Global Warming: Solutions

[raemiel]

Apologies for the double post but this is separate to what my last post was detailing.

If anybody would like some data on the Earth's palaeoclimate I am happy to provide some.

 

[goodman528]

CO2 warming doesn't work quite like that. What happens is that the sun's energy comes through the atmosphere mostly in visible frequencies and strikes the Earth, warming it. The warmed Earth then gives off energy by radiating in much longer wave lengths like heat. CO2 absorbs little energy within the visible spectra, but absorbs a lot of heat within a narrow long wave spectrum. Thus CO2 and other greenhouse gases allow the energy to pass in, but trap it on the way back out. This is good because without that trapped energy we would be quite cold and lifeless, but is potentially bad because too much trapped heat makes things unpleasant.

The debate on CO2 warming is at what point do we reach saturation - in other words, at what point has all the radiation (within that band that CO2 absorbs) actually been absorbed, so that further CO2 has no effect because there is no more of that radiation to be absorbed by the additional CO2? And when that point is reached, will that amount of heat continue to heat the Earth, or will it be offset by other natural feedback phenomena?

There are of course other nasty affects of excess CO2, such as acid rain, increased erosion of stone and soft metals, and ocean acidification. These things to me are more worrisome than the heating effect of CO2; I think we reached saturation for the heating some time ago.

Well, I know that is the official explanation for global warming, but my box is a much simpler way of looking at it. If you put the earth in a box, then you don't care about what goes on inside that box, all you care about is how much heat goes into that box, and how much heat comes out of that box. (More accurately the boundaries of your box is two concentric hollow spheres, the bigger one surrounds everything on earth, the smaller one surrounds the earth's crust, so the bit in between the two spheres is your box. So oil and coal and gas coming from underground, is also being brought into the box.)

(Black Body) Radiation is exactly what you are talking about with these waves. All things gives out waves, the hotter a body is the shorter the waves, because shorter waves has more energy. (Which makes a lot of sense when you think about it, visible light: blinds you when you are hung over; ultra-violet: gives you sun-burn; X-ray: gives you cancer; gamma: could kill you) The sun is 6000C, the earth is 20C, so sun gives short waves, earth gives long waves. The reason why these waves are emitted is to do with the electrons in the molecules moving down energy levels to become more stable. Different molecules has different electron energy level and stability levels. So when CO2 absorbs the waves, it does not re-emit these waves. These waves makes CO2 vibrate and rotate and move faster, but does nothing for CO2's electrons.

I don't think there is saturation for the heating effect of CO2, for a very simple reason: All of the heat that goes from earth into space, is given out as these waves, so there's no shortage of waves to absorb. (Which makes sense because you can ask yourself other than radiation, what other ways of transfering in vacuum is there?) Also, CO2 stays in the atmosphere for a very long time, we may as well assume it to be an infinite amount of time, and if you think back to the earth in the box, because more heat is going in then coming out, the heat inside that box is building up over time. At best you have a linear increase in temperature, at worst you have an exponential curve increase in temperature, but no saturation.

I think the real conspiracy involved with global warming is that all of the documentaries they are making on this subject on both sides are hiding behind vast amounts of stats and figures, and quotes from scientist, etc. As if these guys think the truth is too complicated for the public to understand, that we need scientists to tell us what to think (well, we do, but we need the method and theory, not just the contradicting results). Whereas global warming is very obvious and the only logical conclusion, and the thinking behind it is very very simple.

Ocean acidification is hardly a problem, with all this overfishing, and dumping nuclear waste into the ocean, there will be nothing left for the acid to kill anyway.

 

[ffxfriek]

Solution: realize global warming is not man made.

AMEN thank you

 

[werepossum]

First of all I must apologise as this will be a lengthy forum post, but read through it as I must answer werepossum's challenge to provide examples of when geophysical methods have been utilised to accurately date environmental phenomena.

Since efforts to correlate ice core dating with known dates have been poor at best, I'd rather not put all my eggs into that basket.

That's simply not true, the methods utilised in correlating ice-core dating with dates are very refined. Ice-core dating is the science in this area which gets the most attention but it is not the only technique, nor is it the most far back reaching. Dating of cores of marine and lacustrine sediments provides a much older timescale and is utilised in conjunction with sciences like ice-core logging and stratigraphic fossil assemblages to provide a fairly comprehensive history of temperature and climate variation.

It's not like they use the core retrieved on it's own and preserved air-bubbles in ice is not the only way to determine climatic changes. The whole discipline of palaeoclimate analysis utilises a huge amount of sciences, many of which one would not even have thought could be applied in such a manner. Claiming that the results are 'poor at best' is just a slap in the face to thousands of scientists and illustrates an unenlightened perspective on the subject at hand.

So name for us some projects where the depth of ice for a particular dateable phenomenon was predicted and correctly found? Let's say a particular volcano erupted in 1312 and was well documented - where are the projects that accurately predicted the depth of burial for that layer of sediment? Saying that one unverifiable study is well-correlated with another unverifiable study is all well and good, but if we're to believe the end is nigh and turn over control to the nigh-sayers, I'd like some repeatable evidence that the system of unverifiable studies can be reasonably proved accurate.

As an example, consider the rate of deceleration in the universe's expansion. For decades it was taken as a given that the universe was expanding AND that the rate of expansion was decreasing. Many studies and observations attempted to measure the rate of deceleration with various degrees of success, but no published studies found acceleration. Then we get some instruments in space, take some better measurements, and presto! The universe's expansion is actually accelerating. Now every study and observation measuring the rate of acceleration in the universe's rate of expansion finds acceleration. The moral is that universal agreement in science does not always indicate the right answer. Science blindly followed is not science; it's religion.

The Hatepe eruption of the caldera forming Lake Taupo in New Zealand is a perfect example of this. Information on it can be found at http://en.wikipedia.org/wiki/Hatepe_eruption (I know it is wikipedia but this entry is well referenced). Have a read of the Stages of eruption and Dating the Event sections.

Six distinct sedimentary units are identified in the stratigrapy surrounding this eruption which occured before human habitation of the area. Tsunami deposits have been identified as being associated with the eruption as well. Sedimentary analysis also indicates the eruption expanded the surrounding lake and caused a week long flood.

Initally the event was dated at 130 CE based on carbon dating techniques. This was seen to be a little inaccurate and so geophysical techniques were utilised to identify tephra laminations in the sedimentary record which were sourced from the eruption. The extent of tephra deposits indicates a massive eruptive column and cloud which would have been visible from China and Rome. Records from China and Rome correlate to what would be observed at the time of the eruption and so the eruption can be dated exactly to 186CE.

A different, and much more interesting, eruption of Taupo was the Oruanui eruption. This is the world's largest known volcanic eruption for the last 70 000 years and occured around 24 500BC. Information for it can be found at http://en.wikipedia.org/wiki/Oruanui_eruption

The very shape of Lake Taupo is derived from this eruption as it was so massive. Tephra from the eruption can be up to 200 meters thick in the sedimentary record, and 1 000km away an 18cm ash layer (18cm is still a pretty thick layer in this circumstance) has been identified to be from this eruption.

This eruption occured far before human records and thus dating it relies on geophysical techniques. Techniques utilised would have included been stratigraphic correlation from around the world of sedimentary layers and the fossil record (macro and microscopic), atmospheric and particulate composition determination from ice-cores and geophysical analysis of the areas geomorphology just to name a few.
Note: dating this does not involve radioisotope dating, it is all geophysical.



Right, sorry for that lengthy post. This is not blind following of science and these eruptions are verified and accepted by the scientific community.

Let's try that again. I've put my original request in bold for your review. We are specifically referring to the reliability of ice build-up knowledge. In your first example, geological evidence differed from Carbon-13 dating; the geological evidence was judged more accurate by the writer of the article because of a possible tie-in to a recorded event in human history. Yet what I'm looking for is evidence that science can today successfully predict the depth of a layer in ice before coring it.

This is important because deep ice is under enormous pressure, hundreds of bars. We also know that liquid water is found even at -70C at those pressures. And we know that CO2 is tens of times more soluble than nitrogen and oxygen at those pressures and temperatures. Yet ice core dating assumes that the bubbles found in ice core occlusions are representative of the ancient atmosphere.

So what I am questioning is not science's ability to find one matching testing methodology or even correlating data once they are collected; what I am asking is demonstrated, predicted proof of science's understanding. For instance, take the famous lost squadron that landed on, and was abandoned on, Greenland in '42. Conventional estimates of ice coverage in 46 years were 15 to 20 meters' coverage. The actual coverage was about 80 meters. What I'm saying is, show me where science now understands this process; where someone in print has said "I'm off to core Greenland to 1,200 meters, where I shall find sediment of the Hatepe eruption" followed by print records of that scientist actually finding sediment of the Hatepe eruption at 1,200 meters.

Heck, show me the gas equations for the firn to ice to water transition as precipitation is covered by more precipitation. Show me a model of deep ice explaining gas diffusion and examples of its verification. At least show me why direct CO2 and temperature measurements from the late 18th and early 19th centuries should be thrown out in favor of proxy studies and ice cores. What you've shown me in these two examples are one example of possible partial correlation of a correlating discipline to a datable historical event and one example of inter-discipline correlation without a datable historical event. Both are interesting; neither provide any proof that our current source of knowledge warrants turning over the world's socio-economics to the CAGW crowd.

 

[raemiel]

First of all I must apologise as this will be a lengthy forum post, but read through it as I must answer werepossum's challenge to provide examples of when geophysical methods have been utilised to accurately date environmental phenomena.

Since efforts to correlate ice core dating with known dates have been poor at best, I'd rather not put all my eggs into that basket.

That's simply not true, the methods utilised in correlating ice-core dating with dates are very refined. Ice-core dating is the science in this area which gets the most attention but it is not the only technique, nor is it the most far back reaching. Dating of cores of marine and lacustrine sediments provides a much older timescale and is utilised in conjunction with sciences like ice-core logging and stratigraphic fossil assemblages to provide a fairly comprehensive history of temperature and climate variation.

It's not like they use the core retrieved on it's own and preserved air-bubbles in ice is not the only way to determine climatic changes. The whole discipline of palaeoclimate analysis utilises a huge amount of sciences, many of which one would not even have thought could be applied in such a manner. Claiming that the results are 'poor at best' is just a slap in the face to thousands of scientists and illustrates an unenlightened perspective on the subject at hand.

So name for us some projects where the depth of ice for a particular dateable phenomenon was predicted and correctly found? Let's say a particular volcano erupted in 1312 and was well documented - where are the projects that accurately predicted the depth of burial for that layer of sediment? Saying that one unverifiable study is well-correlated with another unverifiable study is all well and good, but if we're to believe the end is nigh and turn over control to the nigh-sayers, I'd like some repeatable evidence that the system of unverifiable studies can be reasonably proved accurate.

As an example, consider the rate of deceleration in the universe's expansion. For decades it was taken as a given that the universe was expanding AND that the rate of expansion was decreasing. Many studies and observations attempted to measure the rate of deceleration with various degrees of success, but no published studies found acceleration. Then we get some instruments in space, take some better measurements, and presto! The universe's expansion is actually accelerating. Now every study and observation measuring the rate of acceleration in the universe's rate of expansion finds acceleration. The moral is that universal agreement in science does not always indicate the right answer. Science blindly followed is not science; it's religion.

The Hatepe eruption of the caldera forming Lake Taupo in New Zealand is a perfect example of this. Information on it can be found at http://en.wikipedia.org/wiki/Hatepe_eruption (I know it is wikipedia but this entry is well referenced). Have a read of the Stages of eruption and Dating the Event sections.

Six distinct sedimentary units are identified in the stratigrapy surrounding this eruption which occured before human habitation of the area. Tsunami deposits have been identified as being associated with the eruption as well. Sedimentary analysis also indicates the eruption expanded the surrounding lake and caused a week long flood.

Initally the event was dated at 130 CE based on carbon dating techniques. This was seen to be a little inaccurate and so geophysical techniques were utilised to identify tephra laminations in the sedimentary record which were sourced from the eruption. The extent of tephra deposits indicates a massive eruptive column and cloud which would have been visible from China and Rome. Records from China and Rome correlate to what would be observed at the time of the eruption and so the eruption can be dated exactly to 186CE.

A different, and much more interesting, eruption of Taupo was the Oruanui eruption. This is the world's largest known volcanic eruption for the last 70 000 years and occured around 24 500BC. Information for it can be found at http://en.wikipedia.org/wiki/Oruanui_eruption

The very shape of Lake Taupo is derived from this eruption as it was so massive. Tephra from the eruption can be up to 200 meters thick in the sedimentary record, and 1 000km away an 18cm ash layer (18cm is still a pretty thick layer in this circumstance) has been identified to be from this eruption.

This eruption occured far before human records and thus dating it relies on geophysical techniques. Techniques utilised would have included been stratigraphic correlation from around the world of sedimentary layers and the fossil record (macro and microscopic), atmospheric and particulate composition determination from ice-cores and geophysical analysis of the areas geomorphology just to name a few.
Note: dating this does not involve radioisotope dating, it is all geophysical.



Right, sorry for that lengthy post. This is not blind following of science and these eruptions are verified and accepted by the scientific community.

Let's try that again. I've put my original request in bold for your review. We are specifically referring to the reliability of ice build-up knowledge. In your first example, geological evidence differed from Carbon-13 dating; the geological evidence was judged more accurate by the writer of the article because of a possible tie-in to a recorded event in human history. Yet what I'm looking for is evidence that science can today successfully predict the depth of a layer in ice before coring it.

This is important because deep ice is under enormous pressure, hundreds of bars. We also know that liquid water is found even at -70C at those pressures. And we know that CO2 is tens of times more soluble than nitrogen and oxygen at those pressures and temperatures. Yet ice core dating assumes that the bubbles found in ice core occlusions are representative of the ancient atmosphere.

So what I am questioning is not science's ability to find one matching testing methodology or even correlating data once they are collected; what I am asking is demonstrated, predicted proof of science's understanding. For instance, take the famous lost squadron that landed on, and was abandoned on, Greenland in '42. Conventional estimates of ice coverage in 46 years were 15 to 20 meters' coverage. The actual coverage was about 80 meters. What I'm saying is, show me where science now understands this process; where someone in print has said "I'm off to core Greenland to 1,200 meters, where I shall find sediment of the Hatepe eruption" followed by print records of that scientist actually finding sediment of the Hatepe eruption at 1,200 meters.

Heck, show me the gas equations for the firn to ice to water transition as precipitation is covered by more precipitation. Show me a model of deep ice explaining gas diffusion and examples of its verification. At least show me why direct CO2 and temperature measurements from the late 18th and early 19th centuries should be thrown out in favor of proxy studies and ice cores. What you've shown me in these two examples are one example of possible partial correlation of a correlating discipline to a datable historical event and one example of inter-discipline correlation without a datable historical event. Both are interesting; neither provide any proof that our current source of knowledge warrants turning over the world's socio-economics to the CAGW crowd.

I realise that you initially referred to ice-coring but you then (even in the bold section) broadened your question to geophysical correlation.
I quote:
"Let's say a particular volcano erupted in 1312 and was well documented - where are the projects that accurately predicted the depth of burial for that layer of sediment?"

I provided two such projects for you, one of which has been accurately verified with human records and another which has been verified with an acceptible level of certainty. The Oruanai eruption is very well known in geophysical disciplines and is used as a perfect example of stratigraphic correlation and demonstration of sedimentary layering and dating.

Claiming that these dates or events or correlations are not known as certainties and thus are of dubious value means that you must hold this view for all sciences and as such all research is in vain as it is not able to be objectively proved.

I apologise that I cannot provide data on ice-cores specifically but that is not my discipline, instead I provided a suitable substitute using geophysical cross-correlation (a substitute you allowed in your challenge).

In answer to your questioning the validity of cores due to our lack of knowledge of depths: that is the point of correlation. It is possible to determine sedimentation or ice accumulation rates for specific basins or areas. The process of doing this though is of limited value as it is time consuming and very localised (particularly with ice accumulation). Instead it is suitable to correlate data from one core (ice or sediment) or area with data from another area or core (where the chronostratigraphy is known already) to date the historical horizons one chooses to analyse.

This principle of cross-correlation is one of the bedrocks of the geophysical discipline (ha geology joke yay!) and claims that it is inaccurate would thus call the whole scientific area into question. Believe me this, along with the other principles of stratigraphy and geology, have been tested numerous times and are not just blindly followed.

 

[Captain Wes]

I'll just cast fix environment. It'll cost me some mana but I'll just drink a blue potion. Next!

 

[crimson5pheonix]

Good ideas, except for a couple of things. First, LEDs are still less efficient than fluorescent tube lighting, high wattage metal halide, and almost all high and low pressure sodium lighting, although they are getting scary good in efficiency. We are just starting to use them in commercial designs (other than low wattage things like exit signs) within the last year.

How are they less efficient? Last I checked they use 1/10th the electricity of fluorescent bulb. You can use a voltmeter to check the actual electric pull from several electric sockets.

 

[werepossum]

Good ideas, except for a couple of things. First, LEDs are still less efficient than fluorescent tube lighting, high wattage metal halide, and almost all high and low pressure sodium lighting, although they are getting scary good in efficiency. We are just starting to use them in commercial designs (other than low wattage things like exit signs) within the last year.

How are they less efficient? Last I checked they use 1/10th the electricity of fluorescent bulb. You can use a voltmeter to check the actual electric pull from several electric sockets.

Two 32W T8 835 lamps driven by a 0.88 ballast factor instant start ballast outputs 5,016 lumens for 58 watts, or 86.5 lumens per watt. Four 32W T8 835 lamps driven by a 0.88 ballast factor instant start ballast outputs 10,032 lumens for 112 watts, or 89.6 lumens per watt. 54W T5HO lamps provide about the same efficiency; 28W T5NO lamps provide the highest, about 98 to 101 lumens per watt. A 1,000 watt high pressure sodium lamp provides 112,000 mean lumens at 1,059 watts or about 105.8 lumens/watt.

LEDs are not yet standardized in wattage or output, but typically run 20 to 60 lumens per watt. A typical 5W LED might provide 240 lumens or 100; a 1W LED might provide 60 lumens. Some of the bleeding edge claim 80 lumens per watt, but that doesn't include driver losses and real world tests have yet to determine actual life. Heat is the enemy of LEDs, specifically in killing the drivers. I'm starting to see some claimed 80 lpw LED fixtures which are being offered but not yet shipping, but we've seen LED claims before that didn't measure up.

One of the best fixtures I've seen is LED Lighting Fixtures (now Cree) down light. It claims the same output as a 26W quad tube (not a particularly efficient lamp, figure 1800 lumens at 65% reflector efficiency at 28 watts) for only 12W, but has little control; light goes out almost equally in all directions, which means little directly strikes the floor or desk. They're great for low ceilings, but unusable for higher ceilings. Others like the new Halo LEDs have better controllability, but use 18W for output slightly below that of a 26W quad tube. So LEDs are currently as efficient or more so than compact fluorescents and smaller HID lamps, but less efficient than tube fluorescents and high wattage HID lamps.

You may be thinking incandescents, which range in efficiency from roughly 12 lumens per watt for cheapo A-lamps to 22 lumens per watt for the best halogen infrared reflector PAR lamps. Even so, there are no lamps available today that use ten times the electricity of any commercially available LEDs for the same light output.

For measuring power, use a watt-meter. Some LED drivers still have rotten power factors, although most aren't so bad anymore. And watch out for measuring voltage in sockets if you are around HID lighting; both sodium and the newer metal halides are pulse-start, generating a voltage pulse of 4,000 to 6,000 volts to start the arc. They can kill you. For that matter, a fluorescent instant start ballast can give you a nasty shock as well, which I suppose could be lethal if you were well-grounded.

 

[werepossum]

SNIP
I realise that you initially referred to ice-coring but you then (even in the bold section) broadened your question to geophysical correlation.
I quote:
"Let's say a particular volcano erupted in 1312 and was well documented - where are the projects that accurately predicted the depth of burial for that layer of sediment?"

I provided two such projects for you, one of which has been accurately verified with human records and another which has been verified with an acceptible level of certainty. The Oruanai eruption is very well known in geophysical disciplines and is used as a perfect example of stratigraphic correlation and demonstration of sedimentary layering and dating.

Claiming that these dates or events or correlations are not known as certainties and thus are of dubious value means that you must hold this view for all sciences and as such all research is in vain as it is not able to be objectively proved.

I apologise that I cannot provide data on ice-cores specifically but that is not my discipline, instead I provided a suitable substitute using geophysical cross-correlation (a substitute you allowed in your challenge).

In answer to your questioning the validity of cores due to our lack of knowledge of depths: that is the point of correlation. It is possible to determine sedimentation or ice accumulation rates for specific basins or areas. The process of doing this though is of limited value as it is time consuming and very localised (particularly with ice accumulation). Instead it is suitable to correlate data from one core (ice or sediment) or area with data from another area or core (where the chronostratigraphy is known already) to date the historical horizons one chooses to analyse.

This principle of cross-correlation is one of the bedrocks of the geophysical discipline (ha geology joke yay!) and claims that it is inaccurate would thus call the whole scientific area into question. Believe me this, along with the other principles of stratigraphy and geology, have been tested numerous times and are not just blindly followed.

Sorry, I meant sediments deposited within the ice - although I suppose I shouldn't have used the word "sediments" if I wanted to be understood by a geological student. Mea culpa.

My point was that these are largely unverifiable - even the geological dating in your first example isn't universally accepted, and is not in agreement with the carbon dating by the article. Now push that back past recorded history. We have a great ring of correlation, where method one is correlated by method two which is correlated by method three which is correlated by method four which is correlated by method one. I'm not saying they are necessarily wrong; I'm just saying let's make some nice public predictions and see them verified before we remake the world. So far climate science has proved dandy for explaining things that have already happened; let's see it predict a string of successes.

 

[goodman528]

Stop with all the stats and figures already.

LEDs are more efficient for a very simple reason. LEDs work because of electron-hole recombination, sounds complicated, but all that means is you can control the frequency of light you are generating. Which you can't do with a filament bulb. So, you can see more of the light generated by LEDs then by filaments. Touch a filament bulb, it's hot, touch an LED, it's not hot. This heat is the light you could not see. I think in Halogen bulbs all the Halogen does is make the Tungsten burn differently, so the some logic still applies.

Don't stick volt meters into mains sockets, please, I know it's high resistence and stuff, but you might just kill yourself. It's not worth it.

 

[Dark Crusader]

I personally believe that while humans have helped it along, it's a natural occuring process.
We've probably just speed up the process.

I do care, because it's likely to be in my lifetime, or my childrens life time, that the reprecussions roll around.

 

[clarinetJWD]

No. No. No. No. Hybrids, no. Not only from the viewpoint that they suck all the fun out of driving, but environmentally. Yes they are efficient while in use, but the energy cost of creating the batteries and electronics, etc. that goes into a hybrid, and then into recycling when it outlives its usefulness is astronomical. Your average Jeep is actually friendlier to the environment in the long run, so no. No hybrids.

Uhm... reference to that Life-Cycle Analysis? I don't believe ya.

Sorry, I don't always end up rechecking threads I post in right away...
http://www.katu.com/news/7561002.html

It ranks cars by cost per mile, and offers very compelling evidence. Hummer $2.09, Prius $2.87, and the best 'green car' is the hideous Scion xB at $0.49 (The cost per mile is calculated by "Energy to Society", ot total energy usage over the car's lifetime)

EDIT: Here's the new list for 2008, looks like the xB has fallen from grace, replaced by the (obvious, really) Smart car. It's also excellent that my car (Mustang) is so much less than the Prius.

 

[Jerious1154]

http://www.ipcc.ch/index.htm
this is as close to a definitive voice on this issue as you're going to find. it's the official international panel that was formed to advise policy-makers worldwide on global warming. they dont actually perform studies, they look at all climate change studies that are conducted and compile them into reports on the causes and effects of global warming. most of the site is almost impossible to understand if you're not actually an expert on environmental science, but theres an faq. for those of you who are interested in whether or not it is manmade, look at page 8.
also, please dont fall back on the whole "environmental scare tactics" thing. this is literally, inarguably, the most well respected well researched report that has ever existed on this issue ever.

edit: i tried to put in a link directly to the faq, but it didnt work. just click on faq from this page http://www.ipcc.ch/ipccreports/ar4-wg1.htm

 

[Jark212]

Build giant air filter...

 

[werepossum]

Stop with all the stats and figures already.

LEDs are more efficient for a very simple reason. LEDs work because of electron-hole recombination, sounds complicated, but all that means is you can control the frequency of light you are generating. Which you can't do with a filament bulb. So, you can see more of the light generated by LEDs then by filaments. Touch a filament bulb, it's hot, touch an LED, it's not hot. This heat is the light you could not see. I think in Halogen bulbs all the Halogen does is make the Tungsten burn differently, so the some logic still applies.

Don't stick volt meters into mains sockets, please, I know it's high resistence and stuff, but you might just kill yourself. It's not worth it.

Yes, almost all high-power LEDs are more efficient than filament bulbs - we were discussing the efficiency of LEDs versus fluorescent and arc lamps, and how close we are to LEDs becoming our main source of lighting. You bring up a good point, though; one of the problems with LEDs is the narrow spectrum of radiation. Take low pressure sodium lamps, which also radiate in a very narrow bandwidth. Low pressure sodium is the most efficient light source available, but nobody wants it (unless you're very near a powerful observatory) because of its low CRI (Color Rendering Index.) Sunlight is considered to have a CRI of 100 by default, meaning something in sunlight looks correct to human eyes. That's because all the spectra we can see is present in sunlight. The color green is green because the object emits or reflects light most strongly in the wavelength we call green. Similarly, incandescent or filament light is considered to have a CRI of 100 because things "look right" in incandescent light, even though we know that incandescent light is much more heavily weighted toward the red end of the spectrum compared to sunlight.

Now look at fluorescent light and LEDs. Each technology emits light in a relatively narrow band, the former in UV and the latter in one of a variety of narrow spectra depending upon the material and how it's doped. To approximate white light (light with an even blending of all visible spectra as measured by human eyes), one of a couple things must be done. For fluorescent light, the inside of the tube is coated with different phosphor compounds, either one (for very cheap "warm white" or "cool white" lamps) or three (red, green, and blue for most modern lamps) or even several more (for wide spectrum and high CRI lamps.) Thus the modern fluorescent lamp generally emits in three to six or more narrow spectra to render colors accurately to the human eye. The emitted UV radiation strikes the phosphor coatings, which then glow with visible light.

It can be similar for LEDs. Each LED emits light in a single narrow spectrum - great for a warning light but lousy for general lighting. A bright blue LED can have its plastic enclosure coated with different phosphors which, when struck by the blue radiation, emit several spectra similar to a fluorescent lamp, thus making a white light with good CRI. Another way is to combine specific red, green, and blue LEDs within one fixture or module, so that the three spectra when combined make white light. This is also used with computer-driven drivers to make LEDs that can provide almost any color light by varying the power (and thus emitting intensity) of each of the three individual LEDs. A third way, used by Cree (one of the foremost high-power LED manufacturers in the world), is to combine two LEDs, one red and one blue-green. That gives a pretty good light with less worsening of CRI as it ages.

 

[wgreer25]

Solution: realize global warming is not man made.

Golf claps to you sir for knowing the truth. We can do something about global warming, but we need to realize that it is natural. The idea that we created it is a ruse to either force people to buy certain products or to put money in someone's pocket. Polution is the bigger concern. Here is an article to show how you can't trust all the doomsayers about global warming.

http://www.worldclimatereport.com/index.php/2005/05/27/antarctic-ice-a-global-warming-snow-job/

I can remember Al Gore saying back in the early 90's that if we didn't do something about global warming that very soon coastal citys would start to be under water. People need to start calling out these idiot polliticians when they make these stupid statements.

 

[werepossum]

Solution: realize global warming is not man made.

Golf claps to you sir for knowing the truth. We can do something about global warming, but we need to realize that it is natural. The idea that we created it is a ruse to either force people to buy certain products or to put money in someone's pocket. Polution is the bigger concern. Here is an article to show how you can't trust all the doomsayers about global warming.

http://www.worldclimatereport.com/index.php/2005/05/27/antarctic-ice-a-global-warming-snow-job/

I can remember Al Gore saying back in the early 90's that if we didn't do something about global warming that very soon coastal citys would start to be under water. People need to start calling out these idiot polliticians when they make these stupid statements.

I too believe global warming is mostly natural, and that CO2 inevitably increases as temperatures increase. Animals are always faster to increase activity with increased temperature than are plants, after all. But humans are also responsible for some of the increase in CO2 concentrations. Whether or not CO2 is at or past saturation in global warming, there are still other nasty effects such as acid rain and ocean acidification from increasing CO2 concentrations. Therefore I think we can, and should, find ways to decrease CO2 emissions and to reduce CO2 concentrations.

 

[goodman528]

I only just realised how many people have posted on this topic, without ever thinking about it for a single moment, and just believes whatever Bush, Christianity or the conservative media has told them, and repeats it:

.....etc........
We can do something about global warming, but we need to realize that it is natural. The idea that we created it is a ruse to either force people to buy certain products or to put money in someone's pocket.
......etc......

Solution: realize global warming is not man made.

The ice is not melting faster than all the "experts" said, it did in 2007, but this year we had a 30%, get that, 30% increase over ice at the same time last year. The "experts" were wrong, even they can be full of shit, even they can lie and manipulate to get more funding.

....etc...
Second, the sun is the route cause of everything. So that point is moot, what are you going to do about the sun, huh?
Finally, yes, I agree. A big chunk of the CO2 we are releasing was in the atmosphere in the first place. All we're doing now is just that: releasing it.
...etc...

Am I allowed to say that we can't stop global warming, since it is quite a natural (taken the earth's age and all of that jazz) occurrence? Or will the Global Warming Police arrest me?

The misunderstanding probably happened the first time they were researching the effects of pollution on earth. They probably saw a correlation (Which means a POSSIBLE relation in the changes of values between X & Y) between pollution & the ozone layer/polar ice cap. But if they did, then it was probably seen on statistics that were covering relatively short time-frames.

IT's been said that humans provide only 3% of the CO2 in the atmosphere. (7% is caused naturally by forest fires and other causes...) But switching energy sources is definitely a good idea. I say we go nuclear!

Global warming is nothing more than a heat blip in our earth's history, and like nmmoore13 said, is not man made, no scientific evidence supports global warming....its like saying that man caused all the ice ages as well.

i dont believe in man-made global warimng, but nuclear energy (especially that gotten from heavy water theyre working on) and electric cars are a good way to make russia bankrupt. (lets hope so)

I feel obliged to to say this: First forget absolutely everything you've every heard on this topic. Second, understand this very very simple line of thought:

If you had a box, and you put in more heat then you take out of it, then it heats up. What are we putting into our box? 1 trillion barrels of oil last centry, and 1 trillion more this centry, and even more coal, and some gas also. CO2 heats up under the sun (or more correctly CO2 heats up more compared to N2 and O2). What are we taking out of the box? Only heat transfer by radiation from earth, the same as 5000 years ago.

Here is a pretty picture:

But the effect of CO2 produced by Humans is negligible?

Well, we are digging up and burning about 30% of the world's fossil fuels, if you want to know how much that is, just go to your local coal powerplant, and ask to see physically how much coal they get through in a day, you will be taken to a black mountain. You are putting that sort of a disturbance into the system, then saying the effects are negligible. It's like saying we are producing millions of cars a year, but since we already moved from one place to another before cars existed, so the effect of these cars are negligible.

Any questions?
[please, I'm trying to increase my post count.]


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P.S. I made up the 30% figure, but it's not arbitary, the maximum recovery percentage from an oil well is from 9% to ~60% depending on technology. USA peaked in oil production 40 years ago, most of the middle east will peak in this century. Interesting fact on this: a lot of oil wells produce more water than oil, so really they should be called water wells.

P.P.S. China's energy demand is doubling every few years, look up compound interest to realise what this means, most of that energy is produced by coal. India, Brazil, formal communist block, etc, also growing rapidly, but at a slower rate. You think we are not living in the industrial revolution right now?