Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
1. - Density ice at 0 C less than density water at 0 C Strong hydrogen bonds High heat capacity Exists in all three forms Many molecules remain bounded together in liquid state 2. Volcanic eruptions, weathering of rocks on land and chemical reactions between seawaters and hot, newly formed, crustal rocks (most important) 3. Temperature change, phase constant : Heat required = Q = m*cp*∆T, where cp = heat capacity Temperature constant, phase changes: Heat required = Q = m*L, where L = latent heat Five steps: Ice -10 C Æ ice 0 C : Q = 2000*0.5*10 = 10.000cal Ice 0 C Æ water 0 C: Q = 2000*80 = 160.000cal Water 0 C Æ water 100 C: Q = 2000*1*100 = 200.000cal Water 100 C Æ vapour 100 C: Q = 2000*539 = 1.078.000cal Vapour 100 C Æ vapour 125 C: Q =2000*0.45*25 = 22.500cal Q_total = 10.000+160.000+200.000+1.078.000+22.500 = 1.470.500cal = 1.47Mcal 4. Two reasons : water has higher heat capacity AND heat is mixed in ocean in the surface layer, whereas on land it stays near the surface 5. Areas with excess precipitation have low salinity; areas with excess evaporations have high salinity 6. 1: More warm water remains at west coast of South America (flatter ocean) . 2: No more upwelling of cold water off coast of South America 7. Ekman spiral: 3 crucial points: 1) spiral is wind-driven, 2) there is an angle between surface wind and surface current, but also deflection between layers in the ocean, 3) there is an energy transfer from upper layer to lower layer, but due to viscous dissipation energy is lost during this transfer process, resulting in lower speeds in deeper water. Real ocean: wind not steady, inhomogeneous, other currents present in ocean, boundaries, real ocean is more turbulent than laminar, etc. 8. Subtropical gyres are always anticyclonic (direction of rotation opposite to direction of rotation of Earth), i.e. clockwise on NH, and counterclockwise on SH. On NH, water is transported to the right of the current, on SH to the left. This results in net inward water motion in subtropical gyres on both hemispheres, giving rise to hills in their centers. For subpolar gyres, there are counterclockwise on NH and clockwise on SH, causing water to be deflected outward and the formation of valleys in the centre 9. Use formula: Time = distance/speed Gulf Stream: T1 = 1.000.000/1 = 1.000.000s NA current: T2 = 4.000.000/0.05 = 80.000.000s Î 1.000.000 + 80.000.000s = 81.000.000s = 22.500hours = 2.57years 10. Coastal upwelling: along western boundary (on NH), net water movement offshore, gives upwelling Equatorial boundary: Coriolis changes direction at equator. Westward wind causes water to be transported northward on NH and southward on SH. This results in divergence at the equator, water up welled from below.