Climate Change - Yes or No

General tips, questions and answers about going green in your home and business. Achieve a more environmentally friendly lifestyle!

Re: Climate Change - Yes or No

Postby zzsstt » Sat Feb 05, 2011 2:13 pm

The "bias" is a natural result of the model. The design of a model is such that the known data is used to create a relationship between the various components. There is no other way to create a model. Whether the model is very simple or very complicated, the design is the same. The computer simply does many very fast calculations based solely on what it has been told to do. Any other explanantion of model design is merely gilding the lilly. Equally whether the model compares two datasets or many, the basic structure is the same. To design a model to look at engineering, we take factors like metal density, thermal expansion, loadings etc. We can then produce a model that allows us to simulate the item we are intending to manufacture, and will show us what the structure will do under varying conditions. If we give the model enough data it will tell us wether the materials and design are suitable or will fail, weigh too much or whatever. However this model is based on actual known data - the mass of metal, the specific heat capacity, the stress caused by loading etc. All these components are known and measured, and their interactions are well understood outside of the model.

In the case of the AGW model, however, we have no proof of the relationships. We create a model by saying that (in the most basic form) the temperature has increased at the same time as the levels of CO2 have increased. We then check that model by asking it what the temperature would be when the CO2 level is X (which we told it in the first place) and then use that as proof of the models efficacy. To make matters worse, we then use "increasing variability" as an outcome. Lets be honest, increasing variability incorporates anything and everything!

However, moving away from models for a moment, I had another thought. The theory is that we are creating all this CO2 which is heating the planet. Now it occurred to me that all the fossil fuel being burnt is being used for many things, but eventually all that energy is being turned to heat because heat is almost always the net result of using power. There may be some light created, but when it has stopped bouncing off the walls it becomes heat. When the car has reached the top of the hill (chemical energy to potential energy) and the brakes are used on the way down they slow the car by converting its kinetic energy to heat. So eventually, all that fossil fuel creates heat.

How much heat? According to Wiki we are producing 21.3billion tonnes CO2 per year. According to Wiki the Earths atmosphere weighs 5x10^18kg and air has a specific heat capacity of about 1.01j/g/K. The eficiency of the various uses of fossil fuel varies, but on average it seems to produce about .5kg of CO2 to make 1kWh of power. A kWh is 1000 watts for an hour, and a watt is a joule per second.

I am not going to type the figures, as they are very long!

So, 21.3billion tonnes of CO2 x 1000 (to get to kg) / 0.5 (kg/kWh) gives us the number of kWh produced each year.

5x10^18 x 1000 = mass of the atmosphere in grams

kWh per year (from calculation above) * 1000 (to get to watts) * 60 (minutes) x 60 (seconds) = joules of energy produced per year.

Finally;

joules of energy per year divided by (mass of atmosphere x specific heat capacity) = 0.03degrees

So if we assume that we are indeed converting chemical energy (fossil fuels) to other forms, and that the majority of that energy ends up as heat, then we are creating enough heat to warm the atmosphere by 0.03 degrees PER YEAR. So in 10 years we would warm the atmosphere by 0.03 x 10 = 0.3 degrees.

Al Gore tells us that we have in fact heated the planet by 0.5 degrees in 100 years. Now I haven't done the calculations to total up the heat energy produced in the last 100 years, but if it currently is 0.03 degrees a year I'd guess that 0.5 degrees in 100 years wouldn't be out of the question?

So maybe the CO2 has done nothing, and we've heated the planet directly? If the CO2 has been responsible for the temperature rise, where has the directly produced energy gone? Hmmm, maybe I should design a model!!
zzsstt
Solar Crusader
Solar Crusader
 
Posts: 1296
Joined: Fri Oct 02, 2009 3:27 pm

Re: Climate Change - Yes or No

Postby rg767 » Sun Feb 06, 2011 11:43 am

OK, the world energy consumption, including renewable energy is 474EJ, or 474*10^18 Joules. The energy balance is 174PW.

I started doing calcualtions, but then I found that table below:

Yearly Solar fluxes & Human Energy Consumption
Solar 3,850,000 EJ
Wind 2,250 EJ
Biomass 3,000 EJ
Primary energy use (2005) 487 EJ
Electricity (2005) 56.7 EJ

The addition in heating with respect to energy balance is an incredibly much smaller fraction than what we might imagine, and according to my friend Wikipaedia: "more energy hits the earth every hour than is used in a whole year in primary energy".

And on models: I really don't agree with the way that you represent the climate models: there is nowhere that anyone would say that carbon dioxide concentration equals a reduction in rainfall. That would be biased. It just doesn't work like that.

The variables are many, but never with that direct correlation built in as you suggest.
rg767
Solar Crusader
Solar Crusader
 
Posts: 468
Joined: Sat Jan 02, 2010 8:22 pm

Re: Climate Change - Yes or No

Postby rg767 » Sun Feb 06, 2011 12:07 pm

And so, if you already believe in the greenhouse effect (which you have to, because it is clearly in existence), and given that the amount of energy arriving in the atmosphere is so massive, then a miniscule change in carbon dioxide (a known greenhouse gas) concentration changing the energy balance is not all that hard to imagine.
rg767
Solar Crusader
Solar Crusader
 
Posts: 468
Joined: Sat Jan 02, 2010 8:22 pm

Re: Climate Change - Yes or No

Postby zzsstt » Sun Feb 06, 2011 2:21 pm

rg767 wrote:And so, if you already believe in the greenhouse effect (which you have to, because it is clearly in existence), and given that the amount of energy arriving in the atmosphere is so massive, then a miniscule change in carbon dioxide (a known greenhouse gas) concentration changing the energy balance is not all that hard to imagine.


So your belief is that with a system in equilibrium (not that it ever actually is) between the solar radiation and the greenhouse effect, then a small change to the composition of the gases can make a significant change to the temperature, but a small change to the internal generation of heat cannot?

If we assume that "normally" the temperature of the earth is stable (it never is, as can be seen by the historical temperature data), then the situation is clearly that the solar radiation hiting the earth is fairly much balanced by that which is being radiated back into space. This is a basic requirement, as energy cannot be created or destroyed, so if the energy radiated away is not the same as that arriving from the sun then the temperature of the planet will increase or decrease.

The AGW theory is that the addition of CO2 to the atmosphere has decreased the amount of energy being radiated back in to space, and that additional trapped energy has caused the atmosphere to warm.

It is, however, logical to think that given a constant amount of "insulation" (greenhouse gases) then producing additional heat inside that insulation will increase the temperature until a new equilibrium is created. In your house, if you add insulation but retain the same heating your house will get warmer. However if you keep the same insulation but increase your heating the same will happen - the temperature will increase.

You seem to be suggesting that on a planetary level ths would not happen, but instead the heat created locally would somehow bypass the "insulation".

By the way, the amount of energy received from the sun is not relevant to the concept - we have already established that by simple laws of physics the earth must be radiating as much energy as it receives otherwise it would be in a constant state of heating or cooling.

Why then should it be the case that adding "insulation" will shift the equilibrium, but adding heat (inside the insulation) will not? Clearly there is enough energy to make a difference, based simply on mathematics.

In fact the very concept of the greenhouse effect would surely suggest that locally produced heat is more "dangerous" than solar radiation. If, as is the suggested basis of the greenhouse effect, gas molecules in the atmosphere absorb particular IR wavelengths and then randomly re-radiate the energy, then logically that process would happen in both directions such that solar radiation in those wavelengths would be equally effected. An increasing amount of those gases might well cause some of the incoming energy to be radiated back to space more quickly. Obviously as the wavelengths in question are a very tiny band, incoming radiation will be less impacted, as the theory goes that as the solar energy hits the earth it heats the ground, which then radiates it in the IR wavelengths, some of which wavelengths are the ones we are talking about. Hence, in theory, a greater proportion of the outgoing energy is in "greenhouse" wavelengths than was in the incoming radiation (thus, to put in simply, it comes in and gets trapped). However the overall amount of energy being radiated away from the earth is still the same as that which is arriving, except for alledged AGW impacts. Note then that the heat we are generating from burning the fossil fuels will all be in those same IR wavelengths, and will therefore be impacted by the greenhouse gases and trapped in the atmosphere to exactly the same extent as any incoming solar radiation.

The amount of energy required to heat the atmosphere is the same no matter where it came from. So if the atmosphere has heated by 0.1C it has absorbed X joules of energy to do it. The AGW theory is that this amount has come from trapped solar radiation. However, if our burning of fossil fuels has produced a similar amount of energy, what has happened to it? That energy cannot have simply vanished, it has either passed through the atmosphere and out to space, or has been trapped in the atmosphere and caused it to warm.

rg767 wrote:And on models: I really don't agree with the way that you represent the climate models: there is nowhere that anyone would say that carbon dioxide concentration equals a reduction in rainfall. That would be biased. It just doesn't work like that.


No, like I said, I was simplifying. All models work based on known data. However some models use all known data and all known "rules" and some use the data to extrapolate a rule. How many items of data are included are not relevant to the design, other than to make a bigger and more complex program.

So, for example, an engineering model of a length of steel might include its strength, cross sectional area and weight. From this model we can see how long that length of steel can extend (self supporting) before its own weight creates enough force to bend it. This is a simple model, but based entirely on known data. We can make the model more complicated by adding temperature, and the variation of strength (and length due to thermal expansion) based on temperature. The next step would be to add "design", such that instead of a single piece of heavy steel we could use multiple triangulated pieces of sectional steel, however we are still using known, measured, data.

The other sort of model uses extrapolated relationships. For this model we still use known data, but the relationships are not proven.

If we take our modelling back to the simplist point we end up with a graph. A graph is a graphical representation of data, to model a "relationship". In our engineering model above, we could take length and temperature and create a graph. We could then predict the length of that piece of steel at any given temperature (within the temperature range for which we have experimental proof of the relationship), by reading it from the graph. On the other hand, we could plot a graph (as has laughingly been done in this forum before) of global temperature against number of pirates. We could then plot a best fit line through this graph, but it doesn't prove a relationship. Even the fact that if we look at our historical records and "test" the graph, it means nothing because the grpah was created from those records.

In the case of the AGW model, there is no known relationship between the data items, only a theoretical one. All the "proof" of the relationship is derived from the model. So a model created from the data is used to show a relationship based on the model confirming what it was originally told. Obviously this doesn't mean the model is inherently wrong, simply that it is not "proof".

Your specific point that the model was not told that increasing CO2 means decreasing rainfall is not strictly true. The model is created from data. So it was "told" that in 1900 the CO2 level was X, the temperature was Y, the rainfall was Z...etc. for all the required data items. It was then told that in 1901 the data for those criteria were X1, Y1 etc., and so on for all the years in question. If I entered those same numbers in to Excel and created a graph, I would not have "told" Excel that there was a relationship between rainfall and CO2, but a best fit graph will always find one. The trouble is that as with the "pirates" graph, the fact that a relationship can be found does not prove that one exists! The model uses the data to extrapolate a relationship between the data items, but will do so whether one exists or not. In this case, for the last 100 years the levels of CO2 have been rising. Any data item that exhibits a trend over that period of time will be seen to have a relationship with the level of CO2, whether or not any cause/effect relationship actually exists. So for example, the model has been told that global temperature has been increasing for that time, hence it derives a relationship between the two data items and predicts that if CO2 levels continue to rise, temperature will also rise. In fact that may or may not be true, but the statement that "the model agrees with what has happened" demonstrates only that the model has derived the relationship that it was originally given.

Of course there will be data that does not show any particular relationship, and that even with the full force of statistics brought to bear cannot be shown to have any relationship. This, of course, is where the "increasing variability" comes from. What that means is "we can't find any mathematical relationship between these data items".

rg767 wrote:I started doing calcualtions, but then I found that table below:


That table is of primary energy, it does not relate to the use of energy.

In fact, as described above, none of it is of any importance. Most "renewable" energy is already heat or near enough (wind, solar). Even burning a tree can be considered as part of the very short term energy cycle. Burning fossil fuels however is releasing energy that was stored millions of years ago. The heat released from fossil fuels is energy that is new to the short term energy cycle. It must make it's way through the atmosphere (as heat) before escaping to space. The result is that regardless of the scale of the existing equilibrium, it must have an impact. The size of the impact is based solely on the amount of energy involved. Wiki states "In 2008, total worldwide energy consumption was 474 exajoules (474×10^18
J) with 80 to 90 percent derived from the combustion of fossil fuels." Taking 85% as a fossil fuel use, that means that 85% of 474×10^18joules of heat, or a large proportion thereof, have been produced in addition to the short term cycle.

From my original equations that means we are creating enough energy from fossil fuels to heat the atmosphere by 0.08C each and every year.That energy MUST be heating the atmosphere, as it has nowhere else to go!!!
zzsstt
Solar Crusader
Solar Crusader
 
Posts: 1296
Joined: Fri Oct 02, 2009 3:27 pm

Re: Climate Change - Yes or No

Postby rg767 » Sun Feb 06, 2011 2:37 pm

I don't necessarily disagree with your point that heating causes heating - you are 100% correct, it has to create slightly more heating. Its just the magnitude is far smaller than the other factors.

The other factors end up being a lever of influence over an incredible amount of energy rather than just an additive like local heating.

You also added the amount of heat to the atmosphere also in a previous post to show the amount of heating it could create, and it doesn't work like that as you explained in your last post due to the blackbody effect in the atmosphere. But I get what you mean.

I am glad though that we agree that burning fossil fuels is heating the atmosphere! :)

And primary energy is definately energy? All of the primary energy is expended as heat and gas somewhere during 'conversion'. Even it it weren't, it is still a pretty small factor,and even smaller if you choose to view it in this way.
rg767
Solar Crusader
Solar Crusader
 
Posts: 468
Joined: Sat Jan 02, 2010 8:22 pm

Re: Climate Change - Yes or No

Postby rg767 » Sun Feb 06, 2011 2:41 pm

On models, I think it is simple.

All of the elements have empirically tested properties. Carbon dioxide for example allows for an increased blackbody radiation blanketing effect.

Water vapour has an effect etc. Clouds on albedo - these things are broken down into fundamental cause and effect, but not linked explicitly with each other. Increased carbon dioxide is too far to decreased rainfall.

Carbon dioxide allows a hotter atmosphere, a hotter atmosphere allows for a hotter water temperature, etc, etc...

Its empirical, and models aren't told of a set of conditions anywhere at any time.
rg767
Solar Crusader
Solar Crusader
 
Posts: 468
Joined: Sat Jan 02, 2010 8:22 pm

Re: Climate Change - Yes or No

Postby rg767 » Sun Feb 06, 2011 2:44 pm

rg767 wrote:I don't necessarily disagree with your point that heating causes heating - you are 100% correct, it has to create slightly more heating. Its just the magnitude is far smaller than the other factors.

The other factors end up being a lever of influence over an incredible amount of energy rather than just an additive like local heating.

You also added the amount of heat to the atmosphere also in a previous post to show the amount of heating it could create, and it doesn't work like that as you explained in your last post due to the blackbody effect in the atmosphere. But I get what you mean.



In a nutshell: adding heat is additive, adding carbon dioxide is a multiplier.
rg767
Solar Crusader
Solar Crusader
 
Posts: 468
Joined: Sat Jan 02, 2010 8:22 pm

Re: Climate Change - Yes or No

Postby zzsstt » Sun Feb 06, 2011 6:52 pm

rg767 wrote:I don't necessarily disagree with your point that heating causes heating - you are 100% correct, it has to create slightly more heating. Its just the magnitude is far smaller than the other factors.


The magnitude is not smaller than other factors. The other factors are all in equilibirum, so whilst the numbers may apparently be smaller the net imbalance is still the same. If the atmospheric temperature has changed by 0.5C over 100 years, it is easy to calculate how much energy that involved. I have just demonstrated that the energy from burning fossil fuels is sufficient to cause that 0.5C rise in 6.25 years. Energy is energy, it doesn't matter were it came from!

rg767 wrote:You also added the amount of heat to the atmosphere also in a previous post to show the amount of heating it could create, and it doesn't work like that as you explained in your last post due to the blackbody effect in the atmosphere. But I get what you mean.


The black body concept is a theoretical construct where the energy coming in is equal to the energy going out, and is radiated equally across all wavelengths. From an energy viewpoint, if the temperature is stable then the energy going in MUST be equal to the energy going out, as any difference would cause a change in temperature. The blackbody concept does not impact on what we are discussing.

Primary energy is not heat. Primary energy could be viewed like potential energy - a piece of coal is included as "primary energy" but in fact is just a lump of "rock". It is only when that coal is burnt that it is converted to secondary ("usable") energy. So the earths coal/oil/gas reserves are primary energy, but are not currently taking part in any energy exchange or heating effects.The solar energy reaching the earth is primary energy, as is the kinetic energy tied up in the earths winds. However the question is which of these energy sources are involved in any "global warming" discussion. Overall the earth is more or less balanced between energy received and energy radiated back to space, if we assume for the moment that the atmosphere is actually warming, that increase in temperature may be due to either an imbalance of received/radiated energy, or it could be due to the conversion of local chemical energy to heat. The interesting point is that the amount of heat created from our annual burning of fossil fuel (energy that has been trapped as chemical energy for millions of years) is sufficient to cause the atmosphere to warm at a faster rate than it is actually doing.

rg767 wrote:All of the primary energy is expended as heat and gas somewhere during 'conversion'. Even it it weren't, it is still a pretty small factor,and even smaller if you choose to view it in this way.


No, as above the primary energy is not always heat. The coal that is not burned is still primary energy, but not involved (at present!). Also as above, the "pretty small factor" is more than enough to explain the supposed warming.

rg767 wrote:All of the elements have empirically tested properties. Carbon dioxide for example allows for an increased blackbody radiation blanketing effect.


In a laboratory at high concentrations this has been demonstrated. But at 350ppm? If you have access to any research that experimentally proves this at atmospheric concentrations I would be interested to read it.

rg767 wrote:Water vapour has an effect etc. Clouds on albedo - these things are broken down into fundamental cause and effect, but not linked explicitly with each other.


Cause and effect ARE explicitly linked together. If we tell the model that there is a cause and effect relationship, then the model will reflect that.

rg767 wrote:In a nutshell: adding heat is additive, adding carbon dioxide is a multiplier.


So why if we add enough energy to warm the planet by 0.08C per year (0.5C in 6.25 years) do you believe that the measured increase in temperature is actuall less than that. Surely if CO2 was a multiplier we would be seeing a combined effect of far beyond that rate? Going back to what I said earlier, if you add heat to your house at the same time as reducing the loss, it will get hotter quicker. But in fact the temperature increase would appear to be less than that which must result (by straightforward calculation) from the localy released heat.

If you disagree, then consider the most basic point. If we are releasing enough direct heat to cause the atmopshere to warm more than it is doing (a seemingly easy calculation), then that heat energy MUST be going somewhere. If the increased amount of CO2 in the atmosphere is causing heat to be retained, then where is that energy going?

Also note that, as I have said, the total amounts of energy involved are not relevant. It is only the delta value that is important, and only the delta in heat.

Example: everything you own has a capital value ("primary energy") but for the sake of argument lets say that value does not change. Your bank account has a sum of money in it. However neither of these impact on whether you are becoming richer or poorer. If you get paid $1 a month and you spend $1 a month, you become neither richer nor poorer. If you get paid $1million a month and spend $1million a month, you get neither richer nor poorer. The only important value is the difference between your incomings and outgoings.

The same applies to the earth. If the temperature is constant then it's energy incomings and outgoings are equal. Primary energy in the form of unburnt coal does not change that. However turning that coal into heat does have an impact, and one that is easily calculated as we have done above. Adding that measured amount of heat energy to the atmopshere will warm it. We have calculated that this is more heating than has been measured. If AGW were real, and additional incoming heat was being trapped, surely we would see more temperature rise than that explained by direct energy from burning coal?
zzsstt
Solar Crusader
Solar Crusader
 
Posts: 1296
Joined: Fri Oct 02, 2009 3:27 pm

Re: Climate Change - Yes or No

Postby rg767 » Sun Feb 06, 2011 7:09 pm

uhhh.. no. Adding heat to the atmosphere creates a bit more heat in the atmosphere, but a not proportional increase in temperatures. It looks like you are now saying that the heating of the atmosphere is created by burning fossil fuels, an irony that has not escaped me, but leaves me feeling bemused given the context.

..as above the primary energy is not always heat. The coal that is not burned is still primary energy, but not involved (at present!). Also as above, the "pretty small factor" is more than enough to explain the supposed warming.


No, primary energy is not heat, but it certainly will be converted to it proportional to the energy released. That's why it's measured in Joules.

The interesting point is that the amount of heat created from our annual burning of fossil fuel (energy that has been trapped as chemical energy for millions of years) is sufficient to cause the atmosphere to warm at a faster rate than it is actually doing.


No it isn't - the figures show that it is a tiny proportion of the inconing energy to the atmosphere. As you mention, there is a balance between incoming and outgoing energy.

And 350ppm. Yes, there is plenty of empirical evidence that it creates a heating effect. It not only has a immediate lifetime effect, but an effect running out for tens of years. Some other gases have an effect that runs on for thousands of years. So no, 350ppm doesn't bother me.

So why if we add enough energy to warm the planet by 0.08C per year (0.5C in 6.25 years) do you believe that the measured increase in temperature is actuall less than that. Surely if CO2 was a multiplier we would be seeing a combined effect of far beyond that rate? Going back to what I said earlier, if you add heat to your house at the same time as reducing the loss, it will get hotter quicker. But in fact the temperature increase would appear to be less than that which must result (by straightforward calculation) from the localy released heat.


...If AGW were real, and additional incoming heat was being trapped, surely we would see more temperature rise than that explained by direct energy from burning coal?


It is not a straight forward calculation because you have not included water in the temperature rise, only the atmosphere. Nor have you factored ice melt energy requirements.

The reason we have not seen much bigger increases in atmospheric temperatures is because the atmosphere is not the only thing heating, thats why the calculation doesn't work.

Thats why anthropogenic global warming, or climate change is so insidious.
rg767
Solar Crusader
Solar Crusader
 
Posts: 468
Joined: Sat Jan 02, 2010 8:22 pm

Re: Climate Change - Yes or No

Postby zzsstt » Sun Feb 06, 2011 9:38 pm

rg767 wrote:uhhh.. no. Adding heat to the atmosphere creates a bit more heat in the atmosphere, but a not proportional increase in temperatures.


We have used the specific heat capacity of air to calculate the temperature rise created by that amount of energy. It is a simple concept. Specific heat capacity is the amount of energy, in joules, required to increase the temperature of 1g of the material in question by 1 degree Kevin (or C). If we supply X number of joules to "air" with a specific heat capacity of 1.01joules per gram per degree K, we increase the temperature by X divided by (1.01 X mass of air in grams). We are not talking "proportional", or "a bit more heat", we are talking about a direct calculation.

rg767 wrote:It looks like you are now saying that the heating of the atmosphere is created by burning fossil fuels, an irony that has not escaped me, but leaves me feeling bemused given the context.


I am saying that we are currently stuck on the concept that CO2 is responsible for "global warming" when in fact there is at least one far more likely and easy to calculate cause. That being the case, why are we stuck on the AGW concept? You will also note that the IPCC AR4 actually states that AG gases are "very likely" to have contributed "most" of the temperature increase. "Most" is defined as more than 50%. So even they have not the confidence to state categorically that it "is" responsible, and only attribute potentially as little a half the warming to it! The rest is attributed to land use, solar radiation etc (see another point below).

rg767 wrote:No, primary energy is not heat, but it certainly will be converted to it proportional to the energy released. That's why it's measured in Joules.


Yes, but it's not relevant. A lump of coal is primary energy, but so what? It might stay as primary energy (buried coal) for the rest of eternity. That being the case it has no bearing on global warming, solar radiation or the price of cheese. By the way, the heat produced is not "proportional" to the primary energy contained in the rock, it IS the primary energy in the rock. It is measured in joules because thats the only current unit of energy (calories etc. are old hat!). So a piece of coal when burnt releases 5 joules of energy. If it is in the ground it is "valued" at 5J of primary energy. But in the ground it is neither heating nor cooling anything (releasing or absorbing energy in any form) and therefore has no impact on the discussion.

rg767 wrote:No it isn't - the figures show that it is a tiny proportion of the inconing energy to the atmosphere. As you mention, there is a balance between incoming and outgoing energy.


You seem to not grasp the concept here, but I'm not sure how to explain it any better.

If incoming = outgoing, then any addition to one side of the equation has an impact. If both incoming and outgoing are huuuuge, then a small addition to either side will still cause an imbalance. The imbalance is the only thing that is important, and the impact of that imbalance is the same no matter how large or small the incoming and outgoing.

For example;

+1 - 1 = 0 = no change
+1000000 - 100000 = 0 = no change

+2 -1 = 1 = an increase of 1
+1000001 - 1000000 = 1 = an increase of 1

The size of the equilibrium is not important, it is the size of the change that matters. We know the size of the change (or at least Wiki thinks we do!), and we can easily calculate the effect that change will have.

rg767 wrote:And 350ppm. Yes, there is plenty of empirical evidence that it creates a heating effect. It not only has a immediate lifetime effect, but an effect running out for tens of years. Some other gases have an effect that runs on for thousands of years. So no, 350ppm doesn't bother me.


I asked for experimental evidence. You have simply stated that "it does". You have also stated that other gases have effects for thousands of years, a statement that will be even harder to back up with experimental evidence because it is totally theoretical. However, I'll ask again. Please point me to some experimental evidence that 350ppm CO2 has an effect in the atmosphere. I am genuinely interested because I have only seen "high concentration" data of actual effects, with the "low concentration, real world" theories extrapolated from them.

rg767 wrote:It is not a straight forward calculation because you have not included water in the temperature rise, only the atmosphere. Nor have you factored ice melt energy requirements.

The reason we have not seen much bigger increases in atmospheric temperatures is because the atmosphere is not the only thing heating, thats why the calculation doesn't work.


You are correct, I haven't included ice melt energy, nor water temperature rise. I have only included air. But equally I have not included other sources of local heat such as energy released from an extra 6 billion humans metabolising vegetation that would otherwise have stored incoming solar energy for decades or millenia. Burning timber that has been soaking up energy for many decades and has now been released in a few years. I haven't included a great many sources and sinks of energy. A tree absorbs solar energy and converts it to primary (chemical) energy. If that tree is cut down and burnt, all the stored energy is released as heat. If instead of a new tree, the area is now covered with concrete (or simply bare dirt), then not only has the energy stored there over many years been released, but the ongoing conversion of solar energy to chemical energy is halted. The result? A sudden release of heat (burning the tree) followed by a reduction in the amount of energy converted from light to chemical energy. That light is now converted directly to heat.

So for every square meter of ground that is not growing a plant, nearly 100% of the solar energy is converted to heat. Now consider how much land area has been cleared of vegetation (not to be replanted with other vegetation). All the energy in that vegetation has been released as heat (OK, so some trees have been made in to houses or tables, but you get the point) and all the energy arriving there is now creating heat, rather than new plants. Even farmland that is "fallow" between crops has the same effect.

So if we take a large city, and calculate the difference between converting that area of sunlight to heat and converting it to trees, how much extra heat would we find? Multiply that up by every square kilometer of the earths surface where we have removed the solar to plant matter conversion and replaced it with solar to heat.

The direct heating from burning fossil fuel was simply one example of an alternative to AGW, as is the conversion of woodland to concrete. I am sure I could think of many more if I bothered. However the most important point is that we are stuck in the single minded concept that CO2 is responsible for global warming (as mentioned above, even the IPCC actually state "most" - more than 50%, is "very likely" caused by AG gases, leaving a great deal of wriggling room!). In fact CO2 may well be a part of it. So might direct heating from coal. So might replacing trees with concrete. So might solar activity. On the other hand it might be that at some point in the future the temperatures start to fall because this was simply a small rise in a cycle, chaotic or otherwise, that we have no grasp on whatsoever! Science is known for doing backflips on a regular basis, after all.

The important point is that we are abusing the planet in many ways, squandering resources to satisfy our short term greed. But that is our nature, isn't it? At present we are stuck on an "anti CO2" policy, but even that policy is underpinned by finance and profit - the plans to "fix" AGW all revolve around a profit for somebody, and little to do with CO2! We will not reduce our usage of fossil fuels, because fossil fuels are easy and cheap. We may play about, creating a revenue stream from taxing them, but we'll never do enough to threaten our profits and therefore never do enough to make a difference.

It is also interesting that whilst the IPCC state that perhaps only just over half of the warming is caused by CO2, we rarely hear about any other causes even though they may be almost as important. I could suggest why that is the case, especially given the content of the Copenhagen proposal.....
zzsstt
Solar Crusader
Solar Crusader
 
Posts: 1296
Joined: Fri Oct 02, 2009 3:27 pm

PreviousNext

Return to Living Green

Who is online

Users browsing this forum: No registered users and 1 guest

new solar power specials