|
|
|||||||||||||||||||||||||||||||
  |
|||||||||||||||||||||||||||||||
MORE EFFECTS ON TEMPERATURESWe were just talking about temperature differences over land and oceans. To be specific, it can get much hotter and much cooler over the land. The bigger change in temperature is because of how much heat is absorbed by the land (compared to water). Water is constantly moving around, swirling, and mixing in the ocean.On land the dirt just kind of sits there. When the Sun hits the dirt, it heats up the top layer. Not much heat moves into the lower levels of the ground. The heat that the ocean absorbs is mixed with the lower water quickly. That mixing spreads the heat around. At night, while the land cools off quickly, the water at the surface is kept warmer because the water is mixed around with the warmer water underneath. All of this mixing keeps the temperature in the area more constant, not like the land that goes from hot to cold. Water also absorbs more energy, because it is semi-transparent. The ground is called opaque, because you can't see through it. What about that altitude thing? It gets colder when you're higher. That makes sense, but why? At higher altitudes, there is a greater gain and loss of heat. When you're up high there is also a lower pressure. There are actually fewer molecules in the air. Because there are not as many molecules, there is less matter to absorb heat. That fact means the temperatures will change more wildly, from hot to cold. There is less matter to absorb the heat. Clouds affect the temperature too. It's like wearing a windbreaker jacket on a windy day. The jacket traps the heat you give off from your body, keeping it warmer between you and the jacket. That jacket is like cloud cover. It reflects the heat given off by the land. The jacket also reflects heat away from you in the same way clouds reflect incoming heat. The thing to know... Just like a jacket where some heat gets in and some escapes, the clouds don't reflect and keep all the heat, some of it still passes through. OCEAN EFFECTYour distance from the ocean also matters. Southern California is a good example. Near the beach is much cooler than it is just over a small set of mountains. The sea air keeps things warmer at night and cooler during the day. This is because of the atmospheric mixing and local winds that are created.The last idea is one of big ocean currents. Large amounts of heat and energy move every day by the force of the wind acting on the ocean. First you get a long steady wind, like a trade wind. This wind pushes on the surface of the water and the water starts to move... Currents are created. The ocean currents start to swirl and the water circulates across the planet. Generally the ocean is warmer at lower latitudes and colder at higher latitudes. Higher latitudes mean you are closer to the poles. This heat difference also causes the oceans to swirl. Eventually the warmer water from the area near the equator moves up to the poles. As the water moves North or South it gives off heat and warms the atmosphere.
|
|
||||||||||||||||||||||||||||||
Go for site help or a list of earth science topics at the site map!©copyright 1997-2007 Andrew Rader Studios, All rights reserved. Current Page: Geography4Kids.com | Physical Geography | Atmosphere Basics | Atmospheric Temperatures |
|||||||||||||||||||||||||||||||
|
|
|||||||||||||||||||||||||||||||
