The Greenhouse Effect: Fact or Fiction

[MrMacphisto]

As has been discussed in other threads, the greenhouse effect is a controversial topic among Americans. While much of the First World believes in this idea, America seems reluctant to accept this theory. (Evolution comes to mind as an ideological parallel to this phenomenon of difference of opinion.) The point of this thread is to discuss the proof and debatability of the greenhouse effect.

My starting point is.... Most people agree that the Earth is in a warming phase when it comes to the average annual temperature rises in the last few decades. My argument is that the greenhouse effect is a valid theory because we have seen relatively dramatic increases in these global temperatures and dramatic decreases in the polar ice caps. While the Earth has gone through Ice Ages and warming phases in the past, the greenhouse effect is accelerating the timeframe of these changes. In other words, if the greenhouse effect continues to grow in strength, then an Ice Age could be gradually brought about in the next few centuries as a result of changing oceanic thermal currents. It won't be as sudden as the Hollywoodized "Day After Tomorrow" movie, but it will be a major change for global climates.

[kurchatovium]

The Greenhouse effect is indeed true as too whether it is causing global warming is very debatable. There is a church in Ireland where temperatures were recorded for the past 300 years and indeed a warming trend was discovered. However when matched to carbon dioxide production levels through out the years (carbon dioxide being the most prevalent and worrisome greenhouse gas) there was no correlation. The data did correlate to increased solar spot activity. Solar spots produce violent magentic storms on the sun and bombard the earth with particles. Currently it is thought that perhaps these particles may influence our weather greatly.

Also the magnetic poles of the Earth are undergoing reversal which they do every 200000 - 750000 years. We are currently in a reversal which may leave the Earth with a greatly weakened magnetic field in about 200-2000 years. As this field continues to decline it will allow more particles from the sun to come in. Is this affecting temperature? Will it cause temperatures to continue to rise? At this point no one can say for sure. But it merits investigation.

[asutickler]

I acknowledge that the Earth's temperature has increased slightly over the last century or so... However, I propose that this increase could well be the product of the Earth's natural climate trends. We have only been able to gather reliable data on the earth's temperature for a couple hundred years, which is only a microcosm of Earth's bigger climate "picture," so to speak.

It has not been reliably demonstrated that human activity has increased the Earth's greenhouse effect. The global warming community's main argument is that "humans have increased the amount of greenhouse gasses in Earth's atmosphere since the beginning of the industrial age, and the Earth has recently gotten warmer. Therefore, the increase in temperature is a byproduct of the aforementioned industrial activity." This is a post hoc fallacy that is not supported by actual scientific research.

[New2u]

Mac, I found this website for you that you and some of your posters might be interested in:

http://www.science.gmu.edu/~zli/ghe.html

The website is based at:

Center for Earth Observing and Space Research (CEOSR)
School of Computational Sciences (SCS)
George Mason University
4400 University Dr.
Fairfax, VA 22030
Ph:(703)993-3637

The picture they report is not very comforting and things are not going to improve as time goes on. I know Mr. Bush is very anti-environmental so we know he's not really going to do much in his second term.

[kurchatovium]

I agree with asu really there is just not enough valid information to say for certain that CO2 levels are causing the slight rise in temperature we see. There are so many long term cycles the earth, sun, and moon go thru that effect our lives it is difficult to ascribe any short term effects to one thing or another without a intensive investigation.

[Robace252]

I dont know if this cooralates with this greenhouse subject but I posted this in the other forum as usual no one responed to the meat of this. Is this because I made a point (as usual) and no one can refute it or have an opinion. Or is someone looking into what I found and are trying to find a way to explain it to me. Im not a scientist or know all that much about it, but from logical thinking this does make sense.

got this inforamtion from a science research firm with the EPA, labeled doc#7765-DR2 Habitability of the Earth in future generations

At what point will the planet will become uninhabitable due to fossil fuels being burned is diffcult because its hard to predict how the earth will respond to the impact of human activities on the climate. From ice core data we know that over the past 450,000 years there has been a natural oscillation in atmospheric CO2 levels and average global temperature, with warmer temperatures occurring with higher CO2 levels.

In this time period, until the start of the industrial revolution, atmospheric C02 varied between 200-300 parts per million (ppm). Now, with the increased burning of fossil fuels and deforestation, this level has surpassed 370 ppm, a condition that the earth has not experienced in the last half a million years.

The earth has had in the past levels of CO2 much higher than the present 370 ppm and is believed to have helped the Earth evolve into the life giving planet we exist on today.

There are also concerns about the volcanic eruptions and natural gases emitting from the earth that actually put more materials into our atmosphere than all of the man made pollutants combined.

Pinatubo and similar volcanic eruptions spew massive amounts of materials into the atmosphere. However, the particular materials ejected normally have the net effect of cooling the Earth, rather than warming it. The volcano only has a global effect when the eruption is powerful enough to send its plume into the lower stratosphere, in regions where there is relatively little mixing and turbulence. In a short time the heavier particles fall out and most of the gases chemically convert to aerosols. However, the remanents can persist for years and spread over most of the globe, acting principally to reflect sunlight and thus cool the Earth. In the case of Pinatubo the cooling lasted for about a year, during which time the stratospheric contamination was visible as faint pink shading just after sunset on the clearest evenings.

So as the earth heats due to CO2 levels rising in the atmosphere it seems as if the planet has what can almost be described as a "fail-safe" and "human proof" way to cleanse itself every 10 to 20 years when a major eruption occurs. There is currently scientific studies ongoing in the arctic regions to attempt to map the precise temperature changes that happen when a major eruption occurs and how this settles the global warming by natural means.
This could be a way that humans in the future can undo any damage if any that has been done by fossil fuels.

Again Im assuming this report was hashed togeather by many scientists with who knows what on their minds and who they were being paid by (US Govt.) but I think scientifically it makes some sense.

Please, someone..anyone...respond scientifically to this...I really am confused and dont know.

[kurchatovium]

There are so many natural cycles occuring it is often difficult to assess things accurately. Regretably many are willing to do things unaccurately. The Earth precesses about itself every 26,000 years, the magnetic poles reverse every 200000-700000 years, the moon is clowing down the earths orbit, sunspot activity is on the increase, ice ages are suppose to occur every 20000 to 100000 years, etc Somehow one mans can of underarm deododerant pales in comparison to all of this. A single volcano eruption will dump tons of greenhouse gases into the atmosphere more than all the mankinds activity several times over. It also dumps debris though that reflects sunlight and heat back out. Maybe the two negate each other. Maybe not. What I am saying is this a complex problem worthy of a non-political study into the matter.

by the way I would worry much more about an asteroid hitting us than greenhouse gases. LOL but thats just me.

[theshire]

The Greenhouse Effect is an undisputed FACT. However, the fact that it is caused by humans is a myth. There is no even remotely concrete evidence that this is so. As has been said before, the Earth has a natural cooling and warming cycle. Did you know that we are STILL in an Ice Age, for example? That is, there are still large slabs of ice on the planet. And how do you naturally exit an Ice Age? That's right, by a period of warming. Sooner or later the ice caps will melt, and there is absolutely nothing we can do about it, unless we invent some pretty rad technology in the future, which isn't out of bounds, I suppose.

And did you also know that there is a Greenhouse Effect on Venus, and that Mars is currently experiencing Global Warming and scientists can't explain why? Did we cause that, too, I wonder, or is it just a NATURAL THING? And did you hear that a half-degree rise in temperature like they're talking about would do wonders for farmers?

I'd guess a lot of people don't know these things. Let's face it, people: Global Warming is political. By scaring us into thinking we're causing the world to heat up, the authorities can do whatever they like and we will accept it. They can bring in yet more taxes to 'reduce emissions' while at the same time taking more of our hard-earned money. And, of course, they can gain electoral accountability from environmentalist groups.

It isn't a surprise to me that most countries who entered the Kyoto agreement are now saying that:

a) They can't match the recommended emission levels

and

b) They won't work anyway.

The Kyoto Treaty is such a monumental waste of money that I am really glad for America's sake that Goerge Bush rejected it. It would cost more per year than the war in Iraq, and for the same money you could get clean water to everyone on the planet. All this for something we don't have any evidence for.

[drew70]

There is clearly a warming trend, but there is no evidence scientific or otherwise, that supports this trend has been in any way affected by mankind. If the moon revolves around the earth, and the earth revolves around the sun, it stands to reason that the entire galaxy is rotating, revolving or in some way moving through space. It seems like much of the universe operates in a cyclic manner. I believe the warming and cooling trends are cyclic and have absolutely nothing to do with "emissions."

I've actually heard it said that the excessive ferocity of Hurricane Katrina was augmented by the man-made global warming trend, due to fossil fuel emissions. When I hear something that stupid, I never know whether to laugh or cry.

[unit5610]

I largely agree with Kurch and with Drew. There are cycles upon cycles upon cycles of various lengths and degrees and in the rather short time, geologically speaking, that we've been really recording weather worldwide, we haven't scratched the surface about how all of the various cycles work in combination with each other.
That being said, I do think that there's value in the global warming debate, if nothing else to focus some attention on the fact that we really should be taking care of the planet better than we have, and that we should looks for ways to reduce our dependence on fossil fuels. I feel the answer to energy consumption is not to drill up northeastern Alaska for another drop in the bucket, but to really try and reduce our consumption like we successfully did in the mid and late 1970s. Unfortunately, it takes a true crisis (not unlike what Hurrican Katrina will do for hurricane prep) to spur on real action, and I don't think we're there yet with the energy issue.

[kurchatovium]

What I find ironic is no one seems to be paying much attention to more serious threats that actually can and will happen. There is an island in the Atlantic from which a large chunk will fall into the ocean creating a massive tidal wave which will devastate much of the east coast (timeline next 50-500 years ). Yellowstone will likely erupt as a supervolcano wreaking havoc on much of the US and much of the world as well (timeline next 100-??? years). An Asteroid will at some point most likely hit the earth there is one likely to intersect with us in 2080 though predictions now are not so accurate as to make this a certainity. I guess I am saying there are enough real threats to work on without inventing imaginary ones. Just my thoughts though. :D :D

[BigJim]

Global warming is a fact, but I believe industrial polution has little or next to nothing to do with it. I'm quite sure it doesn't help, and it certainly fucks up ecosystems, but global warming would be happening right now irrespective of greenhouse gasses.

[Ticklish9's]

Did you know that we are STILL in an Ice Age, for example? That is, there are still large slabs of ice on the planet. And how do you naturally exit an Ice Age? That's right, by a period of warming. Sooner or later the ice caps will melt, and there is absolutely nothing we can do about it, unless we invent some pretty rad technology in the future, which isn't out of bounds, I suppose.

Ice ages, contrary to popular science texts, are generally fairly localized affairs. The last great ice age (the one everyone hears about all the time in high school) covered primarily the North American continent, leaving much of Europe and Asia at similar latitudes ice-free.

The recession of an ice age is the removal of glacial buildup to those boundaries prior to the ice age - generally within the confines of the arctic circle. The burdon of proof generally indicates that there is a fairly consistent glacial cap in the polar regions of varying sizes, though of course nobody was around to check it out until recently.

My point is, to say that we are currently in an ice age isn't really accurate. Following general trends we are about due to enter one, but there's a wide margin of error for the cycle's shift-onset (thousands of years is no big deal on a geological scale, but in geopolitical terms it's an eternity).

And did you also know that there is a Greenhouse Effect on Venus, and that Mars is currently experiencing Global Warming and scientists can't explain why? Did we cause that, too, I wonder, or is it just a NATURAL THING? And did you hear that a half-degree rise in temperature like they're talking about would do wonders for farmers?


The Greenouse Effect on Venus has persisted for millenia. It's a condition known as "runaway greenhouse atmposphere," in that the planet's atmosphere has become so laden with temperature-opaque gases that it simply continues heating up to incredible temperatures. The natural means of filtering out greenhouse gases on Venus either operate to slowly or too ineffeciently to counter the large output of Temp-Opaques from the heavily volcanic planet's interior.

I've not heard that Mars is experience a planet-wide warming trend, but I'll admit I've not been following the science pages as strictly as I once did. Given Mars' wispy atmosphere (it's gravity is too low to hold on to much atmospheric gas) it's difficult to retain heat, but given the sun's gradually increasing brilliance over it's lifespan, one can expect a certain increase in temperatures.

However, I find it unlikely that there is enough temperature data for Mars from a long enough spectrum of time to make any real assessment of climate trends.

[BigJim]

For those of you who subscribe to the "localised ice-age" theory, what do you think of the Earth Crust Displacement idea?

[Ticklish9's]

For those of you who subscribe to the "localised ice-age" theory, what do you think of the Earth Crust Displacement idea?


The biggest problem I have with it is finding a mechanism that could have triggered such a dramatic and sudden (geologically speaking) shift in topology. Hapgood's proposed solution - glacial accumulation triggering an instability - seems unlikely to me, although not impossible. I'll also admit that my understanding is incomplete.

My Grandpa (a physicist) believes that a weakening magnetic field (due to a pole shift) could reduce the hold that the inner core (of metals) has on the lithosphere, allowing the crust to "coast" over the semi-liquid layers. This is possible but difficult to prove.

ECD itself seems entirely logical to me, if in need of some "fleshing out."

[kurchatovium]

Hi 9's. Your grandpa is a wise man. The poles are in the process of reversing currently and should be at their weakest in perhaps a few hundred to few thousand years. How this effects the enviroment is perhaps quite complicated. It might well do as your grandfather has suggested, but it will also allow more particles emitted by the sun (especially during solar flares) to bombard the Earth. How this will effect the atmosphere and the weather is anyones guess. I think it may serve to raise temperatures as temperature readings for the past 300 years or so correlate well with sunspot activity and sunspot activity correlates well with solar flare activity. Just my thoughts. :D

[Ticklish9's]

Hi 9's. Your grandpa is a wise man. The poles are in the process of reversing currently and should be at their weakest in perhaps a few hundred to few thousand years. How this effects the enviroment is perhaps quite complicated. It might well do as your grandfather has suggested, but it will also allow more particles emitted by the sun (especially during solar flares) to bombard the Earth. How this will effect the atmosphere and the weather is anyones guess. I think it may serve to raise temperatures as temperature readings for the past 300 years or so correlate well with sunspot activity and sunspot activity correlates well with solar flare activity. Just my thoughts. :D


He's one of the wisest I know. :)

You're quite correct as to the unknown effects that polar reversal may entail. Logically it is quite possible that more of the solar wind will reach the Earth's surface, and as you said, the effect this may have on the atmosphere and weather is unknown. I think it likely that temperatures will continue to climb due to a combination of increased solar radiation (the sun is likely 30-40% brighter than it was during the reign of the dinosaurs, 65+ million years ago), increased transparency in the atmospheric and magnetic shields, and heat pollution from increased human traffic.

That last bit is the controllable part, and no matter your stance on human impact currently, I think it likely that space travel will dramatically increase in the near future, leading to an increase in atmospheric braking, which is a highly temperature intensive process (shedding velocity through atmospheric friction is a translation of kinetic energy almost entirely to temperature energy).

[kurchatovium]

Thanks 9's. :D Personally I am bit more worried about impacts from large asteroids then the global warming thing. Still I think all these things should be studied. :D :D

[Ticklish9's]

Thanks 9's. :D Personally I am bit more worried about impacts from large asteroids then the global warming thing. Still I think all these things should be studied. :D :D


Of the two, I think that global warming is more solvable than an asteroid impact, and thus in many ways an impact is more worrying.

An end to petty nationalism produces an environment conducive to the solution of both above problems and many more, of course.

[BigJim]

So what do you two think of the possibility that the sun's cycle will cause the pole flip and a near total-reducement of the Earth's field in the next seven to nine years?

[New2u]

Of the two, I think that global warming is more solvable than an asteroid impact, and thus in many ways an impact is more worrying.

An end to petty nationalism produces an environment conducive to the solution of both above problems and many more, of course.

ticklish, if an asteroid hits the earth, the progressives will be blamed for that.

[maniactickler]

Of the two, I think that global warming is more solvable than an asteroid impact, and thus in many ways an impact is more worrying.

An end to petty nationalism produces an environment conducive to the solution of both above problems and many more, of course.

Somehow i dont think theres a solution to global warming. unless the liberals can somehow use their awesome powers to effect the sun. :rolleyes:

[kurchatovium]

ticklish, if an asteroid hits the earth, the progressives will be blamed for that.

If an asteroids hits the earth most likely there will not be anyone or anything left to blame anyone. :D

So what do you two think of the possibility that the sun's cycle will cause the pole flip and a near total-reducement of the Earth's field in the next seven to nine years?

BigJim as I understand pole reversal it is a natural phenomenon that occurs every 500000-700000 years. It periodicity varies quite a bit beause it has to do with the way the inner core of Earth floats and moves in the liquid outer core. It has nothing really to do with the Sun's cycles. However the Sun''s cycles do effect the amount of radiation in the form of high energy particles the Earth recieves. It is the Earth's magnetic fileds that protect us from these particles. As the Earth's field declines we will be more vunerable to this radiation. Fortunately there is most likely 200 - 2000 years before this reaches a maximum where the filed will be at an all time low of 10% or so of its current value. I wonder if the decreasing filed is responsible for the increase in hazardous weather it seems we have seen. There is not enough evidence to say anything for certain but it should be investigated.

[New2u]

Somehow i dont think theres a solution to global warming. unless the liberals can somehow use their awesome powers to effect the sun. :rolleyes:

manaic, if they had "awesome" powers then Bush wouldn't be President.

Then again, Bush used his "awesome" powers to get us into a war that's not going anywhere.

[Ticklish9's]

Somehow i dont think theres a solution to global warming. unless the liberals can somehow use their awesome powers to effect the sun. :rolleyes:



While it would be impossible to directly address global warming without some of the aforementioned awesome powers (which I can't say I entirely rule out in the future - to someone from the middle ages, our society does indeed possess some truly awesome powers), it is possible to deal with the problem it presents both symptomatically and holistically - that is, solve the individual problems it creates, reducing its impact, and address the causes of global warming to reduce its onset and extent.

So what do you two think of the possibility that the sun's cycle will cause the pole flip and a near total-reducement of the Earth's field in the next seven to nine years?

I think that possibility is dramatically remote in that time frame (coincidentally, it is the orientation of the rotation of the Earth's solid inner core that dictates the direction and magnitude of the magnetic field effect, not action on the part of the sun). However, you bring up an important point - such reversals are well documented in the geologic past and WILL happen again in the future. What can we do to prepare?

Without knowing the timeframe of the reductive cycle, we can't really know how major a step we'll have to take to comabt the increase in radiation access to the surface. If it's a long enough timescale, evolution will take care of it for us (with possibly painful effects on population and life expectancy, but nothing species threatening). Shifts much shorter in duration will require greatly increased technological response (which, in a sense, is evolution working on overdrive, in that evolution is means of passing survival information on to successive generations and technology enables us to do that through a sort of external genetics).

[kurchatovium]

The timescale is in the 200-2000 year range about for this current reversal where the poles weaken to their miminum before increasing in the opposite direction so evolution will not be a factor. We best get off our collective buts and think about what to do. IMHO :D

[Ticklish9's]

Absence of radiation shelter from one source (the magnetic field of the Earth) will require radiation shelter from another source.


Buildings could be built specially hardened to resist radiation; cities could move underground or underwater; cities could move to orbit, calculated to constantly rotate at a rate that keeps the Earth between the sun and the habitats; the human body could be strengthened against radiation; cell division could be inhibited during times of radiation storms; an artificial magnetic field could be generated around habitable areas or the entire planet; mankind could wilt away and let evolution do the job itself until the pole rebuilt strength.


These all presuppose levels of technology at or near our own (with a few exceptions), and the timeline you proposed. I'm not certain as the validity of that timeline (not that I don't believe you, I simply don't know enough to say I can agree or disagree with the figure you quoted of 200-2,000 years).

[kurchatovium]

I gotta off the Science channel and several internet searches here is a quote from one at worldhistory.com. This one seems to be in between; some put it much faster; some put it farther off (like 7000-10000 years). 2000 seems like a reasonable number IMHO.

At present, the overall geomagnetic field is becoming weaker at a rate which would, if it continues, cause the field to disappear, albeit temporarily, by about 4000 AD.1 Other sources have put the date of field collapse as early as 3000 AD. The deterioration began roughly 150 years ago and has accelerated in the past several years. So far the strength of the earth's field has decreased by 10 to 15 percent. However, one should note that no one knows if field decay will continue in the future. Also, since a magnetic field reversal has never been observed by humans and the mechanism of field generation is not well understood, it is difficult to say what the characteristics of the magnetic field might be leading up to such a reversal.

[kurchatovium]

I just thought of something BigJim I think the sun's magnetic poles are due to reverse as well. Not sure of the time scale or the effects. Interesting thought though. Makes you think just how rare and precious life is. :D

[BigJim]

While it would be impossible to directly address global warming without some of the aforementioned awesome powers (which I can't say I entirely rule out in the future - to someone from the middle ages, our society does indeed possess some truly awesome powers), it is possible to deal with the problem it presents both symptomatically and holistically - that is, solve the individual problems it creates, reducing its impact, and address the causes of global warming to reduce its onset and extent.



I think that possibility is dramatically remote in that time frame (coincidentally, it is the orientation of the rotation of the Earth's solid inner core that dictates the direction and magnitude of the magnetic field effect, not action on the part of the sun). However, you bring up an important point - such reversals are well documented in the geologic past and WILL happen again in the future. What can we do to prepare?

Without knowing the timeframe of the reductive cycle, we can't really know how major a step we'll have to take to comabt the increase in radiation access to the surface. If it's a long enough timescale, evolution will take care of it for us (with possibly painful effects on population and life expectancy, but nothing species threatening). Shifts much shorter in duration will require greatly increased technological response (which, in a sense, is evolution working on overdrive, in that evolution is means of passing survival information on to successive generations and technology enables us to do that through a sort of external genetics).

Do you think it's possible for a field/pole flip to reverse the direction of the axial rotation?

[The Sean Man]

Do you think it's possible for a field/pole flip to reverse the direction of the axial rotation?

If the Doctor is capable of reversing the polarity of the neutron flow with his sonic screwdriver, anything is possible :Hyrdrogen

[BigJim]

If the Doctor is capable of reversing the polarity of the neutron flow with his sonic screwdriver, anything is possible :Hyrdrogen

An interesting fusion of The Real Ghostbusters and Doctor Who. Damn, I hope David Tennant is good.

[Ticklish9's]

Do you think it's possible for a field/pole flip to reverse the direction of the axial rotation?


Not at all.

Axial rotation is a function of inertia - the Earth has been rotating since it's inception and picked up speed as it picked up mass and radius. Since then it has been slowing down very gradually as a result of tidal friction - the pull of the moon and the sun tend to slowly suck energy out of the equation, which comes out of the velocity of rotation. This has already happened entire to the moon, which is why the moon faces one side towards us at all times - relative to the Earth's motion, it is considered "tidally locked." Ultimately, the Earth will be come tidally locked relative to the moon, and presumably, both will become tidally locked relative to the sun over much greater time periods (which would also result in the moon falling into the Earth's gravity well, I believe, as I've just been thinking about how that would work and that seems the inevitable result).

[BigJim]

I would assume then that you believe the Earth has turned anti-clockwise (as viewed from above the North Pole) since its birth?


Can you explain why conventional science says the axial rotation of the Earth is what causes gravity when other laws contradict this?

[Ticklish9's]

I would assume then that you believe the Earth has turned anti-clockwise (as viewed from above the North Pole) since its birth?


Can you explain why conventional science says the axial rotation of the Earth is what causes gravity when other laws contradict this?


I can't say I follow, Jim... axial rotation causing gravity?

Gravity is generated by the mass of the Earth exerting a pull on nearby matter. All particles have a gravitational effect. The Earth has a LOT of particles, and so (relatively) has a LOT of gravitation.

Axial rotation has nothing to do with gravity, to my knowlege, except insofar as it is subject to the perturbations of gravitational influence. Are you sure gravity is what you meant?

[BigJim]

I can't say I follow, Jim... axial rotation causing gravity?

Gravity is generated by the mass of the Earth exerting a pull on nearby matter. All particles have a gravitational effect. The Earth has a LOT of particles, and so (relatively) has a LOT of gravitation.

Axial rotation has nothing to do with gravity, to my knowlege, except insofar as it is subject to the perturbations of gravitational influence. Are you sure gravity is what you meant?

Gravity is what I meant, and I'm pleased to see you don't hold the notion that most scientific authorities I've read do. I've always held that mass attracts to mass and that the rotation of the earth would actually throw things away from it through centrifugal force, rather than pull it down. I mention this because I've heard "mainstream science" say that if the Earth's rotation slowed to a stop everything would float off the surface because gravity would be nullified. Considering Venus rotates slower than it orbits the sun and yet has gravity almost comparable to Earth, I consider this probably the stupidest line I've ever heard.

[Ticklish9's]

Gravity is what I meant, and I'm pleased to see you don't hold the notion that most scientific authorities I've read do. I've always held that mass attracts to mass and that the rotation of the earth would actually throw things away from it through centrifugal force, rather than pull it down. I mention this because I've heard "mainstream science" say that if the Earth's rotation slowed to a stop everything would float off the surface because gravity would be nullified. Considering Venus rotates slower than it orbits the sun and yet has gravity almost comparable to Earth, I consider this probably the stupidest line I've ever heard.



Wow! I've never heard the "float off the Earth" theory but boy am I glad! I couldn't agree more, it sounds completely out of touch with the facts. You've got it exactly right - gravity is a derivation of the interaction of objects with mass.

No respectable scientist would ever suggest that the rotation of the Earth some how generates a gravitational field.

[BigJim]

Do you believe the Earth has only ever rotated in the one direction?

[MrPartickler]

Can you explain why conventional science says the axial rotation of the Earth is what causes gravity when other laws contradict this?

::nerd on::
This sounds like a confusion with <i>centripetal force</i>--the actual force that pulls inward, radailly, towards the (instantaneous) center of rotation of an object in motion--and gravitiy, which <a href="http://csep10.phys.utk.edu/astr161/lect/history/newtongrav.html">Newton's Law</a> clearly defines as purely a function of the masses and radial distance between objects. (Aside: my former physics teacher would chastise me if I didn't point out that "centrifugal" force--the "outward" propelling effect-- is not really a scientific term.)

A simple, but plausible implementation of <i>artificial gravity</i> is often presumed (in science fiction books, movies, etc.--See <i>2001: A Space Odyssey</i>, <u>Ringworld</u> by Larry Niven and the popular video game: <i>Halo</i>) to be employed in the future on space stations. You've probably seen it many times as a large, rotating tube or ring. Anything or anyone "standing" on the inner surface of the rotating ring, would feel like they were in an environment with gravity. (note the force they experienced would be highly sensitive to the rotational speed of the ring, the diameter of the ring, and their own mass of course.) There's a disussion of some of this in more practical, real-world terms <a href="http://www.space.com/businesstechnology/technology/artificial_gravity_041125.html">here</a>.
::nerd off::
:p

[kurchatovium]

The axial rotation of the Earth is slowng down this has nothing to do with pole reversal, it is the tidal effects of the Moon against the Earth. This too will most likely effect weather and other earthy phenomena as time passes. :D

[mark 19]

Okay I confess that I haven’t read all of the posts on this thread as I just don’t have the will power :D (read most of the first page and then this one) but as the only 2 A-Levels I got where Physics and Environmental Science I thought I should post to this thread and here goes,

The axial rotation of the Earth is slowng down this has nothing to do with pole reversal, it is the tidal effects of the Moon against the Earth. This too will most likely effect weather and other earthy phenomena as time passes. :D

This is entirely correct however as it has been happening for millions of years and its affect each individual year is tiny its not worth worrying about for some time yet to come. In fact I think this year is having an extra second added to it to account for this slowing (at least I’m pretty sure its this year if not then it’s soon anyway)

Gravity is what I meant, and I'm pleased to see you don't hold the notion that most scientific authorities I've read do. I've always held that mass attracts to mass and that the rotation of the earth would actually throw things away from it through centrifugal force, rather than pull it down. I mention this because I've heard "mainstream science" say that if the Earth's rotation slowed to a stop everything would float off the surface because gravity would be nullified. Considering Venus rotates slower than it orbits the sun and yet has gravity almost comparable to Earth, I consider this probably the stupidest line I've ever heard.

I agree centrifugal force (which you my be interested to know has now been deemed rubbish and replaced by centripetal force by the scientific community, essentially the same thing but under a different name (crazy if you ask me)) has nothing to do with gravity. And although they refuse to teach it in A-Level physics as it is just that bit to theoretical gravity is to do with gravitons which are to do with mass (mass being like an energy store and graviton a means of energy transfer from the quantum physics perspective). In other words atoms emitting gravitons like atoms in a star (or more accurately there electrons) emitting photons (light).


And finally as I’m getting tired, The original topic:

The Greenhouse Effect: Fact or Fiction

The Greenhouse Effect is essentially global warming which is what allows life to exist on earth as we are to far away from the sun for it to heat the earth this much (if you want to do the maths just for fun(because I don’t) then model it by using the Earths closest distance to the sun in its orbit as a radius then calculate the surface area of the imaginary spear around the sun at that distance to get the intensity of light reaching to earth when combined with the energy output of the sun and half the surface area of the earth).

We know that global warming exists and that it is caused by particular gasses. However there are many other factors that affect the earths temperature and its not CO2 alone causing the “accelerated greenhouse effect” (the thing that is really being debated here). What I find annoying is that water vapour is by far the biggest green house gas but as it’s a vapour not a gas it seems to get ignored unlike CO2 which whilst being the worst greenhouse gas in terms of the amount in the atmosphere is not the most effective heater, or the most damaging or the one that remains in the atmosphere the longest.

In short I do think we should cut emissions from the burning of fossil fuels however this is only partly due to our contribution to the accelerated greenhouse effect and is mostly because I recognise fossil fuels such as oil will run out one day (not to many decades from now) and we use it for a lot of useful things that I don’t want to do without eg. Plastics (look around you how many thing are made of plastic parts of your computer for a start). And as cleaner (and renewable) energy sources are available I think we should use them instead as it will ultimately have an affect on us eg. Photochemical smog over LA (not pleasant)

p.s. anyone who had the will power to read my long and sketchy response the whole way through has my respect as I know I wouldn’t have!
:rolleyes:

[kurchatovium]

This is entirely correct however as it has been happening for millions of years and its affect each individual year is tiny its not worth worrying about for some time yet to come. In fact I think this year is having an extra second added to it to account for this slowing (at least I’m pretty sure its this year if not then it’s soon anyway)

The effect is small but not as small as you might think ( the earths day was at one time only 10 hours LOL ) and more importantly these small effects have large consquences on weather patterns. I would not minimze any of these factors. We need to understand them all better.

[mark 19]

The effect is small but not as small as you might think ( the earths day was at one time only 10 hours LOL ) and more importantly these small effects have large consquences on weather patterns. I would not minimze any of these factors. We need to understand them all better. on a larger time scale true but in the past few centuries (when man has been making any significant contribution to global warming) a couple of seconds in rotation will have little impact in comparison to other factors. Although I agree that more research is needed in all areas and especially in to synergistic factors.

[kurchatovium]

The effects on global warming are granted most likely minimal, however there are many other factors here to consider. Too numerous to mention.

Overall weather seems to be getting worse though it might be a random trend. However I wonder if there are simple factors that might produce catastrophic effects. They are mathematical anomalies in which insigificant changes produce extreme results (sometimes called Strange Attractor Theory). I use to study these in physics for a bit they are quite amazing equations. A few seconds in one these equations can make a big difference. Is the rotation of the earth one of them? I can not say. I think we had best darn well find out though. All things should be considered I think and then ruled out as research dictates. An open mind is the best weapon we have I feel.

[mark 19]

True, an example of a small change causing a big effect (although probably not what you had in mind),

If the acidity of water in a stream rises slightly it can mobilise heavy metals lying in the riverbed which then flow to a reservoir endangering a city of people as most filtration plants don’t filter for heavy metals.

Not that I’m trying to scare people but I don’t like the sound of this (I suppose a better example would be the charge on an electron effecting the formation of the universe but that’s not so fun as there’s little risk of it changing). Anyway getting back to the point the only real impact of a couple of seconds slowed rotation is the amount of extra energy that can be transferred in that time and things like sunspots have a greater effect than this on energy transfer a regular basis. Still I’m open to it having other effects I haven’t thought of after all not an area I can claim massive knowledge about in relation to weather patterns. :)

[kurchatovium]

There is a field of mathematics called Catastrophe Theory that deals with factors that produce sudden large changes as well. Like why a heart attack happens at a certain time. Not sure if this would be a useful tool for examining these phenomena and maybe deciding what is or is not important.

[venray]

The answer to global warming can be found here........

http://www.venganza.org/

[kurchatovium]

Darn pirates. :sowrong: ( ;) :p )

[Cosmo_ac]

The answer to global warming can be found here........

http://www.venganza.org/

My god....it all makes sense now...what have we done?
In our pursuit to rid ourselves of Pirates, we have disrupted the natural eco-balance, and we have began a distructive cycle that will eventually destroy our world. Fate forces our hand. We MUST create more pirates.

The remaining pirates of the world will be captured, and brought into captivity (to protect this dying breed from poachers who take their eye patches, peg legs, and hooks, and then leave the rest of the corpse to rot in the sun, unlike the native Americans who had a million uses for Pirate's carcus and made sure nothing went to waste) and made to breed. As the years go by, the number of pirates will increase, and after tagging, will eventually be released into the wild.

After a short period of adjustment, with some help from the local governments increasing pressure on officials to take bribes and "look the other way" they will be able to survive by themselves in there natural habitat of carribean waters and hard liquor infested bars.


And so, we might be able to give ourselves a chance.


Long live the Pirates!!! :D

[venray]

Arrrrrrrrrrrrrr.........!

http://img6.imageshack.us/img6/8519/pirate6ip.jpg

[MrMacphisto]

LMAO... Venray, you are the man.

[BigJim]

Anyone seen Dodgeball lately? :D