Thursday, March 15, 2012

Is there a greenhouse effect?

Skeptics are divided into two camps on the greenhouse effect. The larger camp say it does exist but is of trivial importance for policy and the smaller camp says it does not exist at all.

Being just a humble social scientist with minimal background in physics, it is of no importance for me to take a stand on the question but I have recently been trying to get the issues clear in my head in pursuit of a most unlikely goal: Expressing the theory entirely in plain words so that those of us who are uncomfortable with algebra and technical terms from physics can get a handle on the whole thing.

I think the biggest barrier to understsanding for me has been the old law of the conservation of energy (Yes: I know about Einstein). This law does, I suspect, feel intuitively wrong for almost all of us. It states that energy is neither created nor destroyed. It just bounces around at different times in different places.

Most of us, I think, experience energy as something that gets used up -- as when the gas bottle on our BBQ runs out. But in fact energy is only changed into another form, which may or may not be of any benefit to us.

Lubos Motl, my favourite Pilsener, has been very kind in trying to show me how that works in the atmosphere. This is what I get from it:

When radiation from the sun hits the earth, it warms the earth. But a warm body also gives off heat so the earth warms its atmosphere by convection (contact) but also by radiation. It's not only the sun but also the earth that gives off energy in the form of radiation.

But since the earth is much cooler than the sun it gives off energy in largely different wavelengths. The energy that bounces off the earth is largely in the infrared (IR). But different surfaces respond differently to IR. IR passes right through some gases but gets soaked up by others. Some gases, principally water vapour, soak it up and therefore become hotter. So they become hot bodies too. And what do hot bodies do? They radiate energy in all directions, some of which is downwards toward the earth. And that is the storied Greenhouse effect: The heat that is bounced back towards the earth.

And CO2 is a minor partner in that process. Like water vapour, it too absorbs and subsequently emits IR radiation. Because it is such a tiny fraction of the "greenhouse" process, however, variations in its levels have negligible heating effect on the earth. It's levels of water vapour that matter.

So that's it! That's my attempt to explain greenhouse theory in words only. Partly in response to my desire for a really simple explanation of Greenhouse theory, Roy Spencer has put up his own, much more sophisticated explanation.

And don't blame Lubos for any errors above. Blame my shaky understanding.

And a blast from the super-skeptic camp who think that there is NO greenhouse effect

That skeptics are divided over this matter is a good thing in my opinion. It shows that we are thinking about the science, not just accepting pronouncements from high as nearly all Warmists do. The paper below is headed: "Radiated Energy and the Second Law of Thermodynamics". I reproduce below just the introduction and conclusion but give a link to the whole thing

1. Introduction and terminology

Originally it was thought that the Earth's atmosphere acted like a “blanket” and that trace molecules like carbon dioxide helped to absorb radiation and trap “heat” which would then somehow warm the surface. Carbon dioxide represents about one molecule in over 2,500 other molecules and it (together with about 20 to 50 times as many water vapour molecules and some other trace gases) is, in fact, able to capture “photons” and radiate energy away to space. These gases can even absorb some of the incoming infra-red solar radiation. By reflecting and absorbing some incident solar radiation, the atmosphere does indeed keep the Earth's surface cooler in daylight hours.

Furthermore, there is a long-term close thermal equilibrium between it and the surface, which has been established over some four billion years. Fortunately the crust and mantle beneath it act as very good insulators, retaining thermal energy in the core and only allowing a trickle to leak out. This ensures long-term stability of temperatures, even just a few metres below the surface, and that in turn helps to maintain stability in surface and lower atmosphere temperatures. As a result, the mean of such temperatures (when calculated over 60 years) tends to vary little more than about 2oC above or below the thousand year mean.

But, just as a vacuum flask does not further warm the coffee, neither does any additional temporary thermal energy trapped by the atmosphere warm the surface. Such energy may perhaps “warm up” the atmosphere a little to, say, -35oC or some such temperature well below freezing, but the real insulation property of the atmosphere has more to do with the rate at which warm air rises and creates an inevitable temperature gradient.

So when these original “greenhouse” conjectures (devised by climate scientists) came under the scrutiny of physicists, it became apparent that warm air rises rather than falls, and that any excess trapped “heat” (as they mistakenly called it) would simply be radiated away pretty quickly. So then, in the early 1980's, they had to turn to “Radiative Transfer Theory” and ensure that radiated energy could be seen to dominate the whole process. So they suggested that radiation from the cooler atmosphere would further warm the surface as it made its way up and down, numerous times it seems, dropping off a bit of “heat” on every visit.

But climate scientists have erred in thinking that any “thermal” radiation can add thermal energy to the surface, regardless of the temperature of the surface. This mistaken belief originates from visualising radiation as a flow of mass-less “photons” colliding with molecules in the surface and automatically warming them, if the photons were not reflected beforehand.

There is a need to clarify the fact that “heat” is not automatically transferred wherever “thermal radiation” flows. The very term “thermal radiation” is misleading because it may be interpreted as meaning radiation only in the infra-red spectrum. But these are not the only wavelengths which can bring about a transfer of thermal energy, which may be thought of as a heating process. Solar radiation is nearly half made up of radiation in the infra-red, but the rest in the visible light and ultra-violet spectra can and does transfer even more thermal energy, which warms the surface of the Earth.

8. Conclusion.

Consideration of the effect of the processes involved when the Sun is warming the Earth's surface in the morning leads to the logical conclusion that each such process must stand alone and not violate the Second Law of Thermodynamics. Thus radiation from a cooler atmosphere cannot transfer thermal energy to a warmer surface.

As a corollary, the absorptivity of spontaneous radiation from a cooler source to a warmer target must be zero.

As the assumption of a far greater absorptivity is inherent in the models and explanations of the so-called Atmospheric Greenhouse Effect (in which radiation from the atmosphere is assumed to warm the surface) such models and explanations do not reflect reality.

It is noted that radiation from the atmosphere can reduce the loss of thermal energy by the surface in rare situations related to weather conditions, usually in times of high relative humidity. But water vapour, as well as trace gases like carbon dioxide, can also have cooling effects absorbing some incoming solar infra-red radiation and radiating to space much of the thermal energy in the atmosphere.


Water vapor, not CO2, controls climate and acts as a negative feedback

Physicist Daniel Sweger refutes the catastrophic AGW hypothesis in his paper The Climate Engine, showing that CO2 has a negligible effect upon climate and that water vapor acts as a negative feedback to global warming.

Dr. Sweger uses data from 3 locales to show an inverse relationship between humidity and temperature. He notes, "In the positive feedback mechanism as proposed by the global warming proponents this behavior would be reversed. Then the data would show a positive relationship between moisture content and temperature. But it does not.

The data clearly shows that the relationship between the amount of water vapor in the air and temperature is negative

From the conclusion of The Climate Engine:

The role of water vapor in determining surface temperatures is ultimately a dominant one. During daylight hours it moderates the sun’s energy, at night it acts like a blanket to slow the loss of heat, and carries energy from the warm parts of the earth to the cold. Compared to that, if carbon dioxide has an effect, it must be negligible.

It is also clear from the data presented above that water vapor acts with a negative feedback. The data clearly shows that the relationship between the amount of water vapor in the air and temperature is negative; that is, the higher the amount of water vapor in the atmosphere the lower the surface temperature. In that regard, it almost acts as a thermostat.

As the air cools as a result of an increasing moisture content in the atmosphere, there is a decrease in the amount of water vapor produced by evaporation. Eventually this decrease of the level of water vapor being introduced into the atmosphere results in a decrease in moisture content. At this point more sunlight reaches the earth’s surface resulting in higher temperatures and increasing evaporation.

In the positive feedback mechanism as proposed by the global warming proponents this behavior would be reversed. Then the data would show a positive relationship between moisture content and temperature. But it does not.

As suggested before, data is the language of science, not mathematical models.


Has the far Left deserted Warmism?

There is a poll over at Daily Kos about chief climate fraud Michael Mann. The poll asks readers to evaluate him. This is the result:

Michael Mann:

did not choose to became a symbol
0% 10 votes

has been attacked in many of the same ways that the President and John Kerry were
0% 3 votes

Is an outstanding scientist and human being
0% 8 votes

all of the above
1% 35 votes

is distorting evidence to prove his point
72% 2318 votes

should be fired from the university
25% 806 votes

The result is all the more surprising when we consider that the poll appeared at the foot of an article that praised Mann to the skies. Online polls of course prove nothing but given the known readership of Kos, it has to be a straw in the wind.

A step in the right direction

To the idiocy of recent American energy policy — to the extent we have ever had one — I have devoted considerable attention in these pages. I’ve criticized it under Bush, and even more under Obama, because while Bush’s policy (which was to encourage both fossil fuel and “green energy”) was partly idiotic (the green part), Obama’s (which has been to end fossil fuels and substitute only green energy) has been completely, insanely idiotic.

But the free market, led by entrepreneurs (as opposed to academics, bureaucrats, or other parasites), working primarily on private property (as opposed to public lands, which this administration has locked away), and using private capital (as opposed to taxpayer money), has created a Renaissance of oil and natural gas production.

Even as solar, wind, and biofuel energy has generally proven economically unviable even with massive taxpayer subsidies, the new, unconventional, fossil fuel production — from sources such as shale formations and oil sands deposits, by hydraulic fracturing combined with horizontal drilling — has proven very viable, commercially. It has proven viable, please note, despite a firestorm of new regulations created by the Obama administration, which is eager to choke it off.

That's good news. Here's more.

The symbol of our idiotic energy policy is surely the Chevy Volt, produced by a socialized auto company but poorly received by almost all of society. It has been so poorly received that Government Motors has announced that it is suspending production of the “Sparky Lemon.” Even with massive federal and state subsidies, the whole EV concept has been a flop.

But a recent article in the WSJ reports some good news. A number of car makers are producing cars and trucks that can run on compressed natural gas (CNG), that now inexpensive and clean-burning fuel.

Start with Chrysler. It is announcing plans to build a line of bi-fuel (gas and CNG) powered Ram trucks. And GM is announcing that it will build bi-fuel Chevrolet Silverado and GMC Siena pickups in the fourth quarter of this year.

Honda Motor Company (not being government-run!) is nimbler. It has been selling CNG Civics since 1998 at 200 dealerships spread over 36 states. The starting price for these cars is about $26,600.

Ford, which already for several years has been offering CNG conversion kits for some of its cars, has announced that it will start offering some of its pickups with the option.

CNG-powered vehicles make great sense (as I have argued elsewhere). We can get all the natural gas we need from domestic sources, and it is relatively cheap. Indeed, you can buy conversion kits for any car, and gas compressors for your garage. But it makes most sense if the automakers make the cars powered by CNG right on the factory floor. First, that saves money — pure CNG cars don’t need catalytic converters, for example. And there are economies of scale.

Widespread conversion will take years, because people will move to CNG vehicles only when there is a widespread network of gas stations with CNG pumps. Still, it is a welcome development.

If Obama were sincere when he says, “My administration will take every possible action to develop this energy [natural gas],” he would merit some praise, and I would be happy to supply it. The problem is that in this matter (as in many others), he is lying through his teeth. He has bitterly fought fracking, using every tool in his administration — the Department of the Interior, the SEC, the Department of Energy, and even the Department of Agriculture — while locking away as much public land as he could.

Let’s hope a Republican administration (should we be lucky enough to see it replace the current, benighted one) would truly encourage the transition of vehicles to natural gas, and this country to energy independence. Most of the Republican candidates at least get energy, whatever else they don’t get.



Four current articles below

Typical Greenie arrogance

The "Green" mayor of Sydney wants to get most cars out of the city and says people should cycle instead. But she herself gets around in a chauffeur-driven car -- for trips that could easily be made by bike. She apparently wants to get most cars out of Sydney so her car is not held up by traffic jams

BICYCLE-mad Lord Mayor Clover Moore has been using a council car and driver to take her to parliament - in what appears to be a bending of council rules.

Ms Moore came close to tears yesterday as she said she would be forced to resign from parliament after 24 years because Premier Barry O'Farrell wants to ban councillors from being MPs.

But a classic conflict in Ms Moore's two jobs can be revealed, with Ms Moore's driver regularly taking her - or her bags - to and from parliament on sitting days in a black council Prius.

Yesterday the driver picked her up from a coffee shop, took her to a press conference at the Botanic Gardens and then drove her to parliament.

A spokesman for Ms Moore said she was not breaching council rules and her "daily program while parliament was sitting routinely included appointments related to her duties at the City of Sydney.


Electric cars would stress power grid

ELECTRIC cars plugged into suburban homes would create a risk of causing blackouts by increasing peak demand, the State Government predicts.

The State Government and advocates of the vehicles want owners encouraged to charge the batteries at off-peak times to cause less stress on the system.

Minister for Energy Tom Koutsantonis said the issue needed to be managed like any burden on the electricity grid, such as the uptake of airconditioners.

"Electric cars are a fantastic way to reduce carbon emissions but we need to make sure we manage the way people recharge them," he said.

"We don't want the entire state to plug their cars in at times of peak demand, we want to manage this so that they are plugged in when demand is low."

The Federal Government is currently investigating how an influx of vehicles - predicted to be 20 per cent of all car sales by 2020 and 44 per cent by 2030 - will impact on the electricity grid.

In a written submission to an Australian Energy Market Commission inquiry, the state Department of Manufacturing has warned: "Increased load caused by the charging of electric vehicles could potentially exacerbate peak demand issues currently experienced in South Australia during summer months".

Electric car enthusiast, Adelaide Lord Mayor Steven Yarwood has studied the issue as part of the Adelaide City Council's use of a fully electric Mitsubishi i-Miev car. Mr Yarwood said the cars were similar to the introduction of the internet when people were uncertain how it would operate.

"There are two ways of looking at it and that is in the short term there will be a challenge for the grid and how Governments deal with that but in the long term there is an enormous capacity for the cars to be charged at night time (after people drive home) without any impact on the grid at all," he said.


Carbon tax may cost 1500 jobs in South Australia

TREASURY Department modelling shows the carbon tax will cost the state up to 1500 jobs next year, the State Opposition says.

Liberal leader Isobel Redmond says the estimate is based on modelling the Opposition obtained through freedom of information.

"The impact of this insidious tax on the SA job market will have the effect of negating 75 per cent of the jobs created by the proposed Olympic Dam expansion in the next year," Ms Redmond said.

The Opposition asked a series of questions about the carbon tax in Parliament yesterday.

At one stage Employment Minister Tom Kenyon said he was not aware of any modelling on the impact of the carbon tax on employment.

Soon after, Ms Redmond used details from the Treasury Department modelling to ask Premier Jay Weatherill why he had supported the carbon tax when the Government's own figures showed the tax would cost 1500 jobs once implemented.

Mr Weatherill said the reason Labor supported putting a price on carbon was "because we want a future for our children". "The short-term costs associated with the implementation of a price on carbon will be nothing like the burden of adjustment that will fall upon this state," he said.

Mr Weatherill said what was most damaging for business was the lack of certainty about the future of a price on carbon. "So when a Commonwealth Government accepts its responsibilities and ... does something - which is to put a price on carbon - that is a massive political challenge."

Outside Parliament, Opposition treasury spokesman Iain Evans said it was obvious that the Employment Minister and the Treasurer, Jack Snelling, were not talking to each other.

"Mr Kenyon said he was not aware of any modelling on the carbon tax yet the Opposition has obtained documents from Treasury which show modelling has been done," he said. The carbon tax takes effect on July 1.


Australia should stay open to nuclear says likely new Labor Party leader

FOREIGN Minister Bob Carr says Australia should stay open to nuclear technology, despite Japan's recent nuclear disaster.

Senator Carr, a proponent of nuclear technology, said the push towards nuclear energy was hampered by last year's tsunami and earthquake disaster in Japan, which caused the worst nuclear crisis since Chernobyl.

"I think Japan has set it back because of the impact it's had on insurance and cost," he told ABC Television today.

However, he said Australia should still consider moving towards nuclear energy.

"The fact is, some of the renewables are taking off more slowly than I, as a believer in climate change, would have liked."



For more postings from me, see DISSECTING LEFTISM, TONGUE-TIED, EDUCATION WATCH INTERNATIONAL, POLITICAL CORRECTNESS WATCH, FOOD & HEALTH SKEPTIC, GUN WATCH, AUSTRALIAN POLITICS, IMMIGRATION WATCH INTERNATIONAL and EYE ON BRITAIN. My Home Pages are here or here or here. Email me (John Ray) here. For readers in China or for times when is playing up, there are mirrors of this site here and here


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