Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: Titanscape on 04/08/2012 20:45:37
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I know the moon pulls the seas to tides, but does it effect the atmosphere as well?
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It should.
Much of the atmospheric movement, of course, is caused by convection. Then, of course, temperature and pressure causing changes in density.
My question... say you had two bulges, like in the ocean tides. What would the magnitude be? 2 meters? 100 meters? It is quite possible that atmospheric tides would be difficult to detect independently of lunar observations.
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The Sun and Moon also produce tides in the solid rock of the earth, but their height is much less than the height of the sea tides.
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Yes
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If the tidal forces existed, then the pressure of water and air would certainly react, especially during the parade of the planets.
Does the gravity of the Moon create two atmospheric humpbacks, at what speed does the air tidal hump move from east to west? How cyclones and anticyclones manage to move from west to east, at a speed of 50 km / h, wiping the surface of the continents, while the Lunar air tidal wave, moves from east to west at a speed of 1600 km / h.
Are there two air tides in the mountain potholes, per day, does the speed and direction of the wind change, because moving the atmosphere is much easier than water?
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If the tidal forces existed
There is no "if'' here. The laws of physics demand that they exist. The atmosphere has mass. As such, the gravity of the Moon must invariably pull on it.
How cyclones and anticyclones manage to move from west to east, at a speed of 50 km / h, wiping the surface of the continents, while the Lunar air tidal wave, moves from east to west at a speed of 1600 km / h.
Because that 1,600 kilometers per hour you mention is not a wind speed.
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It should.
Much of the atmospheric movement, of course, is caused by convection. Then, of course, temperature and pressure causing changes in density.
My question... say you had two bulges, like in the ocean tides. What would the magnitude be? 2 meters? 100 meters? It is quite possible that atmospheric tides would be difficult to detect independently of lunar observations.
From my understanding, the Ocean tides have a larger effect on the Lunar atmospheric tides than the direct Lunar gravitational effect on the atmosphere. This may have to do with the fact that water is essentially not compressible, while Air is very compressible.
Solar tides are mostly due to the heating of the atmosphere by the Sun and are the largest effect.
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Those types of waves in the atmosphere are called 'gravity waves' (note these are different from the Einsteinian space-time gravity waves). I did a google but couldn't find any reference to tidal gravity waves, but they should exist, but may be swamped by the solar radiation driven ones at the same frequency that Janus mentioned above.
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Does the gravity of the Moon create two atmospheric humpbacks
Convection currents generating winds overwhelm any effect of moon or planets. The lunar effect on the atmosphere is very small and even a bulge of 100m would produce a negligible change in pressure at the surface.
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Any planetary body with a measurable atmosphere , experiencing significant gravitational force from another large body , will have a large atmospheric bulge facing that body . If the former rotates relative to the latter , then it will have atm. tides . If it is tide-locked , but has atmospheric super-rotation , then the tidal bulge will be displaced in the direction of rotation . This will pull on the land & sea bulges , causing a slight torque upon the planet . An incredibly slow rotation will then be induced . Venus is the nearest example , but many red-dwarf planets should also have these glacier-days . The thinner the atmosphere , the slower the rotation . Many terrestrial planets should have century-long days .
Hope your brain is full , Prof. Meg.
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..................Addendum .
No contributor forwarded an estimate to the height of the atmospheric lunar tidal-bulge . I will therefore tender one . Extrapolation from oceanic tidal bulges , time height differential , considering much lower viscosity , indicates ~ 300 to 500 feet . Faster super-rotation would drag this bulge further off center , thus reducing it's height , while increasing it's tidal effects .
P.M.
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........Extrapolation from oceanic tidal bulges , time height differential , considering much lower viscosity , indicates ~ 300 to 500 feet .
Not viscosity, density is the main component you need to consider, so you can’t extrapolate from ocean tides as density varies little with depth in water but exponentially with atmosphere.
Very difficult to measure lunar tidal effects as they are overpowered by thermal effect of daily sun cycle - in the mesosphere the thermal effects can cause movement of up to 50m/s which is quite dramatic.