海洋學复习资料(董志南整理).docVIP

个人观点，仅供参考，如有异议，欢迎讨论，敬请不吝赐教 ——董志南 Water and Ocean Structure 1. Why is water a polar molecule? What properties of water derive from its polar nature? Because Water structure is: one oxygen atom is in the above direction, two hydrogen atoms below are connected to the oxygen atoms. the bond angle of them is about 105 degrees,. The positively charged center of water is in the following, while the negative one is in the above. The two centers do not coincide, Polarity can not cancel each other out. Cohesion – the ability of water molecules to stick to each other, creating surface tension Adhesion – the tendency of water molecules to stick to other materials, a good solvent Dissolving Property of Water These propertiese derive from water polar nature. 2.How is heat different from temperature? Temperature is a measurement of the heat content of a body. Heat content is energy expressed in Joules or Calories. heat is thermal energy transferred from one object to another because of a temperature difference。The two quantities are related by a factor called the specific heat capacity cp: H = cp*m*T, where m = mass and T = temp in oK 3.Why does ice float? Why is this fact important to thermal conditions on Earth? Because the density of ice is less than that of water, when water is in liquid form, the composition of molecule is closer than that of solid form. The space between the ice molecules is more than water molecules. so the ice is lighter than the water with the same quanlity. 因为水在4℃时密度最大，在海中也是处于最低的位置，因此浮冰下的水，其温度皆高于最表层的冰。无论气候如何变化，海面下温度都保持一定，因此生物得以生长；另外水的潜热（Latent Heat）高,当冰灾水面上时，需要更多的热量来使冰转化成水，这是一个非常重要的原因。它使得地球气候得以调节，不至于变化过于剧烈。（中文意思大概如此，自己用英语转化一下就行了） 4.How is heat transported from tropical regions to polar regions? Water helps moderate global temperatures by redistributing equatorial heat poleward. Warm current from tropical regions goes to polar region; at the same time, cold current form polar region goes to tro