Oceanography Exam Questions Fully Solved Latest

Oceanography Exam Questions Fully Solved Latest What is the difference between conclusions drawn using the scientific method vs. those reached on non-scientific grounds? - Answers Scientific method observes a phenomenon and asks a question, generates a hypothesis and predictions, experiments to test the hypothesis, and then draws a conclusion. What are the consequences of the high heat capacity of water for climate? - Answers Water absorbs a lot of heat with small increases in temp; releases a lot of heat with small decreases in temp which is a big deal for climate stability What is a conservative vs non-conservative property of seawater? - Answers Conservative: Properties that can only be altered at the sea surface (temp, salinity, inert gases, [Na+], [Cl-], properties not altered by biological or geochemical reactions. Non-Conservative: Properties that can be altered anywhere in the water column, opposite of conservative What is latent heat? - Answers a) Is energy released or absorbed by a body or thermodynamic system b) When water undergoes a change of state, large amount of heat is absorbed or released c) Amount of heat absorbed or released is due waters high latent heats d) Latent means hidden Why are water molecules attracted to each other, and what impact does this have on the physical and chemical properties of seawater? - Answers Water Molecules have polarity a) They orient themselves relative to one another b) Positively charged hydrogen area of one water molecule interacts with a negatively charged oxygen end of adjacent water molecule c) Hydrogen bond between water molecules are weaker than the covalent bonds that hold individual water molecules together d) This hydrogen bond are strong enough to cause water molecules to stick to one another and exhibit cohesion e) This gives water surface tension f) Water molecules also stick to other polar chemical compounds g) Water moelcules can reduce the attraction between ions of opposite charges by 80 times What are some of the major physical properties of water? - Answers a) Only substance that is found on earth as solid liquid and gas b) Water has a high specific heat capacity c) Water has high latent heat d) Water has very unique density. Ice floats on water e) Cohesive behavior f) Great solvent power for ionic substances g) Cannt dissolve molecules that are non-polar Which state of matter is USUALLY the densest? In which material is this the exception? - Answers Solid, liquid water is exception, denser than ice How does salinity vary generally with latitude? Depth? - Answers Salinity lower at high and low latitudes, high around 0 latitude. Salinity increases with depth Why are the oceans salty? - Answers Chemicals leached from rocks in the other layer, volatile chemicals from the interior and volcanoes which would have been salty early on. More salts accumulated in oceans as rocks broke down by erosion What are two possible sources of water on Earth? - Answers Rain and water-rich minerals in meteorites How does the Coriolis Effect affect the circulation of the atmosphere? How does it affect the circulation of the ocean? How would the circulation of the oceans and atmosphere differ if the Earth didn't rotate? How about if it rotated in the opposite direction? - Answers 3 cells per hemisphere: Polar - Active (updraft on hot side, downdraft on cold side), Ferrel - Passive (downdraft on hot side), Hadley - Active (updraft on hot side, downdraft on cold side). Latitudinal winds: 0-30 Trade Winds, 30-60 Westerlies, 60-90 Polar Easterlies. Accelerates ocean currents, frictional drag so speed of water is reduced. If Earth didn't rotate currents wouldn't move 45 degrees relative to forcing wind, "ekman" response. The atmosphere would circulate between the poles and the equator in a simple back-and-forth pattern. Describe the types of ocean currents. - Answers Equatorial Currents: Found on either side of the equator, flow to the west. Boundary Currents: Western: Carry warm water from tropics poleward on west ocean basins, Eastern: Eastern side of ocean basins, flow equatorward transporting cold water from high to low latitudes. All these currents in the North/South Pacific/Atlantic gyres South Surface currents: Make up 10% of water ii) Upper 400m of ocean Deep Water currents: 90% of the ocean Move around the ocean basins by density forces Density is relational to temperature and salinity Wind Driven Currents Ekman transport: 90 degrees to right in North Hem 90 degrees to the left in south hem What is upwelling and why does it occur? - Answers Deep, cold water rises toward the surface due to winds blowing across the ocean surface pushing water away, and water then rises up from beneath the surface to replace the water that was pushed away. Occurs in the open ocean and along coastlines What is the difference between western and eastern boundary currents? - Answers Eastern Boundary Currents: Shallow, broad and slow-flowing. Found on eastern side of oceanic basins, flow equatorward transporting cold water from higher to lower latitudes. Western Boundary Current: Warm, deep, narrow, fast flowing currents on west side of ocean basins. Carry warm water from tropics poleward. What is a gyre? - Answers Large system or rotating ocean currents involving large wind movements caused by the Coriolis Effect. Main gyres: Indian Ocean Gyre, North and South Atlantic Gyres, and North and Pacific Gyres How does surface salinity vary with latitude? Why does it vary the way it does? - Answers High and low latitudes have lower salinity, and mid latitudes have higher salinity because it's hotter and water evaporates. At high and low latitudes melting icebergs and sea ice also decrease salinity Why does it rain a lot in the tropics? Why are the deserts in the subtropics? - Answers The equator is an area of low atmospheric pressure because it receives the most sunlight out of any place on Earth. This means that the level of evaporation is higher, and therefore there is more moisture in the atmosphere. This low-pressure system creates storms with large amounts of precipitation. Northern and Southern Hadley cells, a system of air and water vapor circulation near the equator, converge at the intertropical convergence zone (ITCZ), moving from 23 degrees N to 23 degrees S with season changes. The subtropical deserts center on the Tropic of Cancer and the Tropic of Capricorn. The aridity of these areas is due primarily to the general circulation of air around the Earth. Subtropical areas have consistently high atmospheric pressure because of descending air currents and are swept by hot, dry winds. Such conditions keep moisture-bearing winds from entering the region and prevent the formation of clouds (no