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1、为什么飞机从东向西飞比从西向东飞的时间要多因为地球在转(不对)我有想过这一点,但是飞机的速度是以地球为参照系的啊,即使按你的理解,那也应该是 由东向西更快才对嘛。不是地球自转引起的,而是喜玛拉亚山形成的大气流,他的方向是从西向东流动,造成飞 机向东走要快于向西走。我们可以设想飞机如果在天上不动,由于地球的自转,飞机是背 离目的地的。飞机由东向西飞和由西向东飞所用的时间为什么不同?比如上海飞成都要3小时20分, 而成都飞上海只要2小时20分。地球是自西向东自转的,那么从东往西飞的飞机应该是和地球的自转方向逆向飞行, 所用时间应该比从西向东的顺向飞行所用时间短才对啊!有朋友能从理论的角度帮忙 解释
2、一下吗?为什么飞机从东往西飞比从西往东飞花的时间长?想了半天没有明白,由于地球自转,不 是应该反过来么?实际上,飞行速度的差异并非是直接由于地球自转引起的,而是地球的自转引起地球上方 大气向一个方向运动,而大气的运动使得飞机相对地面的速度产生差异。由于地球表面受到光照射的角度不同,在赤道所在的热带地区,大气被加热上升,形成热带低气 压带、而极地由于冷,空气下沉而形成极地高气压带,同时,在副热带地区由于空气下沉形成副 热带高压带,而在副极地地区由于北上或南下空气遇到冷空气抬升而形成副极地低压带。那么, 由于气压的不同,从而使气压带之间有空气流动,比如空气就从副热带高压流带向副极地低压带。 然而由
3、于地转偏向力的作用,空气并不能沿着经线方向流动,而是会偏转一个角度,由此,就会 在副热带高压带和副极地低压带之间,形成一片西风带(称为盛行西风或中纬西风带)。Subtropical jet stream倾I ?无克Pl Jokr.ccjrn龙L * *槌地高气压带 化二-虹粗地东风明极地低压带盛行西风JH的带高压带/ / /东北信风己.骚iHttH压带_尸、未南at风-带高气压带U.*、* X盛行西风制极地低r压带极地东风r =极地高气嘛西风带的位置涵盖了我国以及欧亚大陆的大部分区域。在西风带地区的平流层下部,由于对流层气流与其相互作用以及高海拔的太阳加热作用,使得对 应地区的平流层下部产生一
4、条数百公里宽的西风带,这一风带被称为高速气流带Jet Stream), 在平流层底、平流层顶飞行的飞机正是受到这一风带的影响而产生速度的差异。同时,飞机在飞行过程中,具有一个经济速度(就是相对来说单位飞行距离中油耗较低),这一 速度是相对空气的速度,而不是相对于地面的速度,这一速度也被称作空速。因此,当飞机以经 济速度进行飞行时,实际上相对地面的速度(地速),是飞机的空速和大气相对地面速度的和速 度。因此可见,对于飞行在欧亚大陆上空的航线来说,大多要受到高速气流带的影响,因此在空速一 定时,从东向西飞行的地速要慢于从西向东飞行的地速,因此,使得飞机从东往西飞比从西往东 飞花的时间长。当然,如果
5、在其他风带飞行,情况就会不一样了。为什么飞机向东飞比向西飞快呢?比如:北京飞迪拜要10小时,迪拜飞北京只要7小时。与同事闲聊的时候,说道这个话题。几年前就产生这样的疑问,看了相关的解释,知 道这不是直觉上地球自转的结果,而是平流层的西风带的影响。同事不信,让我找出 相关解释,这里引用一下英文版的,顺便学下英文吧。Why do airplanes take longer to fly West than East? HYPERLINK /question.php?number=607 /question.php?number=607Can you please tell me what fact
6、ors cause airplane times to differ between travels to east and to west.Its interesting that you ask this - I am directly experiencing it right now as I sit on an airplane from the UK. It took 5 hours to go West-East on this journey, but is taking about 7 East-West. The reason for the difference is a
7、 atmospheric phenomena known as the jet stream. The jet stream is a very high altitude wind which always blows from the West to the East across the Atlantic. The planes moving at a constant air speed thus go faster in the West-East direction when they are moving with the wind than in the opposite di
8、rection.Every planet has global wind which are mostly determined by the way the planet rotates and how evenly the Sun illuminates it. On the Earth the equator gets much more Sun than the poles. resulting in warmer air at the equator than the poles and creating circulation cells (or Hadley Cells) whi
9、ch consist of warm air rising over the equator and then moving North and South from it and back round.The Earth is also rotating. When any solid body rotates, bits of it that are nearer its axis move slower than those which are further away. As you move north (or south) from the equator, you are mov
10、ing closer to the axis of the Earth and so the air which started at the equator and moved north (or south) will be moving faster than the ground it is over (it has the rotation speed of the ground at the equator, not the ground which is is now over). This results in winds which always move from the
11、west to the east in the mid latitudes.All of the global wind patterns are illustrated in the below diagram taken from the AmherstAstronomy Association Website.You say that wind not the Earths rotation, causes the differences in flight times to the east or west But what causes the headwind and tailwi
12、nd? Maybe high up, away from the Earth, the rotation of the atmosphere is lagging behind relative to the rotation of the Earth. You call it a wind, because it is movement of the air relative to the Earths rotation. So maybe, the difference in travel time is still explained by the rotation of the Ear
13、th?( HYPERLINK /question/atmosphere/q0117.shtml /question/atmosphere/q0117.shtml)You must be referring to several past questions weve answered on differences in flight times between Los Angeles and Bombay, London and New York, and California and Hawaii. In all of those discussions, we explained why
14、flying to the west takes longer than flying to the east and how it is the effect of the wind, and not the rotation of the Earth, that causes these differences.Now your theory might have some merit if not for one simple fact. If what you say is true, then the wind should blow in the opposite directio
15、n of the Earths rotation since the wind is lagging behind. But in reality, the Earth rotates to the east and the winds over most of theplanet blow to the east as well. These winds are called the Prevailing Westerlies since they blow out of the west and to the east. Furthermore, the Earth rotates fas
16、test at the Equator, so according to your theory, this region is where the winds should blow the hardest. But as you can see below, the region along the Equator is referred to as the Doldrums because there is essentially no prevailing wind in this area.Prevailing windsSo what does cause the wind to
17、blow in a given direction? While the Earths rotation does play a role, it is a somewhat indirect one. The primary factor that affects the formation of winds is differences in atmospheric pressure. As is true throughout nature, any fluid will try to move from a region of high pressure to a region of
18、low pressure. The principal causes of these differences in pressure are related to the absorption of heat due to solar radiation.Heating of the atmosphere will obviously vary with time of day and location on the Earth. For example, the mid-latitudes towards the Equator receive much more solar radiat
19、ion than do high latitudes near the poles. As air is heated, it rises creating regions of lower pressure.Air from regions of higher pressure is then pulled into these low pressure zones creating wind. We feel this effect most forcefully during the winter months of the Northern Hemisphere. The warmer
20、 air of the mid-latitudes rises creating a low pressure, but the colder, denser air of the Arctic regions is at higher pressure. The pressure difference between these regions of warmer and cooler air pulls the jetstream further and further to the south bringing that bitterly cold Arctic wind over th
21、e central and eastern United States. This behavior occurs most often from December through February, often creating the sub-zero cold spells and major snowstorms that this time of year is known for. As Spring approaches and the North Pole tilts more towards the Sun, the differences in pressure due t
22、o the absorption of solar radiation become less pronounced and the jetstream stays further north over Canada.An additional effect of solar radiation is its influence on large bodies of water, such as oceans or large lakes. These bodies of water also absorb solar radiation but release it at a much sl
23、ower rate than does the atmosphere, or the land. On a local level, this behavior has the effect of creating breezes that tend to moderate the temperature extremes near shore. Land heats up and cools down more rapidly than does water. During daytime, the atmosphere over land becomes warmer thereby ex
24、panding and becoming less dense, and rises. This behavior creates a low pressure region over land that pulls in air from over water, where the pressure is higher. In the evening, temperatures over land drop more quickly than over water causing the breeze to operate in the reverse direction. Similar
25、effects also operate on a global scale so that the distribution of water around the globe has a significant impact on the generation of wind. It is therefore not surprising that the direction of the prevailing winds illustrated above matches closely with the direction of the ocean currents shown below.Ocean currents, blue represents cold water, red warm waterNevertheless, you are correct in that the Earths rotation does play some role in the formation of winds, and therefore has an indirect effect on the difference in east-to-west flight times. The rotation of the Earth crea
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