CO2 and Climate Change
At the root of all matters concerning 'global warming' and 'climate change' lies the introduction of the concept of man-made carbon dioxide having a decisive role in initiating irreversible atmospheric heating.
The heating of the atmosphere by CO2 was first calculated by Arrhenius in the nineteenth century. The actual heating effect has been a matter of speculation ever since, but since the late 1980s a view that it is of a significant and dangerous nature, has been promoted both by environmental lobby groups and governments. The International Panel on Climate Change –IPCC- was set up in 1988 with a remit to examine the science of climatology, and its application in determining the effects of man-made emissions.
This atmospheric heating, due to enhanced capture of solar radiation, has been subsumed into a general concept that the end product is a potentially, disastrously changing terrestrial climate, initiated and continued by man-made CO2.
However, terrestrial climates have always been changing, as is well known from written historical records, and from millennia of geological records.
The heart of the problem is the veracity of the proposed inter-reactions between infra-red radiation from both Earth and Sun, and the manner in which carbon dioxide enhances the heating effects. Secondly is the problem of distinguishing between the influence of man’s generation of CO2 since the Industrial Revolution, and that of the many and varied natural sources of this gas.
The problem was brought to the fore in the world of politics of by a predominantly ideological “green” body of opinion aided and abetted by business interests.
The policies developed by the European Union have dominated activities in the UK. The European Energy Commission driven by ideology rather than analytical science, became attached to a “Renewable” energy generation scenario. This was actively encouraged by business interests, who correctly divined that an industry to generate “clean” energy in whatever form, and backed by an enthusiastic government, irrespective of political colour, was a copper-bottomed investment.
The Commission made the decision to drive forward a renewable scenario, and simultaneously rejected the development of nuclear energy, in spite of the fact that it was a demonstrably low carbon dioxide emitting means of generating power. The reasoning was largely that nuclear energy was derived from a fuel source which was not “renewable”, but in reality devolved about the ideology and technical ignorance of a large number of individuals, in awe of the “Green” movement.
In the UK the Climate Change Act of 2008, which was passed almost unanimously by Parliament, set total UK carbon dioxide emission targets which were ambitious to the point of impossibility. This was due in part to the Prime Minister of the day, Tony Blair, not understanding the distinction between Electricity Energy, and Total Energy.
The targets set were to reduce greenhouse gas emissions by 80% by 2050. By 2020, the ambition is to reduce 2008 levels of CO2 by 18% (33%o 1990 levels), generate 40% of our electricity from low carbon sources, including 30% electricity from renewable sources. Ambitions requiring truly Stakhanovite effort.
The present situation requires answers to the questions:
1. Is the mechanism of the carbon dioxide/atmospheric warming fully understood?
2. Is the connection between global warming and climate changes fully understood?
The earth is heated by three sources; the sun, and internal residual heat, and heat generation from continuing radioactive decay. It is the first of these that is of concern here.
Infra-red radiation from the sun may reach Earth directly, without reacting with either major atmospheric gas. These principal atmospheric gasses, nitrogen and oxygen are totally transparent to infra-red radiation, it passes through them totally unaffected. The gases which interact with infra-red are, in order of the magnitude of their effect, water vapour, carbon dioxide, oxides of nitrogen, methane and minor gases. The amounts of these gasses in the atmosphere, by volume are of the order
Water vapour 2.5%
Carbon dioxide 0.04%
Nitrogen oxides Greatly variable, measured as parts per million
The gasses which interact with infra-red, re-emit the radiation, in all directions. Thus half of the radiation from any molecule will be directed earthwards, and half into space. This applies to both the radiation from the Sun, and from the Earth.
It is that radiation from Earth, and redirected earthwards, that constitutes the “greenhouse effect”.
It is, however, limited in its possible effect. Radiation is re-emitted in any direction, this is termed an “isotropic” process. In the atmosphere slightly more than half the radiation is directed into space, and slightly less impinges on the Earth.
The “forcing effect”, proposed to explain a materially greater return of the radiation to Earth, requires a greater fraction of the radiation to be returned. This proposal is untenable, and could explain, to some degree, why every climate model proposed by the official bodies has not been able to produce effects known from historical data, since they have included some degree of forcing into them.
A different version of the “forcing effect” is that the additional CO2 from man’s activities increases the atmospheric temperature by some degree, thus increasing the amount of water vapour, and enhancing the water vapour greenhouse effect. This raises the question, “why does not the continuous variability of water vapour in the atmosphere have the same effect”; both positive and negative feedbacks may be expected. Moreover, the relative amounts of CO2 and water vapour would favour the involvement of the water vapour effect. But the global temperature stasis negates the existence of either effect. The original hypothesis, unless more complex, does not thus appear to be valid.
The invalidity of Man’s influence is greatly extended by the determination of the amount of CO2 for which his activities are responsible. In 2001 the IPCC reported the concentration of atmospheric CO2 as just 3% of the total. Updated assessment raises this figure to 3.75%, just 15ppm.
Thus the impact of man-made greenhouse gas is that of 15ppm in 25,000.
The present situation concerning global warming, has caused problems for those asserting the overwhelming heating effect of CO2.
During the years 1998 to the present, 2014, global warming has been at a standstill, based on data from both satellite and terrestrial instruments; and is undisputed by the IPCC, the Met Office etc.. The problem thisproduces is an enormous one, since CO2 levels continued to increase, but the “official” view attempts to nullify it. Radiational heating of the atmosphere is an immediate effect. The subsequent transfer of the heat to the Earth is on a time scale many orders of magnitude longer. A separate parameter is suppressing the heating effects of the total CO2 in the atmosphere, in spite of those levels having steadily risen. Carbon dioxide is irrefutably demoted from its putative premier position as the primary global warming gas.
More evidence of the invalidity of the overarching importance of CO2 in global warming comes from the examination of ice cores from the Antarctic. These cores give information on simultaneous global temperatures and CO2 concentration, going back over 400,000 years. At first glance they would appear to support the thesis that increases in CO2 levels gave rise to terrestrial temperature rises. More detailed examination, however, enabling separate decades to be distinguished, reveal that this is far from the case, and, in fact, that it is variation in global temperatures which give rise to consequent variations in CO2 concentration in the atmosphere. This may be of the order of several hundred years.
There is, it is insisted, a “consensus” among “scientists that amounts to 95%, that man-made CO2 causes global warming. The use of “consensus” is an interesting one. Consensus is not by any means a scientific hypothesis awaiting rigorous test. It is little better than an opinion poll from a selection of "scientists" and pseudo scientists. There are many tens of thousands of professional scientists who are not in agreement with the CO2-global-warming and climate change theories - but they are never granted media attention (an official policy within the BBC since 2006!) A recent poll of scientists in the American Meteorological Society reveals that 48% of these professionals, do not support the hypothesis of man-made climate change. An examination of almost 12,000 peer-reviewed papers in Environmental Research Papers in 2013, just 8.2% endorsed the concept of anthropogenic global warming, hardly a 95% consensus.
The Non-Governmental Panel on Climate Change is a notable organisation speaking for these individuals, and publishing factual data overturning a great many of the lurid and fear inducing allegations of the IPCC and the “Green” organisations.
The present position is, however, that the policies of Her Majesty's Government, independent of political orientation, is to promote the concept of disastrous climate change, unless the large scale combustion of fossil fuels is abandoned. It is noteworthy, perhaps, that none of the Secretaries of State for Energy and Climate Change, have had any formal education in the physical sciences, beyond the school curriculum. Very few Members of Parliament are science graduates. The central Government’s ability to question any hypothesis put before them, is, therefore, extremely limited; the question, thus, seldom arises. Nor is any discernable will to become better informed in these areas of science.
The major effect of CO2 in the atmosphere has thus been accepted by Governments world-wide, not merely in the UK. To this end, a number of means of electricity generation have been proposed, with the general title of RENEWABLE. The principle is that use be made of naturally occurring processes such as air and marine movements, solar radiation and geological heat. These are seen as sources of perpetual energy.
It is, however, essential to note an overarching principle for any policy involving physical processes:
It is axiomatic in the field of technology, that the foundation science of any proposed scheme of work has to be demonstrably true, and that the ensuing engineering has to produce an economically viable process. Nature will not be thwarted by Acts of Parliament!
An absolutely fundamental problem arises immediately; electricity has to produced exactly in response to demand. Only that electricity being used by the consumer, or lost in transmission, is generated at the power station. The balance is exact. Electricity cannot be meaningfully stored, or unaccountably lost. Thus, when a consumer switches on any appliance, the generator must be in a position to “make” that electrical power immediately, instantaneously, at any time.
Only one of the systems for renewable generation is able to fulfil this duty, namely geological heat. All are others are subservient to either natural variation of the environment (weather), or to strict timetables, imposed by planetary motion. This characteristic of instantaneous generation, on demand, is held only by fossil fuel, nuclear generation, and possibly by the use of geological heat. This latter is, however, in development, and the quantitative potential in the UK is not known with any certainty.
Hydro-power is a long enough established system of generation to take its place as a renewable. Its further potential in the UK is limited by known geography.
The principal renewable sources in the UK are wind and solar-voltaic generators.
Comparing the winds across the UK, (data from the Met Office), with the wind speeds required for wind turbines to operate at full capacity, onshore wind turbines can only be expected to generate about 25% of their full, theoretical, potential, a figure which has already been shown to drop over one year to 20%.
We simply do not have winds of the required strength, for the required lengths of time.
This is spite of the assertion that we have “the best wind resource in Europe”. Best, perhaps; but very far from satisfactory.
Apart from this fundamental failing, what are the other weaknesses of wind turbines as electrical generators?
1. The winds over the British Isles are very variable both in strength and occurrence. Over this situation we have absolutely no control, and thus no control over their intermittent electricity generation.
2. The question of intermittency has been consistently down-played by the turbine industry. As the nominal contribution of wind power grows to the point where it is an essential part of the UK power supply, this becomes of prime importance, and an increasingly large percentage must have conventionally generated standby, if cuts are to be avoided.
Almost total loss of wind power is caused by large high pressure weather systems dominating the entire UK, the surrounding seas and often N. Europe. This situation is not uncommon, especially in winter. At these times the output from turbines falls to a small percentage of its nominal value. These conditions can last for days, and can cover the whole of the British Isles, and the surrounding sea areas. No wind –no power.
3. Even under “normal” circumstances, the power from turbines is on a “take it when you can” basis. There is no question of it being on demand (dispatchable). Electricity, per se, cannot be stored economically.
4. In spite of the apparent strength of the wind to human beings on stormy days, wind is a feeble source of energy compared with either fossil fuels or nuclear fission. The efficiency of the blades to extract power from the wind allows little possibility of improvement, and the amount of power which may be extracted from an air stream has theoretical limitations (the Betts Limit).
5. This characteristic necessitates the deployment of very many huge machines over large tracts of land, and which is unavoidably intrusive.
6. This intrusion of this on land usage is of the order of a thousand times greater than that of fossil or nuclear installations, for nominally similar generation.
7. The “Grid” has undergone many changes, but remains the bedrock of our power supplies; stable voltages at a stable frequency, controlled centrally. The rise of wind power has complicated the control process since it feeds power in a chaotic and unpredictable fashion. It is recognised by very many Grid Controllers, experienced electrical engineers, that a limit far short of Governmental ambitions, will put the stability of the Grid under great danger. Blackouts have been initiated by the instability of turbine feed into the Grid in Europe. Many wind farms do not operate in accordance with Grid Codes.
8. Every wind farm has to be connected to the Grid in order to make the power available for general use. The scale of this undertaking is not generally appreciated, but will, and does, involve many hundreds, running into thousands, of miles of new pylons and cabling, which may be of considerable individual size, such as the hotly disputed 220 kilometre Beauly–Denny link. The cost of these undertakings, essential for turbine operation, falls, inevitably, on the consumer.
The Department of Energy and Climate Change has, never-the-less, made the fundamentally political decision that wind power is to be developed, while at the same time pressing ahead with closures coal fired power stations as a consequence of EU legislation. Power-on-demand, (dispatchable), is thus being replaced by intermittent, non-dispatchable power.
The need for this intermittent power to be “backed up” by reserve power plant has not been fully understood by those in political circles. Attempts have been pursued to assess the statistical need for backup, instead of recognising the absolute nature of the case. The tardy recognition of the immediate nature of demand and dispatchability has been met with the establishment of a fleet of 0.5MW and 1.2MW containerised diesel generators, sited in “farms”, and ready for use at almost immediate notice. Advantage has also been taken, of the agreement by a number of companies, to be disconnected from the grid if demand becomes critical. Under these conditions other undertakings in the private sector, with surplus generation capacity, have agreed to supply power to the grid.
The Earth enjoys two major sources energy; solar radiation, and heat from the core of the Earth. These two figures differ markedly. Direct solar radiation, outside the Earth’s atmosphere, on the Equator at midday, its maximum value, is approximately 1,366W/m2, the Solar Constant. The terrestrial heat flow is of the order 0.07W/m2.
The apparently large amount of energy available just outside the atmosphere, is considerably reduced when consideration is made of:
1. The time of day.
Solar generation is, self-evidently, zero during the hours of darkness. During daylight hours, generation rises from zero at dawn, to a maximum at solar midday, thence declining to zero again at nightfall
2. The conditions within the atmosphere.
Effects which block the radiation adsorbed by the device reduces power output. Cloud cover and atmospheric pollution by solid or non-aqueous liquid droplets will also reduce the amount of radiation falling upon the device.
3. The latitude.
The maximum intensity of illumination of the device occurs on the equator. The further away from this line, the less radiation will fall upon it, thereby, thereby reducing its output. The radiation will also be reduced by the necessity for it to pass obliquely through more of the atmosphere.
4. The method of capture of the energy.
The energy may be collected directly as domestic hot water. On an industrial scale, large installations in which arrays of mirrors heat a furnace containing bulk molten salts, produce a continuous source of heat for steam raising and electrical generation. These plants are suitable only for arid tropical or sub-tropical sites, since they demand near vertical solar incidence, and clear skies. These sites are generally remote from the centres of demand.
The principal system used for the harnessing of solar energy is using solar voltaic arrays. Solid state photo-voltaic sheet material is mounted in direct sunlight, when electricity is generated, proportionate to the incident energy. Large arrays, solar farms, are becoming more commonplace, and may generate up to several mega-watts. The land use is considerable, and, in the UK, the overall rate of generation is of the order of 25 watts per square metre.
The use of sea areas may be of three kinds
1. Electricity generation by the capture of wave motion. This system has, in fact, the wind as its origin. The power to be extracted from wave motion depends upon the wave height. Frequency of waves also depends upon local sea conditions, depth, narrowing etc. Wave height depends upon the distance over which the wind has been blowing on the sea surface, the length of time for which it has been blowing, and the wind speed. In all cases, the greater the parameter; the higher the wave. Many devices have been designed over at least forty years. They are massive robust machines (and to date, largely unreliable mechanically), in order to withstand the harshest conditions, but are still far from an economic or reliable technology.
2. Tidal currents in some places, run at considerable speeds. In the Pentland Firth currents may reach 11 miles per hour. Propeller-type turbines, similar to wind turbines, but far smaller (water is much denser than air), may be totally immersed in the tidal stream, anchored to the seabed. Continuously varying power is generated, which falls to zero twice per day as the tides turn. Conditions, again, are necessarily harsh, and again the power produced has to be connected to shore based distribution. These costs are again high.
3. Tides may be harnessed by the use of tidal barrages where the geography is suitable. The concept is to obtain power by erecting a barrage, or dam, across an estuary or inlet. Tidal waters flowing in and out past the barrage, do so through turbines, thus generating electrical power. The system has been used in France on the estuary of the Rance. Again, no system is able to run the turbines continuously. Considerable problems are caused when river systems are interrupted in their flow. The solids material, held in suspension by the turbulence of the water, settles on the river bed as a sedimentary deposit; a deposit which may in time build up to prohibitive levels. (Note, The Aswan dam in Egypt now holds huge amounts of the mud previously deposited in the fields in Lower Egypt, which now need fertiliser, and the dam turbines are in danger, no satisfactory solution has been suggested).
In the UK, that the River Severn be subjected to a barrage scheme, has been suggested, but sedimentation is likely to be a major consideration in so heavily muddied waters. In the original consultation on this project, the problem received no mention.
Although rejected as “non-Renewable”, and therefore unacceptable, nuclear energy is a demand responsive generator of electricity. The amount of CO2 attributable generation is also very low.
The source of energy in nuclear generation, lies in the conversion of a small amount of the mass of the uranium atom into energy, when that atom divides into two roughly equal halves. The quantity of energy released is on a scale totally out of the normal experience. When one atom of carbon is oxidised to carbon dioxide one “unit” of energy is released. This is our normal coal-fired method of raising steam for electrical generators. When one atom of uranium 235 fissions, about 60,000,000 of those same units of energy are released. This is outside normal comprehension, and explains the tiny usage of fuel, when compared with normal electrical generation.
The design of nuclear reactors has generally become centred around the generic type “Pressurised Water Reactor”. Whilst many other reactor systems have been demonstrated, this system has come into common use, and yields the advantages of accumulated knowledge. This factor is well demonstrated by the very effective nuclear power system developed in France, with 59 nuclear power plants producing over 80% of the country’s electricity.
The safety of nuclear reactors has been of primary importance. During the whole history of the nuclear power industry, only three significant accidents have occurred in which radio-active materials have been released to the atmosphere, and only one, Chernobyl, in which lives were lost.
Anxiety over the use of nuclear power is centred chiefly upon the production of highly radio-active waste. Two types of waste originate in the reactor; highly active fission products, and very long lived “actinides”, heavy elements similar to uranium.
Because the fission products are so highly active, they are consequently relatively short-lived, decaying to only one thousandth of their activity in about 350 years, and one millionth (similar to granite), in about 750 years. The actinides, being very long lived dissipating their half of their activity over very many tens of thousands of years, are only weakly radio-active.
The amounts of the fission products to be safely “disposed of”, is quite small, but gives rise to great anxiety, which is ill-founded. The method of disposing of this waste is to incorporate into a glass which is melted into sealed stainless steel vessels. These containers may then be stored in underground vaults in secure sites. Kept behind several metres of dense concrete, they present no danger to the public, and simply decay.
The scientific basis upon many Governments are acting to “fight global warming”, is far from clear. Many business interests have very strong lobbies stressing the imminent catastrophic danger of “climate change”. Evidence over many tens of decades, running into centuries, does not support the concept of an increase in extreme events, coincident with the increase of man-made CO2. Climate change as a natural variation certainly occurs quite independently of the assertion that man-made CO2 is altering the Earth’s weather patterns beyond recovery.
The evidence from the examination of the Vostok Ice Cores over many tens of thousands of years has revealed that it is temperature changes lead fluctuations of the CO2 content of the air, not that CO2 changes influence global temperature, as Government policy would have it.
There are, however, other significant influences upon global temperature and thus climatic conditions.
The first is the presence of water vapour in the atmosphere, just over sixty times more abundant than carbon dioxide, and with similar greenhouse gas properties. The world would be well below zero Celsius if it were absent, and its effects dwarf those of carbon dioxide.
The second is the interactive effect of variations in the activity of the sun, and cosmic radiation. Studies have shown that the resulting variation in cloud nucleation has a demonstrable effect upon global temperatures.
The present global temperature stasis is associated with a decrease in sunspot activity, and thus greater cosmic ray flux in the terrestrial atmosphere, which gives rise to increased cloud nucleation and cloud formation, thus lowering global heating effects.
Recent detailed studies of variations in the Earth’s orbit and inclination show that they give rise to global warming effects.
These effects are not at present considered in current thinking, a vacuum possibly encouraged by the huge profits resultant upon “fighting CO2 and climate change”.
In short, “if it ain’t broke, don’t mend it”.
This document was written by R H Phillips, a retired research scientist, who spent the last 35 years of a professional career at the Atomic Energy Research Establishment at Harwell in Oxfordshire.Since retirement he has continued to take a keen interest in all energy matters, and has a wide circle of very experienced contacts in all aspects of the industry. He has thus acquired a wide knowledge of the spectrum of energy matters from nuclear generation to renewables. He became, by examination, an Associate of the Royal Institute of Chemistry in 1954, and was elected a Fellow in 1971.Richard Phillips