生态学课件C资料.pptVIP

Key Notes Solar energy drives climatic processes. Energy from the sun strikes the Earth where high-energy wavelengths of light are absorbed and re-emitted in the form of radiant heat. Warmed air rises, and expands as it does so. This expansion takes energy from the air, resulting in temperature reduction, a process known as adiabatic cooling. C1 SOLAR RADIATION AND CLIMTE Solar radiation 地球的风型 地球上主要的风系是由环绕赤道的热空气的上升运动而引起的，从南北而来的较冷空气替代了热空气，形成了信风。科里奥利（coriolus）效应（由地球的自转引起）使移动的空气在北半球向右偏转，在南半球向左偏转。南北两半球的信风恰好在赤道北部于热带辐合区（ITCZ）相遇。在南北纬40°地区的高层大气中，发生从西而来的“急流”风。地球两极的冰群增加了地球表面的反射系数和（或反照率），降低了空气的升温，产生了一些密集的冷空气带。 The major wind systems of the Earth result from the upward movement of warm air around the equator, which is replaced by cooler air coming form the mouth and south, forming the trade winds. The Coriolus effect (caused by the Earth’s rotation) deflects moving air to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. The trade winds meet just to the north of the equator in the intertropical convergence zone (ITCZ). At 40。North and southwesterly, upper atmosphere ‘jet stream’ winds occur. Ice packs at the poles increase the surface reflectance (or ‘albedo’) which reduces the heating of the air, resulting in zones of dense cold air. Global wind patterns 洋 流 风搅动着地球上的海洋，信风将海水掀起海浪冲向大陆，造成海平面的不平衡。例如，北美洲的海平面在大西洋一侧比太平洋一侧高一两米，这种差异形成了洋流。因此，如在加勒比海堆聚的温暖海水，沿着美洲海岸向北移动，即墨西哥湾流，然后转向欧洲北部，对欧洲具有显著的增温作用。 降 雨 潮湿的空气遇冷形成降雨。温暖的空气比冷空气携带更多的水，所以冷即使热空气凝结成小水滴，并以雨的形式降落。例如，如果空气在海上流过，然后沿山上升，这空气将以绝热温度递减率冷却，即每上升1000m温度下降6~10℃，这还取决于空气中的含水量，并将导致降雨。空气翻越过山后，将下降并被压缩变暖，导致在山的背风面形成雨影。 世界气候类型和洋流图 我国中东部将有降雨 台风杜鹃 The world’s oceans are stirred by winds. Trade winds pile up water against continents,causing an imbalance in sea levels. For example, in North America sea levels are 1or 2 m higher on the Atlantic side than the Pacific side. This difference drives oceanic currents, thus, for instance, warm water piled up in the Caribbean moves northwards along the American coast as the Gul