How much effect does the Moon have on the Earth's climate?

Question

I don't think I've ever talked about the Moon and climate in the same paragraph before. However, I did find an interesting study which suggests the Moon may indeed have cyclical influences on the Earth due to tidal forces on the atmosphere (much like oceananic tides).

"This research has shown that a high degree of correlation exists between the Tidal
Index as determined by astronomical parameters, LOD and atmospheric geopotential height fields. We suggest that this reflects a true relationship between celestial (mostly lunar) gravitation influence on the Earth’s rotation rate and atmospheric pressure fields. There is a 27.3-day and an average 13.6-day periodic oscillation in the Earth’s rotation rate and atmospheric pressure fields. The oscillation corresponds entirely to the change in lunar orbit phases during the Moon’s revolution around the Earth. 27.3 days is the true period of lunar revolution around the Earth (the tropical month of 27.321582 days), and 13.6 days is half of this period." http://www.iapjournals.ac.cn/aas/ch/reader/download_new_edit_content.aspx?file_no=201001130000001&journal_id=aas

I'm fairly certain that current climate models do not take this into account. Do you think this is important for climate science?

Answer 1

Tidal forces are believed to create enough energy on Titan to power volcanic forces albeit they are methane volcanoes, Titan is much colder than Earth, and Saturn has much greater gravity. Still there is a significant amount of energy generated. Do Climate models take it into account? Undoubtedly they don't. I would think that it is a relative minor factor that isn't even considered but it probably joins a long list, some of which may not even be known. Simplistic climate models have been shown to be just that, simplistic. I think that if you are going to make definitive predictions, as alarmists always do, then all factors including this, should be taken into account. We are obviously nowhere near understanding the numerous factors IMO and our assumptions are pretty wild.

Answer 2

The effect of the moon on weather is indirect in that the moon affects ocean tides that can alter ocean currents that can affect weather. Also, the gravitational pull of the moon does produce atmospheric "tides"; however, the effect, while measurable is small and overwhelmed by other atmospheric factors. Another effect, that while known and measured for several decades at least, has recently begun to receive more attention by geologists is the tidal effect of land masses. In particular new satellites that can measure the topology of the earth show unmistakable "ups and downs" due to the gravitational pull of the moon. It has been hypothesized that these small shifts might be correlated with earthquakes and/or volcanic activity.



The atmosphere, being a fluid, is affected by the moon, resulting in an Atmospheric Tide, a wave that propagates through the atmosphere. However, the increase in atmospheric pressure that occurs at the front edge of the wave is so slight that it is hard to detect from the myriad of other waves that are always present in the atmosphere.



The moon has no statistical effect on the weather but there is a minute effect on atmospheric pressure.



"Tides are raised in the earth's solid crust and atmosphere as well as in the oceans. Every body in the universe has some tidal effect, however small, on every other body. This effect is directly proportional to the mass of the body causing the tide but inversely proportional to the cube of the distance between the bodies. The earth's nearby moon is about 2.17 times as effective as the more massive sun in raising tides on the earth, even though the sun exerts a much greater total force on the earth than does the moon. Thus, the moon's proximity explains its dominant role in creating tides." See this link for more details...

http://www.infoplease.com/ce6/sci/A0861550.html



There are atmospheric "tides" but they are mainly due to heating of the upper atmosphere by the sun. They cause a diurnal pressure variation, with the maxima around 10 a.m. and 10 p.m. each day, with minima around 4 a.m. and 4 p.m.



Here is a link explaining this phenomena...

http://www-das.uwyo.edu/~geerts/cwx/notes/chap01/diurnal.html



And here is an interesting fact...atmospheric tides were a factor in the period of rotation of the planet Venus, which has a much denser atmosphere than the Earth. Here is a link to further explain that...

http://www.imcce.fr/Equipes/ASD/Venus/venus1_en.html



However you raise a very good point as I doubt any of these forces are input into the now infamous computer global warming models!

Answer 3

If the Moon were shrinking there would be a miniscule cooling effect on the planet, but a greater influence is being caused by the fact that the distance between the Sun and the Moon is growing, this is causing the planet to cool by approx 0.00000000000000000148°C per year (±33%). Historically the Moon is much more closely tied with out climate. If the giant impact hypothesis holds true then the Moon is created from debris left over from Earth’s impact with it’s twin Theia. Theia is believed to have struck the Earth at an oblique angle and with a velocity of around 4,000 metres per second. The core mass of Theia being absorbed by the Earth and the remainder of the protoplanet and much of Earth’s core and mantle being ejected into space, where it would have been held in orbit by Earth’s gravity. Over a period of a few years the debris would have formed into larger lumps through gravitational attraction, these larger pieces would themselves have coalesced and ultimately created the Moon. This collision would have added enough mass to Earth so as to slow it’s rotation down by four or five hours and knocked Earth sideways upon it’s axis, where it has inclined ever since. This inclination is known as axial tilt or obliquity, it varies over a 41,000 year cycle between an angle of 22.1° and 24.5°. Because Earth is now at an angle, the incidence of solar rays in relation to land and ocean masses has changed and thus the amount of energy received per unit area on Earth’s surface has also changed. Land masses have a higher reflectance than the seas and oceans and absorb more heat energy from the Sun. This changing balance between insolation striking land or water affects the amount of solar radiation the planet absorbs which in turn affects the amount of thermal radiation the planet emits which in turn affects the amount of heat available to be retained in the atmosphere. Returning to the question… One of the most obvious affects of the Moon is that it is one of the mechanisms that governs the rise and fall of tides. We tend to think of tidal motion being something that affects the seas and oceans but it also affects the atmosphere. Just as water is fluid in motion, so too is air (in simplified terms). If the Moon were to be losing mass then it’s gravitational influence on Earth would lessen, the tidal effects would become less pronounced and the speed of rotation of Earth would increase. But the Moon isn’t losing mass. As the Sun burns it converts 4 million tons of mass into energy every second (not quite true but it’s the same effect), this loss of mass means that the Sun’s gravitational pull is very, very slowly diminishing and the bodies within the solar system are moving apart. One of the consequences is that the Earth is moving away from the Sun and the Moon is moving away from the Earth, but only be a few centimetres per year. If the Moon were to be getting smaller, and I’ve never come across anything to suggest that it is, then it’s most probable that this would be the result of compression and not through the physical loss of lunar material. If the Moon were being compressed, it would still retain the same mass and there would be no effect in relation to it’s gravitational influence on our planet or anywhere else in the solar system. If the Moon shrank it’s surface area would be reduced and there would be less moonshine reflecting from the Moon to Earth. Virtually all the heat on our planet comes to us directly from the Sun but there is a very small amount that reaches us by way of reflection from the Moon. This reflected lunar energy warms our planet by approx 0.015°C, more direct heating from the Sun warms the planet by 33°C. The moon has a diameter of 3476000000mm and therefore a surface area of 151,895,234,238,528,000,000mm². If the diameter were to be reduced by 1mm the surface area would then become 151,895,234,151,131,000,000mm². This would be some 0.000,000,000,575,374,081,712% smaller and there would be a corresponding drop in reflected energy being transmitted to Earth, enough to cool our planet by 0.000,000,000,008,630,611,225,690°C. So in answer to your question, if the moon did get smaller it would affect the climate of Earth but by such a miniscule amount that it can be completely ignored. Even if the Moon disappeared completely the effect would still be small, it would be the equivalent of removing just under one years worth of global warming (0.0150°C of the annual 0..0177°C rise in temps).

Answer 4

It has had a profound effect when measured in billions of years. When measured in centuries, it probably doesn't matter at all. It slowed down the rotation of the earth and stabilized the orbit. One made the days shorter and the other would have a profound effect on seasons and other effects described by the Milankovich cycle.

Answer 5

If you want the typical alarmist snickering, continue to ask questions like this...which by the way is a great one. I have to give credit where its due d/dx knows his business: https://answersrip.com/question/index?qid=20080902171539AAHUTfG



Heres some other insights: http://wattsupwiththat.com/2007/10/17/earths-albedo-tells-a-interesting-story

Answer 6

Nope. Climate is concerned with times much greater than 27.3 days.

Answer 7

Have to agree with N-LB; a short term cycle, net effect zero.



From the conclusions;



>>Thus, lunar forcing may be very important to weather

and atmospheric circulation processes. It should be considered in models of atmospheric

circulation and in short- and medium-range weather forecasting.<<



Ok, perhaps this would be of interest to those involved in weather forecasting, but what has it got to do with global warming?



Anyway, to answer your question, though I don't know for certain, I would be very surprised if climate models would take this sort of thing into account. ... and no, it's not important to climate science.



There really is a difference between weather and climate.

Answer 8

Don't know, but I know that using LUNAR energy could be awesome (as in tidal power.)



Anything that exerts that much force on the earth must have an effect, but we know so little about the climate that most of us probably haven't even considered it.

Answer 9

A cycle repeating with a period of 27.3 days and whose sum is zero (no long term increase).





I guess you can easily figure this one yourself out...

Answer 10

"Do you think this is important for climate science?"



I'm not sure climate science is important at all.



It would seem, though, that the influence of the moon's gravity doesn't vary and therefore would not have an effect on climate CHANGE. It is surely true that the climate would be different were it not for the moon.