Global Circulation
Air is something that we all take for granted. We breathe it every day, we look through it, we pollute it. Most of the time, we don’t even notice it. But it can quickly make its presence known when wind is involved. Wind, in general is just moving air, and although in its stationary state it may seem harmless, once started, it is a force to be reckoned with; it can uproot trees, lift roofs of buildings, and generally wreak havoc. It is caused by differences in air pressure within the atmosphere, and the driving force behind all of that is the solar radiation.
Earth is almost spherical and because of its tilt, the sun’s rays hit the area near the equator at an almost right angle, while the areas further away are hit at a smaller angle. This means that the concentration of heat received at the equator is higher, and therefore the air warms quicker there than in the pole-ward regions. The air molecules expand and lift when they are heated, and that, coupled with differences in temperature sets the atmosphere in motion in a massive global chain reaction. The air lifted from the equator creates a low-pressure zone, and is replaced by winds from higher-pressure zones and then in turn, something has to move the air toward them. This air movement is affected by many factors, which makes it even more complicated and harder to understand, but scientists have come up with idealised models of general circulation.
They separated the sphere into three belts, or cells north and south of the equator – the Hadley cell ranging from the equator to about 30° N and S, the Ferrel cell from about 30° to about 60° N and S and the Polar cell from about 60° N and S toward the poles.
The polar cell is a relatively simple system....
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...nfall deficiency. While the eastern and southern parts receive an ample amout of rainfall during the onset phase, while the northwestern part suffers from a shortage of rain because of a heat low circulation over the region.
Summer Monsoon – Withdrawal Phase (September – November). Summer monsoons usually withdraw the way they cam, but in the reverse direction, although it happens very gradually – it is marked by a weakening in the heat low over the subcontinent, a reversal of the wind from southerly to northerly and a decrease in rainfall. This brings cooler and drier air from the north. It moves very quicly in the beginning, but then slows down after withdrawing over half the subcontinent. Winds from northeast start intruding and cause some more rain to occur in the withdrawal phase.
Works Cited
Ramage, CS (1971) Monsoon Meteorology. Academic Press, New York.
The following is a report on Australian drought situation. It will identity the definition of the drought, describe the causes of drought, represent impact of drought in Queensland and introduce management to help farmers cope with future drought occurrences.
There are numerous stages that take place simultaneously in the hydrologic cycle and this includes evaporation. This is when the water alters from a liquid state into a gas. The damp air from the water rises into the atmosphere and when it cools, the vapor condenses and shapes into clouds. But those billows are not the only form the vapors make; it can also materialize as dew, fog and mist, which blanket the Earth, characteristically on a rainy or humid day. Evaporation takes place when water changes from a liquid state into a gaseous state, and ascents out of the pores of the earth and into the atmosphere as a vapor (“How”). While evaporation is taking place, condensation is also occurring. When the temperature in the air plunges, the clouds become heavy and as a result they relieve themselves of the extra weight, which is called precipitation. This produces rain, hail, snow and sleet, conditioned upon the temperate. As the precipitation falls, it enters the surface of the ground and percolates into the soil, which is called infiltration. The more porous the land is, the more the infiltration can take place. However, the ground cannot hold all of that water and floods. The excess rainfall, which is also called runoff that has not been absorbed makes its way into bodies of water, such as small ponds, rivers, lakes and parts of the ocean (“Summary”).
First is a description of the greenhouse effect. The earth’s atmosphere has four layers, or zones, with each having distinct differences in temperature. The troposphere is the first layer surrounding the earth. Within this layer air is continually circulating and moving heat and moisture around the earth. The troposphere is denser than the other layers due to the fact that gravity keeps the majority of air molecules near the earth. This is about 75 percent of all the atmospheric mass. It is also the warmest layer (Cunningham & Cunningham, ...
Surface current are found in the upper four hundred meters (400m) and makes up about ten percent (10%) of ocean (Briney, n.d.). Surface ocean currents are as a result of friction between the water and atmosphere interface. The wind exerts a force or stress to the ocean surface and causes the water to move. The winds that most affect the oceans’ currents are the Westerlies which produce belts of ocean currents that flow east in the mid-latitude and the Trade winds which generate currents that flow to the west in tropical latitudes. These winds are mainly a result of warm air from the tropics moving towards the poles. The direction of the current is not the same as the direction of the wind but it is deflected at a forty five degree angle. This deflection is resulted from the earth’s rotation on its axis called the Coriolis force/ effect. Coriolis force and constrains by continental land masses cause surface currents to develop into an alm...
The currents at the surface of the ocean are split in to two categories, tidal currents and surface currents. Tidal currents occur around land masses and are influenced mainly by the gravitational pull of our sun and moon. They change rapidly but predictably and contribute to surface currents. Surface currents occur over different areas of earth’s ocean. Two main factors affecting the surface currents are wind and the Coriolis Effect. The Coriolis Effect explains how the rotation of the earth seems to cause a deflection of anything moving above the earth’s surface. It is this effect that causes winds and water in the northern hemisphere to appear to deflect to the right and in the southern hemisphere to deflect to the left. One of the major surface currents is the Gulf Stream. Water in around the Caribbean is warmed by the sun and then carried north and east along the coast North America. These sun warmed waters release their stored energy into the westerly winds and Northern Europe benefits by having a much milder winter than t...
diverse change in weather patterns caused by the jump in temperature worldwide, as well as
Wind power is another form of solar power. Wind isn’t only a clean fuel source, but it is one of the most inexpensive e alternative sources of energy. Just as long wind continues to blow and the sun shines then wind power can produce energy to send to many different areas. There aren’t many locations that have continuous wind. And because of that the widespread development of wind power isn’t as great as it could be. Although there are more advantages than disadvantages when it comes to this energy source, the disadvantages should be taken just as seriously. Wind power can harm animals, there was a study that stated birds were coming in contact with turbines and dying. For many people the noise from the turbines is unbearable, and that’s something else that should be taken into
Hurricanes get their start over the warm tropical waters of the North Atlantic Ocean near the equator. Most hurricanes appear in late summer or early fall, when sea temperatures are at their highest. The warm waters heats the air above it, and the updrafts of warm, moist air begin to rise. Day after day the fluffy cumuli form atop the updrafts. But the cloud tops rarely rise higher than about 6,000 feet. At that height in the tropics, there is usually a layer of warm, dry air that acts like an invisible ceiling or lid. Once in a while, something happens in the upper air that destroys this lid. Scientist don not know how this happens. But when it does, it's the first step in the birth of a hurricane. With the lid off, the warm, moist air rises higher and higher. Heat energy, released as the water vapor in the air condenses. As it condenses it drives the upper drafts to heights of 50,000 to 60,000 feet. The cumuli become towering thunderheads. From outside the storm area, air moves in over the sea surface to replace the air soaring upwards in the
First and foremost, unlike power plants that rely on combustion of fossil fuels, wind turbines do not produce atmospheric emissions. Strangely enough, wind is a form of solar energy. Winds are caused by the irregular heating of the atmosphere by the sun, the variations of the earth 's surface, and rotation of the earth. This wind flow, or kinetic energy, when "harvested" by modern wind turbines, can be used to generate electricity. There is an abundance of wind to meet our needs, “the potential of [the total] wind power [in the world] is… 20 times more than what the entire human population needs” (Maehlum). Currently, wind power is one of the lowest-priced renewable energy technologies available, costing between four and six cents per kilowatt-hour, depending upon the wind
Air pollution is a type of pollution that can severely damage our environment as well as the earth’s atmosphere. Air pollution occurs all the time when the air contains many substances ...
a change in the water cycle. Some places may experience more rain. Warmer temperatures will
The thermohaline circulation cycle (THC) delivers heat to the North Atlantic. In the winter the heat from the water is released into the eastward moving air masses like the Gulf Stream, thereby warming much of western and northern Europe. Cooling in the North Atlantic increases the density of the 'upper ocean water' to the point at which it becomes so dense that it sinks to the bottom and flows south towards the Antarctic, forming the 'lower limb' of this conveyor belt of North Atlantic Deep Water (NADW) (1583 Broecker).
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