What is often quoted is that CO2 doubling causes an increase in radiance to earth’s surface of 3.7 watts/meter squared, which in turn raises temperatures about 1 degree Celsius.  Why the reference to “doubling”?  Because we’re talking about light and filtering materials.  Consider that you have several pairs of sun glasses, each of which blocks 50% of the light.  If you put two pairs in a row, do they block 100%?  Of course not.  The first pair blocks 50% and the second pair blocks 50% of what is left, which is 25% of the original light.  The third pair would only block 12.5% of the original light.  CO2 suffers from the same law of diminishing returns.  What keeps getting left out of the climate discussion is what happens after the first doubling.  The pre-industrial levels (1900 AD or so) of CO2 are commonly quoted at 278 PPM (parts per million) and the current levels are at about 385 ppm.  If we look at this graph, it becomes pretty clear that we would have to generate a LOT of CO2 to get much more effect than we are already: 

It takes more and more CO2 to get just one more watt...

However, to keep the big picture in mind, we have to also remember that as the earth gets warmer, it radiates heat to space.  The ideal black body formula to calculate how much heat is being dissipated to space is P=(5.76×10^-8)(T^4) where P is power in watts per square meter and T is temperature in degrees K or Kelvin.  To convert from the more common degrees C, just add 273.  The “average” temperature (there’s really no such thing) of earth is often quoted as 15 degrees C or 288 K.  This graph shows how much additional heat the earth sends into space as it gets just a few degrees warmer: 

The warmer something is, the more heat it radiates...

So how much does CO2 in theory heat the planet?  If we use the formula above, we see that increasing the earth’s temperature by just 1 degree, from 288 K to 289 K, results in an increase in earth radiance of 5.5 watts per square meter.  This brings up the obvious question.  If earth radiance goes up by 5.5 watts, how could it be caused by only a 3.7 watt rise?  The climatologists have a variety of explanations for this.  In brief, CO2 doesn’t reflect long wave radiance as many people think, it absorbs it.  This heats the CO2 up, which causes it to radiate more heat, but the photons it releases can be emitted in any direction.  Up, down, sideways…  long story short, some escapes to space and some gets sent back to earth, about 3.7 of the 5.5 additional watts.  This issue alone is a long complicated discussion, but rather than argue it, let’s just accept the numbers.  Doubling CO2 levels from the pre-industrial level of 278 PPM causes an increase of 3.7 watts per meter squared, and that results in a temperature increase of 1 degree C.  The various theories then go on to claim that increased temperatures result in increased water vapour, which is itself a greenhouse gas and supposedly adds another 2 degrees C to the warming.  We’ll debunk both of those, but let’s put aside the water vapour for the moment and just focus on the CO2.  

In order to put the whole thing in perspective, we have to keep in mind two things.  The first is that in order to get a second 3.7 watts (after the first doubling) we would have to double CO2 again.  So the first doubling would be 278 x 2 = 556 PPM = 3.7 watts.  To get to 7.4 watts, we would have to double again to 1,112 PPM.  As the earth heats up though, the amount of additional power required to raise the temperature just one more degree also goes up.  So, to put everything in perspective, let’s take a look at how much CO2 would be required, without water vapour feedbacks, to directly raise the temperature of the earth from 288 K (15 degrees C) by four degrees.  As you look at the graph, just to put things in perspective, consider the two thin lines at the bottom.  The green line is what CO2 was at pre-industrial, and the red line is where we are at after a century of burning fossil fuels: 

Even at double current rates, it would take over a century to get to +2 degrees....

Several things jump out at us.  The first is just how ridiculous the idea of a “tipping point” really is.  The amount of heat the earth radiates to space just goes up too fast for that, and the amount of CO2 that is required to maintain any temperature increase at all goes up even faster.  If we were to double the rate at which CO2 in the atmosphere is increasing in comparison to the last 30 years, it would still take well over a century to get to just two degrees of warming from CO2.  If we tripled the rate, it would take almost four centuries to get to three degrees.  But what about positive feedback from water vapour? 

There are plenty of things wrong with that theory.  In principle, the amount of water vapour the atmosphere is capable of holding about doubles for every 10 degree rise in temperature.  The theory goes that just a small rise in temperature would increase water vapour which over all has a much larger greenhouse effect than does CO2.  Estimates range anywhere from double to quadruple the additional warming.  The average quoted most often is 1 degree of warming from CO2 and 2 more from water vapour feedback.  Is this reasonable? 

If the amount of water vapour in the atmosphere always “maxed out” it might be, but we know that doesn’t happen.  Instead, let’s look at what has actually happened.  Since the pre-industrial levels of 278 PPM one hundred or so years ago, CO2 levels have gone up about 38%, not even close to doubling.  In that time, various estimates based on surface station readings around the world have suggested that the earth has warmed up about 0.6 degrees C.   But, we must keep in mind that due to the logarithmic effects of CO2 forcing, and the increased radiance of the earth as it warms, the first 38% has a much larger effect than the next 38%.  In fact, if we go back to our graph and look at where we are now, it is easy to see that whatever effects doubling CO2 actually has, almost 70% of that is already happening: 

Current levels are up 38%.... which means almost 70% of the effects of doubling CO2, are already happening.

Even if we accepted the notion that positive feedback from water vapour triples the effects of CO2, we clearly are not seeing that in actual earth temperatures.  If the rough estimates of CO2 doubling = 3.7 watts per square meter = 1 degree plus 2 more from water vapour were correct, we would have seen a temperature increase over the last century of 2.1 degrees, but we’ve only seen 0.6 degrees.  It could be argued that there are natural cooling fluctuations, and the difference between what the earth’s temperature is now, and what it would have been without the extra CO2 would be 2.1 degrees.  That also seems far fetched given that the earth has been in a general warming trend for the last 300 years, and the rate of warming over the last century has been about the same as the previous ones.  

The more logical explanation is twofold.  First, the effects of CO2 and positive feedback from water vapour have been far over estimated.  Secondly, even doubling or tripling the amount of CO2 we put into the atmosphere would not appreciably change the warming effects of the CO2 levels we have currently… and then not by much.  This isn’t me making numbers up, it is just a matter of extending the IPCC claims and putting them in perspective to show that the worst is already behind us, and is over estimated in any event.  Even if the estimates of CO2 warming were correct (which they clearly are not) the fact is the bulk of the damage (if any) has already happened, and the amount of fossil fuels we would have to burn to appreciably change that is completely beyond our production capacity.

http://wattsupwiththat.com/2011/06/02/more-climate-model-fail-soil-carbon-not-handled-well/

While the excerpts on WUWT are reasonably clear, I was dumbfounded by this statement:

At lower latitudes, where both average temperature and variability are expected to increase, the release of soil carbon will probably be higher than that predicted by changes in average temperature.

Well golly gee, they’ve managed to invent some new laws of physics.  Not to mention claiming the exact opposite of not just what physics says is most likely to happen, but the opposite of what the IPCC predicts, and the opposite of what the temperature record shows.

The physics requires that the coldest parts of the planet will warm the most, and the warmest parts of the planet (the low latitudes) will warm the least.  The IPCC agrees, that’s why they speak of “polar amplification” on a regular basis.  They even publish the trend over more than a century to show just that:

IPCC predicts the LEAST warming and variability in the low latitudes - as does the physics

If one takes NASA/GISS data and breaks it down by latitude band, the detail jumps out even more:

NASA/GISS by latitude showing the low latitudes experience the LEAST warming and variability

The low latitudes show the least warming and the least variability.  To put that much effort into a study and then quote the physics, the climate predictions, AND the temperature record completely backwards is…. gobsmacking.  More wronger.  Or something.

Does it even matter?

Every ChickenWarmingLittle scare graph is magnified to the point where the blips and curves in the temperature record that we are arguing about are measured in tenths of degrees, sometimes hundredths, and over decades, sometimes centuries.  With our attention focused through the lens of a microscope on a tiny piece of graph, we’ve forgotten that we live in the real world where changes in temperature are orders of magnitude larger every day, every season, and over every latitude change.  We forget perhaps the most important factor of all, which is that ChickenLittleWarming speaks about averages, forgetting that in climate, temperature in particular, there is little meaning, and almost no value, to the word “average”.

Over at WUWT the Stefan-Boltzman Law is being quoted by both sides to discredit the other in regard to how CO2 acts as a greenhouse gas.  But no one disputes the Stefan-Boltzman Law itself which is remarkably simple, and proven by thousands upon thousands of lab experiments.  Without going into the math, it just says that the hotter something is, the more power (watts per square meter) you need to warm it up one more degree.

So let us take the oft quoted ChickenWarmingLittle figures from the IPCC that say doubling CO2 in the atmosphere will result in an extra 3.7w/m2 going downward toward earth surface, and simply accept them at face value.  But instead of getting all wound about if that is possible or not, let’s just set aside the notion of “average”, let’s put the microscope analysis of tiny fragments of the record away, and just use their claim to put things into the proper perspective.

We’ll simply take the annual average temperature records from Yakutsk with pretty much the highest annual temperature variations over the course of the year on earth (not to mention also the coldest), Vancouver, one of the mildest annual temperature variations on earth, and Khartoum, pretty much one of the hottest locations on earth all year long.  Using the IPCC’s 3.7 w/m2 for doubling of CO2 and the logarithmic nature of that, and Stefan-Boltzman’s Law, we can calculate how much warmer each day through the course of the year would be for a given amount of CO2. 

To make it easy to understand, I used temperature records from a period in the range of 380 ppm, which is 100 ppm more than what the IPCC says is normal, and which took over a century of human activity to cause.  Then let’s plot those annual temperature curves on something realistic, a scale humans actually understand.  Not hundredths of degrees of some artificial construct called an anomaly, which is what the ChickenWarmingLittle hockey stick graphs use, just a regular temperature range that you can buy a $10 thermometer for.  -40C to +40C.

To complete the graph, showing those three cities on an annual basis, will add the ChickenWarmingLittle catastrophic, doomsday, we’re all going to die of spontaneous combustion numbers for increased CO2.  We added 100 ppm over more than a century, let’s add double that, 200 ppm more.  That’s about another 150 years from now provided we can somehow find enough oil to sustain our peak burn rate.  Now converting that into w/m2, using Stefan-Boltzman to calculate the new daily temperatures in each of those cities, and graphing them on the same graph, we should be able to see the enormity of the problem.

A century of emissions added 100 ppm of CO2. So let's add 200 ppm more.

Yup, that’s it.  That’s what the IPCC says is going to happen because of all that CO2

We won’t even be able to resolve the argument by real world observation because the chances that we’re going to burn enough fossil fuel to get to 580 ppm in 150 years is about nil, even if we were trying to do it on purpose.  But I can only wonder..will Ira, and Phil, and George and and all the other’s over at WUWT still be beating each other over the heads with physics text books?  I dunno…let’s go check in on them…

http://wattsupwiththat.com/2011/02/28/visualizing-the-greenhouse-effect-atmospheric-windows/

The conclusions on the other hand are often flawed and sometime horrendously so.  Conclusions however, cannot be evaluated against just CO2 and how it behaves when interacting with long wave radiation.  They must be evaluated against the climate system in its entirety, and we are increasingly seeing evidence that many of the catastrophic claims are alarmism based on a massive over estimation of any number of factors that govern climate as a whole.

Yet the discussion always returns to CO2 and what it does.  The claims being fundamentally correct, but the basic explanations being flawed, there have been many attempts to arrive at an explanation simple enough for almost anyone to grasp, while at the same time being accurate enough to be useful as part of the larger discussion.  Not that easy to do, I and many others have failed and failed often.

Recently, Ira Glickstein came up with a physical analogy and posted it on WUWT where it generated a considerable amount of discussion, both pro and con. 

http://wattsupwiththat.com/2011/02/20/visualizing-the-greenhouse-effect-a-physical-analogy/

I think it is one of the best explanations I’ve ever come across that explains what is happening in the atmosphere at a basic concept level from the perspective of CO2 as a “greenhouse gas”.  But as can be seen from the comments, the model isn’t sufficient for other purposes such as understanding how CO2 behaves in a real atmosphere comprised of many other gasses.  It also generates additional questions.  Once people get the basics in their heads, they ask more in depth questions.  In the thread at WUWT, a commenter named “wayne” asked several questions and then concluded with “so, its not warming, its more like delayed cooling”.

My immediate thought was YES!  Not exactly, but close.  How could I depict the issue that wayne was trying to understand at the most basic level possible while retaining a reasonable level of accuracy?  Something I’d done during a white board discussion came to mind and this is the result.  This is my first crack at it, and feel free to be critical or ask questions, I’m looking for feedback so I understand if the messages I’m trying to encapsulate are coming through properly or not.  Then of course there is the possibility I may be wrong.  Well, to be more accurate, I AM wrong.  Models are by their very nature not reality.  They might be close, but at some level they are wrong.  Good modeling is about coming up with a model that is useful, and to the extent possible, as least wrong as can be.

So the explanation that follows is wrong on many levels.  To demonstrate how CO2 results in a warmer earth, I’ve constructed an atmosphere of sparsely populated CO2 molecules and nothing else.  I’m not trying to depict how CO2 interacts with long wave radiations in the atmosphere, I’m only trying to depict how CO2 would interact with long wave radiation if there were no other factors.  To do that, I’ve depicted it in a manner that is far out of proportion from reality.  For example, I show in the slides a photon being emitted by earth surface (LW radiation) as possibly escaping to space unimpeded.  In theory, that is possible.  In practice, highly unlikely.

The chances of any given photon not being absorbed and re-emitted thousands, perhaps millions or billions of times on the way out to space it nearly zero.  Further, when a photon is absorbed and re-emitted, it can be emitted in any possible direction.  It may zig zag up, down and sideways many times before it reaches space.  But at day’s end, the sideways moving photons cancel each other out, and the upward moving photons slightly exceed the downward moving photons.  The model presented is not to in any way to quantify the end result.  The model is only presented to provide an understanding of what the process is, why it in fact does conform to the laws of thermodynamics, that it does not “invent” new energy as many claim, and how the result is a warmer earth surface (in the absence of any other factor, which is again, not realistic)

To quickly review the theory, the sun emits Short Wave (SW) radiation that for the most part goes right through our atmosphere as if it did not exist.  That is because the molecules that make up our atmosphere cannot absorb such high energy photons.  The SW radiation as a result heats up the earth, which in turn results in the earth radiating energy back up.  But the earth is much cooler than the sun, so it radiates much lower energy photons, and we call these Long Wave (LW) radiation. 

LW photons can in fact be absorbed by CO2 molecules, which increases the energy level of that molecule.  But energy always tries to even itself out.  If the molecule absorbs a photon and as a result is at a higher energy state (warmer) than the other molecules around it, that photon will be gotten rid of.  That could happen by transferring it during a collision with another molecule, or simply emitting it so that it zips off at the speed of light in some random direction.

The model below presumes that a certain amount of energy from SW is entering the system at all times.  The number of photons of SW doesn’t matter for this part of the discussion.  What matters is that the amount of energy they carry is equal to the amount of energy of six LW photons being generated by the earth surface.  The model assumes also that even if the CO2 “atmosphere” and the earth surface change in any way due to the “greenhouse” effects of CO2, that the amount of SW absorbed still won’t change.  Again, not realistic, but the model still serves its purpose in terms of illustrating why CO2 in theory warms the earth.

And that, believe it or not, is what all the fuss is about.  The question asked on WUWT by commenter ”wayne” is a reasonable way to think about it.  As a consequence of additional CO2 in the atmosphere, a new equilibrium is established in which the photons escaping to space still escape, but some number of them may be “delayed” on the way out, either existing for an extra moment in time absorbed in a CO2 molecule, or perhaps recycled back down to earth where the result is a warmer earth surface that generates photons at a higher rate to compensate.

But as for the laws of thermodynamics?  Intact. 

As for actual magnitude and actual behaviour in an actual chaotic atmosphere comprised of many different kinds of molecules and subject to many different kinds of processes?

Sorry.  I have no model for that, and my answer is I really don’t know.  That is similar to a lot of climate scientists mind you.  The difference is that they do have a model, but really don’t know.

Now if you want it in simpler terms that make the point, I proudly present The Researcher and the Diptstick:

Researcher; we removed a whole bunch of variables from our model and can now isolate This and show that it is well correlated with That. Since This always follows That, it is clear that there is a possibility for more research to understand how This is caused by That. Send money.

Dipstick; Cool. Hey, what if they have nothing to do with each other? I mean like what if This and That are both caused by Another Thing? Then they’d be correlated with each other but the cause would be Another Thing. Hey, it could be even more complicated than that. What if Another Thing doesn’t actually exist as a Thing, but as any one of 5 combinations of Stuff, you know, Stuff, like those variables you were talking about, maybe there’s 5 different combinations of Stuff that can each cause This and That.

Researcher; You clearly don’t understand science, so shut up and send the money.

Dipstick; You clearly don’t understand money, so shut up and go find some science to show me.

Researcher; You are just a dipstick.

Dipstick; Yes I am. You can even model me. Start by drawing me with my hands in my pockets firmly clenched around my wallet and billfold.

Researcher; You were a lot easier to deal with a couple of years ago.

Dipstick; Yeah, well that was before I read your emails and found out that you made This up, invented That, hid Another Thing, tricked me into believing some Stuff, presented Other Stuff like it was part of Stuff but wasn’t, and now it turns out you can’t find the data you used to calculate Stuff, but there’s tons of data that you Trashed that adds up to Something Else, not Stuff. That’s when I figured out what a dipstick I’ve been.

Researcher; So no money?

Dipstick; Oh lotsa money. Congressional hearings are very expensive.

For brief review, the commonly quoted figures from the IPCC are that pre-industrial levels of CO2 were about 280 ppm (parts per million).  Their estimate is that doubling of the CO2 concentrations in the atmosphere will raise temperatures directly by about 1 degree and that feedbacks from water vapour will add another 1 to 3.5 degrees.  The consensus estimate between the various scientists is a total of 3 degrees.  Since 1920 (the date most often used as the beginning of the industrial age) CO2 concentrations have risen about 40% and temperatures have in fact increased, but by far less than what the IPCC projections suggested.  Let’s put that aside for now and assume that the IPCC projections are accurate.

The IPCC talks about “forcing” and temperature change in the context of CO2 doubling because they accept that CO2 is logarithmic.  Every doubling of CO2 has half the effect per 100 ppm of CO2 of the one before it.  If we put this on a graph it looks like this:

But that’s just my graph.  What about the IPCC graphs?  They show the same thing, though it is presented in such a fashion that it doesn’t jump out at you right away.  Here’s the graph from http://www.ipcc.ch/publications_and_data/ar4/wg1/en/figure-10-26.html of the IPCC AR4 report.  It’s a bit of an eye chart so here’s the quick explanation.  IPCC created a number of potential unmitigated scenarios.  These are essentially a variety of economic forecasts with predictions for each of them in terms of CO2 emissions provided no formal climate mitigation policies are enacted.  All of the various greenhouse gases in addition to CO2 are estimated (they too are logarithmic).  The graphs at the bottom show their combined “forcing” in watts per meter squared, and the expected results.  The first column is the most likely scenario based on current emissions:

The logarithmic curve is easily visible in each scenario.  But cutting it off at the year 2100 is deceptive.  If we were to extend that curve out, we would see that additional CO2 over about 600 ppm just doesn’t make much difference:

Even with CO2 shooting upwards, temperature change falls off.  Keep in mind that the scales in the three graphs are different.  CO2 is being measured in 100’s of parts per million.   Our last century of fossil fuel consumption only resulted in a 100 ppm increase.  Meanwhile, the watts per 100 ppm of CO2 keep falling.  That scale only goes from 0 to 10.  The temperature increase in degrees per 100 ppm of CO2 falls even faster because the amount of heat any body gives off increases exponentially with temperature, so it takes an increasing number of watts to get any temperature change at all.  That temperature scale is only 0 to 6.  Consider what this all means in terms of the worst case scenario compared directly to the best case scenario:

In the IPCC’s worst case scenario, exponential economic growth and fossil fuel consumption results in nearly 1,000 ppm of CO2 in the atmosphere by the year 2100.  This implies increasing CO2 in the atmosphere six times as much this century as last century, and results in an over all world wide increase in temperature of 4.5 degrees.  By 2100 in this scenario, our daily consumption of oil and equivalent fossil fuels would be on the order of 12 times as much per day as it is now.  In the best case scenario, we would arrive in 2100 with about 550 ppm of CO2, but we still get a full 2 degrees of warming despite adding less than a third of the CO2 (we’re at 380 ppm right now so getting to 550 takes another 170 while getting to 1000 takes 620).

The numbers may seem a bit confusing because they don’t  quite fit with the doubling of C02 standard narrative of a 3 degree increase.  The standard narrative is based on pre-industrial CO2 levels of about 280 ppm and temperature at that time which was 0.5 to 1.0 degrees lower.  The figures in this graphic extrapolate from current CO2 levels of about 380 pp and plot temperature increases versus the 1980 to 2000 mean.  In rough summary, an additional 170 ppm in the atmosphere by 2100 raises temperatures by 2 degrees over where we are already.  An additional 600 ppm adds almost four times as much, but raises the temperature 4.5 degrees, only 2.5 degrees more than that.

What scenario trajectory are we on?  We can see the CO2 concentrations being measured by NASA on line:

http://www.esrl.noaa.gov/gmd/ccgg/trends/co2_data_mlo.html#mlo_full

We’re about on track for the best case scenario based on the last 40 years of data.  Of course we expect that our economy will grow, we expect that 2^nd and 3^rd world countries will also industrialise, and so the rate of increase will likely accelerate, though the worst case scenario seems very unlikely.  The IPCC of course is recommending strong mitigation strategies either way.  Just as they created a number of likely scenarios without mitigation, they created six scenarios with mitigation.  They document these in Figure 5.1 of the AR4 Synthesis report (as well as other instances throughout AR4) as follows:

Unlike the first set of figures, these are calculated against pre-industrial temperatures rather than the 1980 to 2000 mean, making them a bit hard to compare.    For rough comparison, let’s simply subtract 1 degree from each of them to arrive at a number that can easily be compared to current CO2 rates and the more recent 1980 to 2000 temperature range scenarios.  Using scenario I to illustrate, it calls for a temperature increase of between 2.0 and 2.4 degrees over pre-industrial, about 1.0 to 1.4 degrees over 1980 – 2000.

In order to achieve that, the IPCC estimates that we would need to cut our fossil fuel consumption by 50% to 85% by the year 2015, just five years from now.  Keeping in mind that since the 2^nd and 3^rd world countries are starting to industrialize and their consumption will grow accordingly, that means that 1^st world countries would have to cut consumption even more to accommodate them.  Or else subsidize their use of uneconomical alternatives through massive carbon credits.

Such a massive fossil fuel reduction world wide seems unlikely without collapsing the world economy.  Scenario V on the other hand calls for consumption to peak in 50 years or so at 25% to 60% higher than current rates.  That yields a temperature increase of 4.0 to 4.9 degrees over pre-industrial, or 3 to 3.9 degrees above the 1980 to 2000 mean.  Yet scenario VI sees consumption peaking late in the century with consumption up 90% to 140%, double that of scenario V, but only adds another 1.2 degrees to the total.  CO2 is logarithmic and these IPCC estimates reflect that.  The worst case unmitigated scenarios are very little higher than the most of the mitigated scenarios!  Of the mitigated scenarios, only the last three are remotely possible without devastating the global economy, and they only result in a temperature increase 1 to 2 degrees less than the worst case unmitigated scenario.  Can another 2 degrees (or even 3) be that catastrophic? 

Edit May 27 paragraph and graphs added:

Here are the unmitigated best and worst case scenarios compared to the IPCC mitigated scenarios.  The scales are different and the unmitigated curves are calculated against 1980 to 2000 temperatures while the mitigated scenarios are calculated against pre-industrial, so be carefull how you compare them:

In brief, our current trajectory, according to IPCC data since 1940 (see above), gives us 3 degrees of warming over pre-industrial by the year 2100. For mitigation scenario III above, if we cut emissions by 30 % starting this year we will save a whopping 0.2 degrees by 2100.  To demonstrate just how small a number that is, let’s consider not the 0.2 degrees we would save by cutting our economy to shreds, let’s instead consider what the worst case scenario to see what it would actually look like.

End May 27 edit

For starters, we have to understand how the IPCC arrives at its various estimates, and then put them in their proper context.  This is not an effort to discredit the IPCC numbers, it is an acceptance of them at face value.  Despite the fact that I think they are exagerated, I will use them as stated to demonstrate the little value there is in the IPCC proposed course of action.

For starters, the IPCC refers to sensitivity in the range of CO2 doubling resulting in an increase of longwave radiance of 3.7 watts per meter squared ( 3.7 w/m2).  This in turn results in direct warming of the earth, based on theoretical physics called “black body” and based on formulas by Stefan-Boltzmann of 1 degrees C.  A detailed explanation of Stefan Boltzmann can be found at

http://en.wikipedia.org/wiki/Stefan%E2%80%93Boltzmann_law 

Positive feedbacks from water vapour are claimed to increase this number to between 2 and 4.5 degrees, with the median consensus estimate being 3 degrees.  But a Stefan-Boltzman calculation against the mean surface temperature of the earth, 15 degrees C, yields a change of 1 degree in the region of 5.5 watts, not 3.7.  The reason for the discrepancy is that the IPCC calculates sensitivity against the effective black body temperature of the earth, which is different from the surface temperature.  Since the earth is surrounded by an atmosphere which is a lower temperature, this makes sense.  The effective black body temperature of the earth as a whole is more like      -20 C.  Interestingly, that’s about the temperature at 14,000 feet above sea level according to NASA’s AMSU-A satellite:

http://discover.itsc.uah.edu/amsutemps/ 

(you will need Java installed and then click on global atmospheric temperature trend and select channel 5)

So here we have our first Aha! moment.  The three degrees for CO2 doubling is calculated at a much colder temperature than the surface of the earth.  The same amount of additional energy flux (power) that would heat the 14,000 foot layer by 3 degrees only adds about 2 degrees at earth surface.  Of course that’s based on the 14,000 foot layer being an average of -20 C and the surface being about +15.  The problem is that there is nothing average at all about the earth’s surface.  It is much warmer at the equator than at the poles.  Summers are much warmer than winter.  Mid day is (usually) warmer than night time.  If an additional 3 degrees (or 4 or 5) was evenly distributed, that would be a gigantic increase.  But it is not evenly distributed by day, season, or latitude.  To understand the real impact, we need to not only understand the average temperature increase, but how it will be distributed.

We frequently hear words like “polar amplification” and references to the arctic regions heating up several times as fast as the rest of the planet.  These things are true.  The various surface station temperature records reflect this as do the satellite temperature records.  Here is the northern hemisphere temperature record since 1880 according to NASA/GISS and broken down by latitude:

 What we see right away is that northern hemisphere temperatures have increased by about 1 degree since 1880.  But arctic region temperatures are up by 2.5 degrees.  With all the excitement about the increase in arctic temperatures and the potential impact on the polar ice cap, we’ve forgotten that the average temperature increase of just 1 degree for the northern hemisphere is not only lower, but that the temperate zones and equatorial regions must be lower still in order for the average to be one degree.  As we look at the graph we see that this is true.  The increase since 1880 in the equatorial region is only about 0.7 degrees.  So now we arrive at our second Aha! moment.  Not only is the estimated temperature increase for the earth surface lower than that for the earth as a whole, but the warmest parts of the earth will see the least additional warming, and the coldest parts the most.  This is precisely in agreement with APCC AR4  observations in chapter 9 of Working Group 1

 http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch9s9-4-1-2.html:

Both of the graphs present the same result for two different time periods of observation.  Arctic temperatures go up more than the average, temperate zone and equatorial temperatures less.  If we return to the previous discussion of Stefan-Bolzmann, the physics upon which the IPCC sensitivity calculations rest, we see that this is exactly what we would expect.  The following are sample calculations to illustrate the point:

P=5.67*10^-8*T^4 is the Stefan-Bolzmann formula where T is temperature in degrees K.

Arctic average temperature  -20 C => +10 watts => +2.5 degrees

Equatorial average temperature  +25 C => +10 watts =>  +1.6 degrees

We can conclude from this that Stefan-Boltzman explains some, but not all, of the lower temperature increases observed when comparing Arctic to Equatorial.  Just as we expect CO2 doubling to result in a higher temperature increase at 14,000 feet than we do at earth surface, we also expect a higher temperature increase at the poles compared to the equatorial region.  But that is still not the complete story.  Earth’s temperatures also fluctuate by season, and by day.  If we go back to NASA/GISS land data since 1881, they provide northern hemisphere temperatures broken down by season.  They are not, unfortunately, also broken down by latitude, but nonetheless we can see that the same relationship applies.  The cold temperatures increase more than the high temperatures:

Across the range of the graph, winter temperatures increase almost 2 degrees while summer temperatures increase by only one degree.  The average temperature increase is somewhere in between.  But this brings us to yet another Aha! moment.  Since we already know that equatorial regions don’t fluctuate in temperature nearly as much as arctic regions, if we were to break this down by latitude, we would expect that winter temperatures in the arctic would fluctuate by an even wider ratio compared to summer.  We don’t have NASA/GISS data to rely on in that regard, but we do have temperature data from DMI for the arctic 80N area since 1958

http://ocean.dmi.dk/arctic/meant80n.uk.php

This allows us to look at the temperature fluctuations and see what cold years look like compared to warm years.  The graphic below compares two of the warmest years, 2006 and 2007 to two of the coldest years, 1963 and 1964.  It is very easy to see that in the coldest years, most of the change was in the depths of winter, and in the warmer years, that is also where the bulk of the temperature change occurred.  To be fair, at the very top of the graph temperatures almost always converge with the annual mean almost exactly.  This is because the top of the graph is just above 273 K, the melting point of ice.  Once atmospheric temperatures reach that point, most of the additional energy goes into melting ice and there is no temperature increase until there is no ice left to melt.  However, if we exclude the top 10% of the graph to get this issue out of the analysis, it becomes clear that almost all the temperature increases seen in the high arctic have come in the depths of winter where a small increase in energy flux results in a higher temperature increase, in keeping with Stefan-Boltzman.

Yet we are still not done understanding the meaning of temperature change in the context of “average”.  We’ve already seen that the average temperature change means different things at different altitudes, different latitudes and different seasons.  It also means different things from day time to night time.  Depending on where you are, diurnal temperature ranges can vary from small to large.  In the tropics where there is high humidity, the range is small.  In a desert, the range can be very large.  Without going into a tremendous amount of detail, let’s take a quick look at what a given level of forcing means in terms of a daily temperature swing.  Consider a hot day in the north temperate zone with an average temperature of 20 degrees.  The low might be 15 and the high 30 degrees C.  But the peak of 30 lasts only a few hours while the low will be spread out over most of the night time period with some of the morning and evening mixed in.  Considering Stefan-Boltzman once more, the same physics that is reflected in altitude, latitude and seasonal variance, an increase of 10 watts/m2 (requiring over 1000 ppm of CO2 to achieve)  would mean that the low for the evening would go up by 1.8 degrees, but the high during the day would only go up 1.6 degrees. 

To review, Stefan-Boltzmann’s equations and the logarithmic nature of CO2 are confirmed by the major temperature records and by all the evidence and projections supplied in the IPCC AR4 report.  They all lead to the same basic conclusions.  The bulk of all warming from a strictly temperature perspective should happen, and is happening, in the coldest parts of the planet at the coldest times of the year.  Put in that context, we have a very different understanding of what the worst case scenario, a rapid and unmitigated economic expansion of the global economy means, in terms of the IPCC’s estimate of a 4.5 degree temperature rise over current levels.  If we consider that 4.5 degrees is calculated against the mean radiative black body temperature of the earth at 14,000 feet, we must first convert that to the mean surface temperature at 15 degrees.  This translates into a surface temperature increase of 3.2 degrees.  If we further break that up by latitude and season, we get very different numbers.  Let’s consider three scenarios.  A tropical zone with average temperature varying seasonally from +25 to +40, a south temperate zone with seasonal variation from 0 to +30, a north temperate zone with seasonal variation from -20 to plus 25 and an arctic zone from -50 to +10.  Here’s what we get:

If we look at a given zone we see that the tropics experience the least warming and also the least variance.  The warm season goes up 2.7 degrees, the cool season slightly more at 3.  At the other end of the spectrum though, the arctic warm season goes up 3.5 degrees, not much more than the tropics.  But the cold season increases a whopping 10 degrees, from -50 to -40. 

Here is a bar graph showing all the zones and their winter temperature change versus the summer.  Even in a worst case scenario, a massive increase in our fossil fuel consumption, summer temperatures don’t go up by the quoted 4.5 degrees.  They go up less than 3 degrees for most of the planet.  Almost all of the temperature increase results in warmer winters in the most bitterly cold parts of our planet.

So again we have an Aha! moment.  Even at the bizarre level of world economic growth that would be required for us to reach the IPCC worst case scenario, the conclusion we should be coming to is not that the planet will somehow incinerate and kill us all.  The conclusion should be that we will see somewhat warmer tropics and slightly warmer summers across the planet, but much, much milder winters.  The 2.5 degrees of warming seen in the Arctic over the last century has been mostly in the winter, and as a consequence, the polar bear population is thriving.  Surviving the summer is not their problem.  Surviving the winter is.  2.5 degrees of warming has helped them survive the winter, but made little difference to their summers.

If we were to choose a more reasonable growth expectation like a 1% year over year increase in CO2 levels, we would arrive at about 660 ppm by the end of this century which the IPCC suggests would be a temperature increase of about 3 degrees over the 1980 to 2000 mean, which is still a higher number than the most likely scenario from the IPCC of 2 degrees.  Using the ideal black body calculation against a three degree rise from 255 K, we get 11.7 w/m2 and we can do the chart again to see how 660 ppm stacks up:

In this much more realistic scenario, with no mitigation, we arrive at fossil fuel consumption over double our current rates by the end of the century, and put almost three times as much CO2 into the atmosphere as we did in the previous century.  While an additional three degrees still sounds alarming on the surface, the same rules apply.  We would expect only 2 degrees or less in the summer, the bulk of the increases would be experienced mostly as milder winters.  Even the hottest days will be experienced more as warmer evenings than as high mid day temperatures.

We could take this analysis to another level still.  Consider that in northern areas, winters are long.  If you get far enough north, it is pitch black for months at a time.  Winter can be eight months long leaving only four more for spring, summer and fall to split between them.  If the temperature goes up 10 degrees in winter, the average for the year would be met with an even smaller temperature rise in the summer than what was calculated above.  The same holds true for night and day.  Even when sunlight is evenly divided between day and night, the peak temperature is brief, similar to the DMI graphs at the beginning of this article.  As a consequence the heating during the cool part of the day takes up a larger portion of the day, and the average is met with less peak temperature rise.  I like math, but that level of detail I’m not excited about.  If you’ve followed along this far, you get the idea.

The bottom line is that if we review the worst case unmitigated scenario, we only save one to two degrees against any of the scenarios that are remotely practical.  If we then take that two degrees and distribute it by latitude and by season, we find that we will have accomplished almost nothing.  Instead of +40.6 on a very hot day in the tropics, it will be +40.  A nice summer day in the north will be 15.9 instead of 15.  And instead of -36 in the middle of winter it will be -40.  And gasoline will be $22.00 per gallon.

My critics will at this point say I have left some things out and I have.  The temperature model I have presented is not valid if one takes into account snow melt.  In my example of the Arctic with a -50 winter and a +10 summer, this would imply snow melting and much of the additional w/m2 would go into driving a state change (from snow to water) rather than a temperature change when spring arrives.  This is a fair criticism and modifying these formulas to account for that is a whole study unto itself.  The point however, is that the bulk of the temperature change comes in the depths of winter, and a winter at -40 instead of -50 is certainly not catastrophic to our biosphere.  For northern temperate zones, the snow will still melt, it will just melt faster, summer will be a bit nicer and winters will be a lot milder.  Would the ice caps and glaciers melt?  There is no doubt that they would be impacted by any warming at all, but let’s note that the polar ice cap doesn’t melt any faster at -40 than it does at -50.  In addition, the IPCC predicts considerably more precipitation, so the question becomes, does the relatively small temperature increase in the summer melt season (which is very short in the first place) off set the increased snowfall in the winter (which is still long)?  I can only observe that despite large temperature increases of 2.5 degrees over the last century, ice seems within normal bounds at both the arctic and Antarctic, and IPCC predictions of sea level rise have fallen far short of estimates.  You can check Arctic sea ice extent here

http://www.ijis.iarc.uaf.edu/en/home/seaice_extent.htm

and you can see Antarctic sea ice extent here

http://www.iup.uni-bremen.de:8084/amsr/ice_ext_s.png

The other two objections regard rainfall and drought due to changing climate patterns, and increased extreme weather.  I will do my best with the first objection, and I will put the second to rest rather forcefully.

The IPCC AR4 report in fact includes projections for increased rainfall.  Rainfall pretty much has to increase given that the whole notion of 1 degree of CO2 forcing becoming 3 degrees due to positive feedbacks is based on substantial increases in atmospheric moisture.  That does not mean however that some areas won’t get less rain and some more.  The AR4 report takes the trouble to predict both temperature and rainfall by latitude:

As can be seen from the chart, The IPCC AR4 report suggests that precipitation will increase for most of the planet with a few narrow latitude bands seeing a few percentage points less.  How accurate is this?  I’m not the one to ask, but again, let’s look at the worst case scenario.  The areas of reduced rainfall are limited.  The great droughts of the 1930’s were followed by an extended cooling period until the late 1960’s.  The warming since then has surpassed the temperatures of the 1930’s, but the droughts have not returned, so they (or those specific ones in any event) were not driven by warmer temperatures.  True, additional precipitation could also lead to flooding and other problems.  So much of what is in the IPCC AR4 report is factually accurate, but presented to be more dramatic than it is.  I don’t know if that is the case for precipitation forecasts, but I will make this observation.  We are not animals.  We build houses to control the climate within them, we build damns to hold the water where we need it and we irrigate where there isn’t enough.  Animals run away or die when confronted with change.  We are humans and we have a much broader range of choices (almost all of them enabled by fossil fuels).  If precipitation sky rockets I think few countries will wring their hands.  They’ll be too busy building hydro electric damns to capture the cheap power.

I will close with a discussion of extreme weather events.  The IPCC narrative is that a warmer planet implies a larger amount of energy stored in various systems.  If an extra 3.7 w/m2 is being retained on the planet due to CO2 doubling, plus 7.4 w/m2 more from water vapour feedback, it by default must be stored somewhere in the system.  Since there is more energy in the system as a whole, there is more potential for storms, hurricanes, cyclones and so on to occur and draw on all that extra energy, resulting in more frequent and more intense weather events.  Of all the distortions and misrepresentations contained in the various predictions for our climate, this one is perhaps the most troubling.  Yes there is more energy stored in the system, but the manner in which it is stored suggests that extreme weather events will decrease, not increase.

Energy can be stored, but for it to move there must be a difference in potential.  If you have two lakes with water in them, but they are at the same elevation, water will not flow between them.  It doesn’t matter if the lakes are one kilometre across or ten kilometres.  It doesn’t matter if they are connected by a garden hose or an aqueduct.  One lake must be higher than the other for water to flow.  Wind doesn’t blow unless there is a pressure difference between two areas.  Hook two fully charged car batteries in parallel and nothing will happen.  In parallel the positive terminals are connected to each other and the same with the negative terminals.  Since the voltage potentials are the same, nothing happens.  If you connect them in series, positive to negative and then the second positive to the first negative… I am warning you not to do this.  The sparks could well blind you, you could start a fire, and if you actually manage to get a good connection, your jumper cables will melt and weld themselves solid.  When there is a large difference in potential energy, stuff happens.

Weather in the short term and climate in the long term are both driven by the same thing.  There are natural processes that create energy potential differences.  The earth spins, heating up each day and cooling off each night.  This causes convection as hot air rises and pulls cold air in below.  It causes pressure changes which drive wind.  It causes water to evaporate which winds up as rain that fills lakes that flow into rivers.  Every single feature there is that we call weather, is driven by natural processes that create differentials in energy potential which deplete themselves as anything from a breeze to a cyclone to a hurricane.  Our long and short term weather is driven by energy differentials that cause circulation of energy from the high temperature tropics to the poles:

I have just spent the last several pages demonstrating via the IPCC’s own data, theory, and published reports, that the arctic zones will heat up more than the tropics, that winters will heat up more than summers, and that nights will warm up more than days.  I’ve confirmed with the NASA/GISS temperature records that these things are true, and the IPCC has imbedded that very conclusion in many of their graphs and calculations.  In other words, while there may be more energy in the system, the energy potential difference is diminished by warming.  From night to day, from latitude to latitude, and from season to season the theoretical physics and the observed results show that the end result is less temperature differential daily, seasonally and geographicaly.  As those are the very things that drive weather, we must conclude that extreme weather events are less likely, not more. 

May 27 edit

Observation bears this out.  Hurricane frequency and cyclone intensity have been in decline despite warming world temperatures and increasing ocean heat content:

end May 27 edit

Given the opportunity to vote for climate change options, I shall choose the one that provides for fewer extreme weather events, milder winters, more fresh water, bigger crop yields and more arable land farther north and at higher elevations.  On a really hot day I will run an air conditioner, and if need be a diesel generator to run that.  The CO2 is good for the crops.  An extra degree in summer won’t hurt me or the rest of the biosphere in any meaningful way.  40 below on the other hand tends to wear on one as one ages.  Even the polar bears are on side.

Ozone exists as a layer of gas in the earth’s atmosphere.   The layer right underneath it is Oxygen.  Both are made of the same atoms (O) but Oxygen is two of them stuck together (O2) and Ozone is a threesome (O3).  So to illustrate, here’s a picture of earth surrounded by a layer of oxygen which is in turn surrounded by a layer of Ozone.  This is not to scale, it is not in the right proportions, there are many other layers, much mixing of gases in each layer, but this is close enough to explain the issues:

The next thing to understand is what happens when Ultraviolet light (UV) strikes the atmosphere.  There are various wavelengths of UV (most commonly grouped as UV-A, UV-B and UV-C).  Because of the big scare concerning Ozone, most people are aware that Ozone absorbs UV which can be harmful to people, so running out of it sounded awful bad.  But some frequencies of UV destroy Ozone, breaking the molecules apart.  Here’s a little movie that NASA made to show UV rays breaking apart Ozone http://svs.gsfc.nasa.gov/vis/a000000/a000800/a000824/a000824.mpg  As the various O and O2 float around, they will meet up and form Ozone again as the video shows.  What the video doesn’t show is that in the real Ozone layer there are all sorts of other molecules hanging around.  Everything from Hydrogen to Methane to sulfur to yes, CFC’s.  Since Oxygen is highly reactive, a free O or even O2 is more likely to combine with them to create H2O, CO2 and other compounds than to go right back to Ozone.

 Other frequencies of UV pass through the Ozone layer, some getting absorbed and some getting through and hitting Oxygen, which causes Ozone to be formed.  NASA made a movie to show that too http://svs.gsfc.nasa.gov/vis/a000000/a000800/a000823/a000823.mpg 

So what we have is a balanced system where Ozone is constantly being destroyed at the top of the Ozone layer, and constantly being created at the top of the Oxygen layer:

So what if something happens to destroy a lot of Ozone?  Well the Ozone layer would thin, and as a result less UV gets absorbed by the Ozone.  This means the amount of UV that gets through the Ozone layer to the Oxygen layer goes up, and so the rate of Ozone creation increases:

The same is true in reverse if the Ozone layer gets thicker .  Less UV reaches the Oxygen layer and so less Ozone is produced until it shrinks to normal once more:

So what about the Ozone holes over the poles?  They’re supposed to be there.  Consider what happens to sunlight as it goes through the atmosphere in earth’s higher latitudes.  Since it has to pass through the Ozone layer at an angle, a lot more gets absorbed than at lower altitudes.  But when we get to the very top of the planet, we reach a height at which the UV is destroying Ozone, but it never gets low enough to strike Oxygen, so the rate at which Ozone is being created falls off:

 As a consequence, most of the Ozone gets destroyed, leaving a “hole” in the Ozone layer.  Actually its not even a hole, its just an area where there are  O2 and O molecules hanging around that used to be Ozone:

Now its not like there is zero Ozone in that hole, there is some because there are Oxygen atoms left over from Ozone breaking down, and they can in fact form back into Oxygen molecules and then into Ozone if they get the right amount of UV (and don’t react with other things like Hydrogen and Methane).  It would be more accurate to call it a “depression” than an actual hole.  There is still “air” there, just not much Ozone in it.  In the early spring the hole starts to grow as the polar region comes out of darkness and the Sun’s rays can start destroying Ozone.  As summer progresses, the inclination to the sun becomes more direct, and the Sun’s rays start hitting the Oxygen layer, creating Ozone.  The reason that the Ozone hole over the south pole is bigger is because earth’s orbit is elliptical which tends to amplify the destruction cycle in the southern hemisphere and diminish it in the northern hemisphere.

So, do people in far northern communities (or far south in the southern hemisphere) need to panic?  In fact, the hole would have to get very big for that to be a problem.  The UV rays we are exposed to, even at very high latitudes don’t pass through the Ozone hole to get to earth surface:

So is the Ozone hole a complete hoax?  Pollutants like CFC’s could make the holes larger in theory, but the fact is that the holes are natural in the first place, and they fluctuate daily as the earth spins, seasonally as the earth’s inclination to the sun changes, annually as the earth’s orbit takes it closer and farther away from the sun, and from fluctuations in the sun’s output of UV in the first place.

NASA is keeping close tabs on the Ozone hole in the Antarctic.  Here’s a graphic that shows how the ozone hole grows quickly and then recovers again annually:

What is often quoted is that CO2 doubling causes an increase in radiance to earth’s surface of 3.7 watts/meter squared, which in turn raises temperatures about 1 degree Celsius.  Why the reference to “doubling”?  Because we’re talking about light and filtering materials.  Consider that you have several pairs of sun glasses, each of which blocks 50% of the light.  If you put two pairs in a row, do they block 100%?  Of course not.  The first pair blocks 50% and the second pair blocks 50% of what is left, which is 25% of the original light.  The third pair would only block 12.5% of the original light.  CO2 suffers from the same law of diminishing returns.  What keeps getting left out of the climate discussion is what happens after the first doubling.  The pre-industrial levels (1900 AD or so) of CO2 are commonly quoted at 278 PPM (parts per million) and the current levels are at about 385 ppm.  If we look at this graph, it becomes pretty clear that we would have to generate a LOT of CO2 to get much more effect than we are already: 

It takes more and more CO2 to get just one more watt...

However, to keep the big picture in mind, we have to also remember that as the earth gets warmer, it radiates heat to space.  The ideal black body formula to calculate how much heat is being dissipated to space is P=(5.76×10^-8)(T^4) where P is power in watts per square meter and T is temperature in degrees K or Kelvin.  To convert from the more common degrees C, just add 273.  The “average” temperature (there’s really no such thing) of earth is often quoted as 15 degrees C or 288 K.  This graph shows how much additional heat the earth sends into space as it gets just a few degrees warmer: 

The warmer something is, the more heat it radiates...

So how much does CO2 in theory heat the planet?  If we use the formula above, we see that increasing the earth’s temperature by just 1 degree, from 288 K to 289 K, results in an increase in earth radiance of 5.5 watts per square meter.  This brings up the obvious question.  If earth radiance goes up by 5.5 watts, how could it be caused by only a 3.7 watt rise?  The climatologists have a variety of explanations for this.  In brief, CO2 doesn’t reflect long wave radiance as many people think, it absorbs it.  This heats the CO2 up, which causes it to radiate more heat, but the photons it releases can be emitted in any direction.  Up, down, sideways…  long story short, some escapes to space and some gets sent back to earth, about 3.7 of the 5.5 additional watts.  This issue alone is a long complicated discussion, but rather than argue it, let’s just accept the numbers.  Doubling CO2 levels from the pre-industrial level of 278 PPM causes an increase of 3.7 watts per meter squared, and that results in a temperature increase of 1 degree C.  The various theories then go on to claim that increased temperatures result in increased water vapour, which is itself a greenhouse gas and supposedly adds another 2 degrees C to the warming.  We’ll debunk both of those, but let’s put aside the water vapour for the moment and just focus on the CO2.  

In order to put the whole thing in perspective, we have to keep in mind two things.  The first is that in order to get a second 3.7 watts (after the first doubling) we would have to double CO2 again.  So the first doubling would be 278 x 2 = 556 PPM = 3.7 watts.  To get to 7.4 watts, we would have to double again to 1,112 PPM.  As the earth heats up though, the amount of additional power required to raise the temperature just one more degree also goes up.  So, to put everything in perspective, let’s take a look at how much CO2 would be required, without water vapour feedbacks, to directly raise the temperature of the earth from 288 K (15 degrees C) by four degrees.  As you look at the graph, just to put things in perspective, consider the two thin lines at the bottom.  The green line is what CO2 was at pre-industrial, and the red line is where we are at after a century of burning fossil fuels: 

Even at double current rates, it would take over a century to get to +2 degrees....

Several things jump out at us.  The first is just how ridiculous the idea of a “tipping point” really is.  The amount of heat the earth radiates to space just goes up too fast for that, and the amount of CO2 that is required to maintain any temperature increase at all goes up even faster.  If we were to double the rate at which CO2 in the atmosphere is increasing in comparison to the last 30 years, it would still take well over a century to get to just two degrees of warming from CO2.  If we tripled the rate, it would take almost four centuries to get to three degrees.  But what about positive feedback from water vapour? 

There are plenty of things wrong with that theory.  In principle, the amount of water vapour the atmosphere is capable of holding about doubles for every 10 degree rise in temperature.  The theory goes that just a small rise in temperature would increase water vapour which over all has a much larger greenhouse effect than does CO2.  Estimates range anywhere from double to quadruple the additional warming.  The average quoted most often is 1 degree of warming from CO2 and 2 more from water vapour feedback.  Is this reasonable? 

If the amount of water vapour in the atmosphere always “maxed out” it might be, but we know that doesn’t happen.  Instead, let’s look at what has actually happened.  Since the pre-industrial levels of 278 PPM one hundred or so years ago, CO2 levels have gone up about 38%, not even close to doubling.  In that time, various estimates based on surface station readings around the world have suggested that the earth has warmed up about 0.6 degrees C.   But, we must keep in mind that due to the logarithmic effects of CO2 forcing, and the increased radiance of the earth as it warms, the first 38% has a much larger effect than the next 38%.  In fact, if we go back to our graph and look at where we are now, it is easy to see that whatever effects doubling CO2 actually has, almost 70% of that is already happening: 

Current levels are up 38%.... which means almost 70% of the effects of doubling CO2, are already happening.

Even if we accepted the notion that positive feedback from water vapour triples the effects of CO2, we clearly are not seeing that in actual earth temperatures.  If the rough estimates of CO2 doubling = 3.7 watts per square meter = 1 degree plus 2 more from water vapour were correct, we would have seen a temperature increase over the last century of 2.1 degrees, but we’ve only seen 0.6 degrees.  It could be argued that there are natural cooling fluctuations, and the difference between what the earth’s temperature is now, and what it would have been without the extra CO2 would be 2.1 degrees.  That also seems far fetched given that the earth has been in a general warming trend for the last 300 years, and the rate of warming over the last century has been about the same as the previous ones.  

The more logical explanation is twofold.  First, the effects of CO2 and positive feedback from water vapour have been far over estimated.  Secondly, even doubling or tripling the amount of CO2 we put into the atmosphere would not appreciably change the warming effects of the CO2 levels we have currently… and then not by much.  This isn’t me making numbers up, it is just a matter of extending the IPCC claims and putting them in perspective to show that the worst is already behind us, and is over estimated in any event.  Even if the estimates of CO2 warming were correct (which they clearly are not) the fact is the bulk of the damage (if any) has already happened, and the amount of fossil fuels we would have to burn to appreciably change that is completely beyond our production capacity.

No Mr Jones, you CANNOT erase the cards and draw your own numbers on them.

Mr Mann, I’m sorry, but you cannot bring your own cards to the table and just substitute some of them when it suits you.

Mr Briffa I can see you have the ace of spades, that’s very nice. But the rules don’t allow you to decide that the other 51 cards no longer count.

Back to you Mr Jones, where did you put those cards you were trying to erase? What do you mean you LOST them? No! We can’t just go on playing without them!

Mr Hansen, I’m sorry, you lost this hand. No Mr Hansen, a straight does not beat a flush. No Mr Hansen, you did not have four of a kind. Look Mr Hansen, you are not an officer of the law, so you can’t put me in jail because you lost the hand. And PREDICTING that you would have four of a kind is not the SAME as having four of a kind.

Put those chips back Mr Ravetz! Poker is about uncertainty, that doesn’t mean you can take half the chips “just in case”. What? Its “urgent”? Look, if you gotta go pee, then go, but you can’t take half the chips with you just because you MIGHT win the hand!

Who the heck are you now? Mugabe? Am I pronouncing that right? Yes you can enter a team late… no… you have to pay for your own chips you can’t make everyone else give you a few of theirs.

Oh for gosh sakes will the interruptions never end? Who are you now? Really? From the UN? I’m impressed…. what… NO! You can’t just decide who the winner is in advance, that’s not how poker works! Well I don’t CARE how many people studied it or how thick your report is… huh? Look, it doesn’t matter if 13,000 professional poker players reviewed your predictions, it doesn’t change how many chips Mr Jones has left!

JONES! Stop that right now! You can’t erase the numbers on the cards and you can’t change the numbers on the chips EITHER. What? You aren’t changing them you’re adjusting them? NO! You can’t adjust them, and you can’t compare your adjustments to Hansen’s adjustments… wait, you’re saying Hansen made adjustments too… Stop that, BOTH of you!

Sigh. Another late entry, sit down young lady. What was the name? Curry? Here are your chips Ms Curry. Now what team are you on, warmist or skeptic? Uh, no, you can’t play for both, you have to pick one. No you can’t wait until one team wins and then decide. OK warmist it is. Ok, skeptic. Ok, warmist…. Ok warmist it is.

Welcome back Mr Ravetz, you are looking much better now, not so uncertain anymore. Uh, yes, I see you brought your own rule book. Well yes, I can see where rule number 24 says it is urgent for you to win. I can see the white out you wrote on top of too… and that’s your rule book not the house rule book, it doesn’t count.

Mr Jones, you have to show me your cards, you can’t just declare yourself the winner of the hand. No, I am sorry, you have to show ME the cards. What? No, it doesn’t matter if you showed them to Briffa and Mann, I can’t just take their word for it, you have to show them to ME. What do you mean why? Because I am the dealer, THAT’s why. It’s my job to look at the cards to verify them. HEY! stop cutting up those cards! Mr Mann I SAW you slide your own cards onto the table while I was grabbing the scissors from Jones, you can’t DO that…. Briffa! Briffa! why are you throwing all the cards in the garbage? NO! keeping the ace of spades does NOT make it the most powerfull card in the world, I already TOLD you that. And origami is very nice but you shouldn’t fold the cards up like that. Yes I know what you made, you made it look like a hockey stick… NO! that doesn’t mean you won!

I QUIT! This is INSANE! I am taking my dog sled team and going back across the ice to Florida where I came from, you bozos can settle this global warming thing on your own!

Dear GreenPeace,

The true sign of a failed belief system is when its adherents, having failed to persuade the populace by reasoned debate, resort instead to violence. It matters not if we are speaking of the millions who died under Communism’s jackboot while their economy disintegrated, or of those murdered by Fascists determined to establish order through racial superiority, or of the brutal repression of the Dark Ages or of Islamic extremists raising their children to become suicide bombers.

What matters is that we understand that these belief systems failed because they were founded upon a false premise. They failed because force of arms and the death of millions can obligate the populace to conform to the belief system, but no amount of brutality and extermination will make the falsehoods into something they are not. The facts will endure no matter how many people are tortured into false confessions, or how many are executed to silence those who would speak the truth. Burning books does not erase the facts within them, only the record of them.

No one let’s go of a long held belief system easily. But those who firmly believe in themselves and their facts will redouble their efforts to convince others by means of persuasion. Those who instead resort to violence to impose their beliefs on others are, by doing so, admitting that they have no other means by which to persuade. Their arguments and evidence having failed, they turn instead to coercion.

GreenPeace would do well to expunge from their midst those who imply that violence may be justified to win the global warming debate. If the facts and evidence are indeed with you, then redouble your efforts to research, document and persuade. But if you allow to exist amongst you those who would choose a path of violence, then you have abandoned reason and fact. You may wrap yourself in a cloak of morality, but the blood stains upon your hands will still be yours. Perhaps instead you should pause and ask why it is that you have set one toe on the same path followed before you by those who had naught but violence to suppress the falsity of their beliefs, and that this perhaps has more to do with your failure than you had supposed.

Putting a gun to my head is not an argument. It is a descent into madness. It is an attempt to repeat history, the lessons of which you clearly have not learned