Behind the Science A Layman’s Explanation of Why Global Warming Predictions by Climate Models are Wrong
| 30 May 2009
I occasionally hear the complaint that some of what I write is too technical to understand, which I’m sure is true. The climate system is complex, and discussing the scientific issues associated with global warming (aka “climate change”) can get pretty technical pretty fast.
Fortunately, the most serious problem the climate models have (in my view) is one which is easily understood by the public. So, I’m going to make yet another attempt at explaining why the computerized climate models tracked by the U.N.’s Intergovernmental Panel on Climate Change (IPCC) – all 23 of them – predict too much warming for our future. The basic problem has been peer reviewed and published by us, and so cannot be dismissed lightly.
But this time I will use no graphs (!), and I will use only a single number (!!) which I promise will be a small one. 
I will do this in three steps. First, I will use the example of a pot of water on the stove to demonstrate why the temperature of things (like the Earth) rises or falls.
Secondly, I will describe why so many climate model “experts” believe that adding CO2 to the atmosphere will cause the climate system to warm by a large, possibly catastrophic amount.
Finally, I will show how Mother Nature has fooled those climate experts into programming climate models to behave incorrectly.
Some of this material can be found scattered through other web pages of mine, but here I have tried to create a logical progression of the most important concepts, and minimized the technical details. It might be edited over time as questions arise and I find better ways of phrasing things.
The Earth’s Climate System Compared to a Pot of Water on the Stove
Before we discuss the average temperature of the Earth, let’s start with the simple example of a pot of water placed on a stove. Imagine it’s a gas stove, and the flame is set on its lowest setting, so the water will become warm but will not boil. To begin with, the pot does not have a lid.
Obviously, the heat from the flame will warm the water and the pot, but after about 10 minutes the temperature will stop rising. The pot stops warming when it reaches a point of equilibrium where the rate of heat loss by the pot to its cooler surroundings equals the rate of heat gained from the stove. The pot warmed as long as an imbalance in those two flows of energy existed, but once the magnitude of heat loss from the hot pot reached the same magnitude as the heat gain from the stove, the temperature stopped changing.
Now let’s imagine we turn the flame up slightly. This will result in a temporary imbalance once again between the rate of energy gain and energy loss, which will then cause the pot to warm still further. As the pot warms, it loses energy even more rapidly to its surroundings. Finally, a new, higher temperature is reached where the rate of energy loss and energy gain are once again in balance.
But there’s another way to cause the pot to warm other than to add more heat: We can reduce its ability to cool. If next we place a lid on the pot, the pot will warm still more because the rate of heat loss is then reduced below the rate of heat gain from the stove. In this case, loosely speaking, the increased temperature of the pot is not because more heat is added, but because less heat is being allowed to escape.
This example is the same fundamental situation that exists with climate change in general, and global warming theory in particular. A change in the energy flows in or out of the climate system will, in general, cause a temperature change. The average temperature of the climate system (atmosphere, ocean, and land) will remain about the same only as long as the rate of energy gain from sunlight equals the rate of heat loss by infrared radiation to outer space. This is illustrated in the following cartoon:
Again, the average temperature of the Earth (like a pot of water on the stove) will only change when there is an imbalance between the rates of energy gained and energy lost.
Global Warming
What this means is that anything that can change the rates of energy flow — in or out of the climate system — can cause global warming or global cooling. For instance, if the amount of cloud cover reflecting sunlight back to space decreases from, say, a change in weather patterns, then more sunlight will be absorbed by the land and ocean. As a result, there will then be an imbalance between the infrared energy lost and solar energy gained by the Earth. The Earth will warm until the amount of infrared energy loss to space (which goes up with temperature, like the heat loss by the pot went up with temperature) once again equals the amount of energy gained by the sun.
But just as in the case of the pot of water, we can also cause global warming by reducing the rate at which the Earth loses energy. For instance, the so-called greenhouse effect of the atmosphere, due mostly to water vapor, clouds, carbon dioxide and methane, acts like a radiative blanket, warming the lower atmosphere and the surface. In the theory of manmade global warming, increasing carbon dioxide concentrations in the atmosphere (presumably due to burning of fossil fuels) slightly enhances the Earth’s natural greenhouse effect. An energy imbalance results because the rate of cooling of the Earth is then reduced slightly — somewhat like putting the lid on the pot of warm water — and as a result the Earth is expected to warm until equilibrium is once again restored.
Now for a magic number that we will be referring to later, which is how much more energy is lost to outer space as the Earth warms. It can be calculated theoretically that for every 1 deg C the Earth warms, it gives off an average of about 3.3 Watts per square meter more infrared energy to space. Just as you feel more infrared (heat) radiation coming from a hot stove than from a warm stove, the Earth gives off more infrared energy to space the warmer it gets.
Comments
He has shown good correlations between the clouds and solar activity as measured by sunspot numbers. I wonder if there is a secondary solar effect. The uv and xray output of the sun is quite variable even though total energy received by the Earth is almost constant. The upper atmosphere puffs up enough when the sun is active to cause low satellites to come down early due to enhanced drag. Could the upper 5-10 percent of the atmosphere change enough to enhance the climate effect of solar variation? If 5 percent of the total mass of the atmosphere is at a reduced density when puffed up, I would expect it to have an enhanced insulation effect. This is my pet theory and I have been looking for a good reference on the upper atmosphere and radiation
I hope not. In this case the science could take a new direction. My hope rests with possible experimental results from the Hadron collider. The Svensmark, et al (2006) paper was pretty convincing as to the immediacy of the cosmic ray effect on cloud seeding with cosmic radiation (iron nuclei); the response was in seconds. The Hadron collider cooperative experiment,howe ver, will bring in numerous additional international investigators. The Danish cloud chamber experiment should have been enough, but sometimes one needs the credibility of a global research team to eliminate the criticism of bias.
Anyone living in the Great Lakes basin during this sunspot minimum has had a practical sneak preview of the future of climate research.
I think I've never heard so loud
The quiet message in a cloud.
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Government Tax policy rests with the need for Global Warming to be true. To admit they got it wrong means an immediate clamour for reductions in Fuel/Energy taxes. Fat chance. Governments are like rabbits in the headlamps on this one.
The real end will come when some bunch of legal eagles see a class action against the main players on behalf of SUV owners and manufacturers. Witness plenty of "I said it COULD, or MIGHT, and POSSIBILITY OF. I never said that it WOULD"
Anyway, if the science of Global warming was truly settled and beyond question, why are we still funding "research" to the tune of Billions?.
Surely if proven beyond all doubt, it should be case of:
Job done, you are not needed any more, thanks for your efforts. Now join the unemployed queue, the auto workers, power station guys and all the truck drivers that you want fired will be along shortly. Couple of new phrases for your new employment - "Would you like fries with that sir?" or "Sorry Ma'am, We stop serving breakfast 2 hours ago."
reducing its consumption and switching to saver and better alternatives
is a good thing, independent of global warming issues.
Unfortunately, since we scientists seem to have fallen prey to this same misunderstandin g, adverse consequences often result as the widespread dissemination of both fact and fiction proceeds apace. Activists, who are usually incapable of distinguishing between the above factors, are nonetheless adept at utilizing them to their advantage. [How often have we been exposed to the claim that tens of thousands of "scientists" who "agree" with the pronouncements of this or that hypothosis masquerading as fact?] To the extent that we scientists continue ignoring this phenomenon, we contribute to the intensity of public reaction that will surely follow when the general populace finally discovers the emptiness of that old 'golden cow' syndrome.
I look at this as the atmosphere being a sort of a thermal diode that traps a signiificant proportion of energy within our atmosphere. And that's a good thing. Anyone who has been in low humidity place like the US deserts will have experienced large temperature excursions from day to night, in the order of 30 to 35 Centigrade degrees.
What greenhouse gases do, in fact, is to MODERATE daily excursions. Deep space is about at 100 degrees Kelvin. A 300 degree Earth, at night, would stuff an enormous amount of energy into the Void if it were not for that thermal diode effect.
Sure, lets get rid of all our greenhouse gases so we can have 50 or 100 degree overnight changes intemperature. Just think of the violent weather that we could experience across such precipitous temperature gradients every sundown and sunrise!
We sit in a nicely designed equilibriuym point right now, which is driven by the solar influx which is between 5 and 10 thousand times greater than all of man's endevours alone. That doesn't even take into account the ongoing outflow of energy from within the Earth, fueled as it is, by other processes we are just becoming aware of. Changes in solar activity dominate the energy equation, not mankind.
Think abut the hubris of the ant of ' The ant and the 'rubber tree plant''. He thinks he's in charge.
The equilibrium point does change, as we have seen, but there are stabilizing mechanisms in place. There's good news and there's bad news. The good news is that we are not the cause, and it's not as bad as the chicken little people say it is. The bad news is that we can't do anything about it. It's a self correcting system. Buy an air conditioner.
Can I copy and send your reply to the MEDIA? I thought it was an excellent perspective, but what about the mass starvation when crops are stunted by not enough CO2? I guess we could all drink Ethanol, isnt that the letest Kool Aid Flavour? Where are all the out of work researchers going to go? Cancer research is nowhere near as forgiving!
Can Al Gore give up his $100,000 speeches?
Great article. It appears that laws of physics push toard equilibrium.
I just read that adding CO2 to water increases growth and decreases water consumption for plants.
Unfortunately if won't make any difference. Simple fact is that there's too much money involved. The scientists, government and other so called experts are making a packet out of the panic and paranoia of the world populace. Seems a spoon fed, cushioned life makes us unable to cope with a few storms and heat waves! So of course there will be no support from the world especially as the majority are happy making themselves feel better by driving less and recycling a few more bottles. And of course i agree we need a more sustainable way of life and we should be more aware of the damaging effects we have on the environment but it seems like a futile effort to prevent a completely natural sleight increase of the global temperature. Mother Nature will keep her own equilibrium with or without us. Its humans that will suffer any effects, which at this point seems likely to focus on our pockets!
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