What is a pressure belt?

Pressure zone-An overview of the relationship between wind zone and climate in pressure zone. Atmospheric pressure is the abbreviation of atmospheric pressure. The pressure acting on any surface due to the weight of the atmosphere is the weight of air in a vertical air column from unit area to the outside of the atmosphere. Because the latitude of the earth's surface is different and the amount of solar radiation received is different, different pressure zones are formed, which is the pressure zone. 1. First of all, there are 7 pressure zones and 6 wind zones in the world. 2. Earth pressure zone (formula): high pressure zone 4, low pressure zone 3: between north and south, high temperature gas turns up, the equator is low, and precipitation is convenient; 30 degrees north and south, airflow deflection, subtropical high, little rain, frequent drought; Polar pressure is low, close to the poles; 60 degrees north and south, extremely low. Seasonal movement of pressure belt 4. Seasonal movement law of pressure belt and wind belt Reason: The direct point of the sun moves back and forth along the Tropic of Cancer every year: north in summer and south in winter. * Features: The area controlled by equatorial low pressure belt and westerly belt is rainy and humid. The area controlled by subtropical high is hot and dry. When the trade winds are controlled, the wind comes from the ocean, which is wet, and from the land, which is dry. (1) Under the influence of the geostrophic deflector, the air diverted northward at the equatorial altitude will eventually move to the westerly direction of about 30 N. (2) The air at the equatorial altitude will continue to flow northward and accumulate at the height near 30 N, so that the air at the height near 30 N will sink vertically, thus forming a subtropical high near the ground. (3) The near-surface air near 3)30° N will be divided northward (north, south) and southward. The southerly airflow deflects to form the northeast trade wind. (4) Sub-polar depression near 60 N. (5) West (southwest) winds prevail between 5)30° N and 60° N; Between 90 N and 60 N, the polar east (northeast) wind and pressure zone-forming pressure zone, the solar radiation obtained at different latitudes of the earth is different. So the temperature changes with latitude, and so does the air pressure. The stronger the radiation, the higher the temperature; The weaker the radiation, the lower the temperature. The lower the latitude, the higher the temperature; The higher the latitude, the lower the temperature. The lower the temperature, the higher the air pressure; The higher the temperature, the lower the air pressure. The atmosphere always blows from a place with high pressure to a place with low pressure, thus forming different pressure zones and wind zones on the earth. Pressure zones-seven pressure zones assume that the earth's surface is smooth and uniform, and the horizontal distribution of pressure is banded. There are seven horizontal pressure zones on the earth, which are geographically divided into equatorial low pressure zone (distributed near the equator), subtropical high pressure zone (near 30 degrees north and south latitude), subtropical low pressure zone (near 60 degrees north and south latitude) and polar high pressure zone (near the north and south poles). (1) equatorial low-pressure belt: It is just like this that a low-pressure belt-equatorial low-pressure belt is formed in the area between the south and north latitudes of 5. (2) Subtropical high pressure area: The air flow rising from the equatorial low pressure area, because the temperature decreases with the height, the air becomes heavier, and it gathers in a large number at a distance of 4-8 kilometers from the ground, and then turns to the north-south direction to spread. At the same time, it is also influenced by gravity, so the airflow goes forward and sinks a little near 30 north and south latitudes, which increases the low-altitude air and pressure, forming two subtropical high zones in the north and south. (3) Polar high pressure area: The north and south poles of the earth and their vicinity are the areas with the highest latitude, where the sun's altitude angle is the smallest, and it receives the least sunlight and heat. The annual temperature is low, the air is cold and heavy, the ground air is abundant, and the air pressure is high, forming two polar high pressure areas, which are caused by thermal reasons. In order to distinguish the above two kinds of high pressure, it should be pointed out that under normal circumstances, in places with high temperature, due to the expansion of the atmosphere near the ground and the accumulation at high altitude, the air density at high altitude increases, and the air pressure there is higher than that around the same horizontal plane, forming a high pressure, so the air diffuses from places with high pressure to places with low pressure around, which reduces the air quality at places with high temperature and the ground pressure, forming a low pressure; Where the temperature is low, the air shrinks and sinks, and the air density at high altitude decreases, forming a low pressure, which is supplemented by the surrounding air, so that the atmospheric quality of the air column in the low temperature area increases and the ground pressure increases accordingly, becoming a high pressure. So the air near the ground is heated, the air pressure drops, the air cools and the air pressure rises. The air pressure at high altitude is usually opposite to the ground pressure. Because of the high temperature, air rises, accumulates at high altitude, and the density increases, forming high pressure; Where the temperature is low, after the air drops, the high altitude density decreases to form a low pressure. This is due to the formation of high pressure and low pressure in the air due to heat. (4) Sub-polar low pressure area: This pressure area is about 60 degrees north and south latitude, and it is a relatively low pressure area because it is between the subtropical high pressure area and the polar high pressure area. In this way, assuming that the earth does not rotate, the above seven pressure zones are formed on the earth. The earth has been spinning. Therefore, the formation of the above seven pressure zones is accompanied by the movement of air. And the direction of air movement always points from high pressure to low pressure. Because the atmosphere tightly surrounds the earth's surface, the atmosphere rotates with the earth from west to east in the process of moving from high pressure area to low pressure area. In this way, the atmosphere is also affected by a force generated by the earth's rotation, which is the earth's rotation deflection force. It always makes the moving atmosphere lean to the right in the northern hemisphere and to the left in the southern hemisphere. In this way, the direction of wind movement is not only from high pressure to low pressure, but also right deviation in the northern hemisphere, and the north wind becomes northeast wind; The southern hemisphere shifted to the left, and the south wind became the southeast wind. The description of the seasonal movement of the pressure belt and the wind belt is correct: a As far as the northern hemisphere is concerned, the position of the wind belt moves northward in summer and southward in winter, which will inevitably lead to seasonal changes in wind direction. C The reason for the seasonal movement of the pressure belt and the wind belt is due to the regression movement of the direct point of the sun, which moves between the Tropic of Cancer and the Tropic of Cancer with the change of seasons, resulting in the seasons of the pressure belt and the wind belt. In spring and autumn, the sun shines directly on the equator, and the equatorial low pressure area is located between 5 degrees north and south latitude on both sides of the equator. From the vernal equinox to the summer solstice, the direct point of the sun gradually moves from the equator to the tropic of cancer. During the summer solstice, the pressure belt and wind belt move about 5 degrees to the north than at the vernal equinox. At this time, the equatorial low pressure belt moves northward between the equator and the north latitude 10; Because the sun's direct exposure to the Tropic of Cancer is very short, and the formation of the low-pressure zone is too late, it is impossible for the equatorial low-pressure zone to move near the Tropic of Cancer. But at this time, the southeast trade winds in the southern hemisphere can blow all the way to the equator, and even some of them can cross the equator, blow to the northern hemisphere, and deflect into southwest winds. From summer solstice to autumnal equinox, the direct point of the sun gradually moves south to the equator; From the autumnal equinox to the winter solstice, it moves south to the tropic of Capricorn. At this time, the pressure belt and wind belt on the ground generally move about 5 degrees south than the autumnal equinox and 10 south than the summer solstice. For example, the equatorial low-pressure belt has now moved southward between the equator and south latitude 10, and the northeast trade winds in the northern hemisphere can blow all the way to the equator, and some of them will be deflected into northwest winds through the equator. Because the pressure belt and the wind belt move north and south with the seasonal changes, the zone between 5- 15, 35-45 and 60-70 in the north and south latitudes becomes the transition zone of the wind belt. The formation of pressure belt and wind belt is the result of global atmospheric circulation. Due to the regularity of atmospheric circulation, the distribution of pressure zone and wind zone on the earth also has obvious regularity. On the whole, pressure zones and wind zones are alternately distributed, that is, there must be a wind zone between the two pressure zones. From the point of view of pressure belts, the seven pressure belts in the world are alternately distributed high and low, and symmetrically distributed north and south with the equator as the axis. The distribution of wind belts is symmetrical with the equator, that is, the trade winds, west winds and polar easterlies in the northern and southern hemispheres. The nature of each pressure zone mainly depends on the movement mode of airflow in the vertical direction, that is, rising and sinking. The place where downward airflow prevails must be a high-pressure area, and the place where upward airflow prevails is a low-pressure area. Among the seven pressure zones, there are three low pressure zones and four high pressure zones. The determination of wind direction is mainly based on the relative position of high and low pressure and the hemisphere (south or north) where the wind belt is located, because the wind always flows from the high pressure area to the low pressure area, which is formed under the action of geostrophic deflection force. The high pressure area must be the divergence area of the wind, and the low pressure area must be the convergence area of the wind. Pressure Belt-Reference [1] Song China Encyclopedia of Middle School Teaching Geography Volume Compulsory Geography of Ordinary High School Curriculum Standard Experimental Textbook [2] Hengqian Education Network /zxdl/Photo/ShowClass.asp? Classic = 48 & page = 3 [4] Geomantic Land /Photo/jctp/200804/303.html [5] Nanxian Education Information /jyzy/ShowArticle.asp? ArticleID= 1 142