south equatorial currents splits against S America and partly joins the NH gyre · the gulf stream is stonger than brazil current

· Antarctic circumpolar current is the only current that can completely circle the earth · Loop current eddy usually breaks off and creates stong clockwise currents · Gulf stream connects with florida current · Warm currents can come in between cold water menders and create loop eddys · Gyres is where you can find high salinity water · when the surface water in the equatorial currents is pulled way from the equator by the Coriolis effect, its called equatorial upwelling upwelled water is full of nutrients

· El Nino influx of WARM water occurring every 5-10 years · the onset of El Nino is associated with the weakening of the Trade Winds in the Pacific Ocean · temperature difference is called anomaly · La Nina influx of COLD water · La nina can cause drought conditions in the South and Southwestern parts of the US · Multivariate ENSO index gives you an indication of if you are in a El nino or a La nina

· thermohaline circulation is the vertical movement of ocean water driven by density differences that result from combined effects of temp and saline

· stable stratification (science experiment) resist vertical mixing · unstable stratification (science experiment) easily mixed
-convection/overturning occurs · 3 layer cake (with frosting) contains: warm surface layer (frosting)
-Antarctic Intermediate Water (AAIW)
-North Atlantic Deep Water (NADW)
-Antarctic Bottom Water (AABW)

· Indian Ocean creates circulation called monsoons · Monsoon NH winter-air is cold, atmospheric high pressure over the content and moves Southwest · Monsson NH summer-low pressure (hot land)- go from southwest and goes to the right · pacific is 3 times wider then the atlantic so the gyres are more elongated · Equatorial Countercurrent more strongly developed 
-northward asymmetry · the N. Pacific is confined by Asian N.A. landmass · western boundary currents are the Kuroshio and East Australian Current · Trade wind swings are strongest near the equator · where are the trade wind swings the weakest? doldrums · equatorial currents occur both north and south of the equator and drive the water to the west · water piles up against the contents and flows back to the east along the equator where the CORIOLIS effect is ABSENT, causing equatorial countercurrents

· Antarctic Circumpolar Current or West Wind Draft is the only current that flows completely around the globe from West to East · Antarctic Divergence separates the East and West Wind Drift currents and is an upwelling region · does the pacify extend as long as the atlantic? no because of the arcs · climate change is particularly sensitive to thermohaline circulation in North Atlantic Ocean · Fridjof Nansen- Fram noticed the ice was drifting to the right of where the wind was blowing
-told Ekman and creation of Ekman layers