by L. Berney
This is an update of a previous article.
THE PROBLEM
Since the formation of planet Earth, the climate has always changed and it is still changing. Changes to the Earth's climate are in the main caused by changes in the Earth's temperature. There have been warm periods when there was no permanent ice at either pole. There have been Ice Ages: at one period some 30% of the Earth's surface was under permanent ice. Over time there have been many warm/cold cycles.
The last Ice Age ended some 10,000 years ago; since then, the Earth's temperature has been slowly rising and is still rising and, presumably, it will continue to rise until at some time in the future the temperature will start to fall again. These temperature rises and falls do not occur evenly; it seems there are intermediate warm/cold swings along the way. Some 2,000 years ago in Roman Britain, along the South coast, there were many vineyards - the temperature must have been warmer than it is today. About 500 years ago there was a 'mini Ice Age' lasting several decades.
What factors cause the temperature/climate to change? One of the major factors is the Sun: the heat radiating from the Sun is not constant. At some periods the Sun radiates more heat than at others and the temperature of the Earth follows suit. Another major factor is what is known as 'the greenhouse effect'. The Sun heats the Earth's surface; some of that heat is reflected back off the surface; part of that reflected heat goes back out into space, part is trapped and retained by clouds and by certain gasses in the atmosphere, known as 'greenhouse gases'.
The greater the cloud cover and/or the greenhouse effect, the warmer the Earth's temperature, and vice versa. By far the greatest 'greenhouse effect' is caused by clouds: it is common knowledge that at night, when no heat is being radiated by the sun, the air temperature drop is greater when there is no cloud cover, and is less when there is. In fact, life on earth as we know it is only possible BECAUSE of the green house effect; without it, the earth's temperature would be 30ºC to 40ºC lower and the planet would be more or less permanently covered by ice.
These and several other factors interact with each other; as a result the Earth's temperature and therefore the climate has always been and always will be unstable.
Records undeniably show that the Earth's temperature is increasing and has been increasing for many thousands of years, since the last Ice Age 10,000 years ago - we are currently in a cyclical period of 'Global Warming'. In the 20th century, the average temperature is said to have increased by 1ºC. There are many estimates as to how much the temperature will increase by the end of this century; most predictions indicate an increase of between 3ºC and 6ºC. The accuracy of such projections is open to question. We all know the inaccuracies in projecting the weather even a few days ahead; projecting the Earth's temperature 100 years ahead...?
GREENHOUSE GASES AND CARBON DIOXIDE
The 'greenhouse gases' which give rise to the 'greenhouse effect' are carbon dioxide, methane and nitrous oxide; together, they comprise less than 1.0% of the Earth's atmosphere. The gas which scientists think is responsible for most of the greenhouse effect is carbon dioxide (CO2). Some facts about CO2:
- Comparison over the millennia of the Earth's temperature and the level of CO2 in the atmosphere show a marked correlation. In warm periods, the CO2 levels were higher; in cold periods, they were lower.
- The greatest repository of CO2 is the sea (71% of our Planet's surface is sea). If the sea temperature rises, it releases CO2 to the atmosphere; if it falls, the reverse happens, the sea absorbs CO2 from the atmosphere.
- Forests and vegetation absorb CO2; warmer temperatures encourage plant growth and therefore the absorption of CO2 is increased.
- Burning of fossil fuels - coal, oil, natural gas - creates CO2; cutting down the rain forests (e.g. in Brazil) reduces the absorption of CO2; forest fires (man-made and natural) create CO2.
- Until the middle of the 19th century, the start of the industrial revolution, the volume of CO2 in the atmosphere was about 0.027%; currently it is up to 0.038%;
The two most important results of the increasing temperature, and the consequent changes in climate, are these:
- Change in the distribution and amount of rainfall leading to changes to rivers and lakes resulting in 'desertification' of some previously productive areas, increasing agricultural and livestock productivity in others.
- Melting of the ice cover in Greenland and Antarctica and glaciers elsewhere leading to a gradual rise in the sea level world-wide.
- a rise in sea level of one meter would inundate a large part of Bangladesh, Holland, Venice and many of the world's low-lying areas
- it would inundate a number of populated islands
- it would inundate large areas of Southern USA.
About 20 years ago, scientists started to issue warnings that the CO2 being added to the atmosphere by man's activities - burning of fossil fuels and clearing of forests - was beginning to cause the Earth's temperature to rise which in turn would cause the climate to change. In the 1980s the Inter-governmental Panel on Climate Change (IPCC) was formed to report on the problem. The IPCC reports about every five years. The last IPCC report was issued in February 2007.
As confirmed by the IPCC, we know for a fact that the Earth's temperature is rising and we know that the CO2 level is rising too. It is the majority scientific opinion that it is the increase in the CO2 level, rather than a "natural cause" cyclical increase in the Earth's temperature, which is causing the current temperature rise and that the increase in the CO2 level is caused by mankind's burning of fossil fuel.
Some scientists believe that the amount of man-made CO2 which has already been released into the atmosphere over the last 100 years has irreversibly tipped a delicate balance which will result in the Earth continuing to warm for at least the next hundred years, even if NO further CO2 was added to the atmosphere.
Other scientists (the "sceptics") think that the observed increase in the CO2 level is not the cause, or only a small part of the cause, of the rise in the Earth's temperature. The argument supporting this view is that the increase in volume of CO2 in the atmosphere over the last 100 years is a very small 0.11%, up from 0.27% to currently 0.38%. Even if all of this increase had been man-made, could this very small percentage increase of CO2 in the atmosphere cause a significant increase in the Earth's temperature? They think not. They think the increase in temperature is due one of the Earth's natural cyclical warming periods.
These scientists also make another point: while ice core samples show that, over millions of years, there is a correlation between the CO2 level and the average temperature, the evidence is that the rises in the CO2 levels FOLLOWED the rises in temperature. This, they say, indicates that it is more likely that the rises in temperature CAUSED the rises in the CO2 level, not the other way round.
It is, perhaps, worth noting here that in the 1970s, just 30 years ago, scientists were predicting that the Earth was probably entering the next cooling period, heading towards the next ice age!
"DOING SOMETHING ABOUT IT"
(Note. Climate Change jargon. Mitigation: actions to stop or slow down climate change. Adaptation: actions to adapt to a changed climate)
In the last few months there has been a notable upsurge in the public awareness of the possibility, and possible outcome of climate change. Hardly a day passes when there is not some reference to 'global warming', 'climate change' and 'carbon emission' in the media. This is remarkable since scientists raised the matter over 20 years ago!
Popular opinion, pressure groups and environmentalists have forced the world's political and business leaders to think that they ought to "do something": but do what?
It seems that these leaders (or most of them) have decided to assume that as global warming is being caused, or mostly caused, by the increase in the amount of CO2 in the atmosphere due to the burning of fossil fuels, if the production of man-made CO2 were to be reduced, the Earth's climate would respond by ceasing to get any warmer and the problem would be solved.
Based on that unproven simplistic assumption, our leaders have decided to take positive steps to drastically reduce the amount of CO2 released to the atmosphere. Starting recently, they are introducing laws and initiatives to put this policy into effect. For example: a vast increase in the installation of Wind Generators (hundreds to be mounted in the estuary off the Kent coast and IN the North Sea off Scotland at a cost of œ2.5 Million each!); installation of solar panels; the international "Emission Trading Scheme" ("ETS"), financial incentives for industry to reduce emissions, "emission reduction targets" and the allocation of "carbon permits"; this has given birth to "carbon trading" - there is now a multi-million dollar 'market' in buying and selling carbon permits!
All developing nations want to raise their living standards to those of the developed world. To do that requires more power - lots more power. The world situation in which these 'reduce CO2' policies are to be implemented coincides with pressure for more power and thus to generate more CO2, not less. One expert's prediction is that, by the end of this century, the world's energy requirements will be FIVE TIMES the present output!
This pressure by the developing world for more power is increasing and is set to go on increasing. For example, China is opening one new coal-burning, CO2 spewing, power station per week! India's power requirements, mostly coal fueled, are increasing exponentially. In Africa, the energy consumed per head now is only 10% of that consumed per head in the USA; international efforts are under way to 'lift Africa out of poverty' which inevitably will require a great deal of power.
The 'developed world' is urging the 'developing world' to cut down their CO2 emissions. The 'developing world' is resisting - their argument runs: "Since the 20% of the population in the 'developed world' produce 80% of the CO2 why should we be expected to hold back on lifting ourselves out of poverty, to hold back our use of energy? - Let the developed world cut back on theirs first!"
Another factor is that the world's reserves of oil and natural gas are being used up rapidly. These sources could be, and probably will be, replaced by an increase in the use of coal of which there are still vast reserves. Coal produces much more CO2 and other emissions than oil or gas so that for the future the CO2 problem is likely to be exacerbated.
Underlying the present world situation, the human population is predicted to increase by some 50% in the next 50 years -- another 3 Billion power consumers!
For these practical reasons, it seems to me improbable that the volume of man-made CO2 being generated can even be held at its present level - to reduce it from its present level is even more improbable.
MY CONCLUSION - WE ARE HEADING IN THE WRONG DIRECTION!
From the evidence it seems that for the foreseeable future, the Earth probably WILL get warmer, the climate probably WILL change, the sea level probably WILL rise. I suggest that whatever policies we might adopt, aimed at mitigating and adapting to the effects of Global Warming, they need to be based on these facts. I suggest the current "solutions", focused mainly as they are on the reduction of CO2, are bound to fail.
The man-made CO2 being released to the atmosphere may be, and probably is, adding to the rate of cyclical or natural warming. But it is not, on its own, the SOLE CAUSE of the current temperature rise. The Earth is in one of its natural cyclical warming periods and it will be getting warmer even if NO man-made CO2 is released. If man-made CO2 emissions were to be reduced, even if they were stopped entirely, the only result would be, perhaps, to slow slightly the rate of warming - it would not halt it.
The decision of our politicians to try to stop the Earth getting warmer by embarking on programmes to reduce the volume of man-made CO2 brings to mind the experience of King Canute who tried (and failed) to stop the tide from rising.
Moreover, the amount by which the present policies will reduce the total carbon emission IF IT REDUCES IT AT ALL is infinitesimal compared to the world's increasing energy requirements.
In fact the current moves and financial incentives to cut down CO2 emission are, in my opinion, doing more harm than good. New taxes are being planned, the airline and holiday industry is going to be hit, poor countries are not going to able to sell their farm produce to rich countries because of the "air miles" involved, a new non-productive industry is forming to advise on how to make a profit on carbon credit trading etc. I believe the steps being taken to try to reduce
CO2 emissions will inevitably be costly and may, and almost certainly will, have a negative effect on the world's economy. These steps will never achieve their objective - they are futile and useless, and a waste of valuable resources.
Worse, the current policies are diverting our attention from facing up to reality and to mankind's looming problems, namely that the Earth IS warming and probably WILL GO ON warming for the foreseeable future, regardless of whether or not we reduce man-made CO2.
We are, in my opinion, heading in the wrong direction!
WHAT SHOULD WE DO?
If, as it seems, the Earth is undergoing one of its warming cycles, there is nothing mankind can do to stop Global Warming. What, in my opinion, we need to do is to accept that in all probability Global Warming is here to stay and to address its inevitable results. The world's effort and energy currently being directed towards halting Global Warming by reducing carbon emission (a policy doomed to failure in my view) needs to be re-directed toward the following three main objectives.
- NEW DEVELOPMENT - DUE TO CLIMATE CHANGE - As explained above, there will be serious problems caused by changes in the distribution and amount of rainfall. There probably will be floods and droughts, changes in the distribution and availability of water for consumption and food production,.increasing 'desertification' making more areas barren and uninhabitable. These problems will gradually occur over decades. Mankind is adaptable -- I believe that over time new areas will have to be developed and populated and some existing areas will have to be abandoned. Every country should start planning now for the gradual creation these new development areas.
- NEW DEVELOPMENT - DUE TO RISING SEA LEVEL - The problem presented by the gradual raising of the sea level needs to be addressed, not by a 'King Canute' solution, but by accepting that the sea level will probably rise and go on rising for the foreseeable future. Every country with coastal areas needs to start planning accordingly. Plans need to be drawn up to establish the areas of land which will be inundated if/when the sea and river levels rise by, say, two meters. Over the coming decades all the housing, agriculture, commercial, roads, railways and other installations and activities taking place in those areas will have to be re-established on higher ground. In contrast, due to Global Warming, large area in the Northern Hemisphere currently ice-bound will become ice-free and will be available to be developed and utilized. The first step would be to prohibit any new construction in endangered areas; to allow building only in the newly designated development areas.
- POWER SUPPLY - Solution of the problems which will arise due to carbon emission, climate change and a rising sea level are inevitably linked to the problem of the world's future power supply. The world needs an ever increasing supply of cheap power which could amount to five times the present level by the end of this century. The production of this power should not pollute or add greenhouse gasses to the atmosphere. Accordingly, our need and use of fossil fuels should gradually be eliminated (the remaining reserves of oil and gas will in any case be exhausted in the not too distant future). For road vehicles, an alternative to petrol/diesel will have to be employed. The alternative is, I suggest, either electric batteries, or hydrogen fuel cells or hydrogen powered internal combustion engines, or a mixture of all three. The hydrogen gas would be manufactured using electrical power. What source(s) of energy could supply the power the world needs? Firstly, I believe the amount of the power which could be generated by the 'replaceables' wind, solar, hydroelectric, wave and tide power can not even begin to meet the world's future needs. Moreover, the money and material being expended on them is, I suggest, an irreplaceable waste of the world's resources. All the world's needs could be met, partly or in whole, by nuclear power. In spite of the known disadvantages, nuclear power is one of the only possible practical solutions. (Note that today, 80% of the France's electricity power is generated by nuclear power stations.) The other source of energy which could be harnessed is geothermal (hot rock) power; that is the extraction of heat from the earth's crust by mining (wells), similar to mining for oil and gas. Geothermal energy has distinct advantages over nuclear and, in my opinion, its rapid development should be vigorously pursued, if necessary using tax incentives. (A description of geothermal technology is appended.) Nuclear fusion is another possible source of energy but this technology is only in the theoretical stage; it will be many years before nuclear fusion will be commercially available, if it ever is.
A question which obviously presents itself is this: are the massive developments
in new locations envisaged above a practical possibility?
In 1950 the population of the world was 2,500 million; now, 57 years later it is 6,600 million. There are now 4,000+ million additional people in the world but homes, work places and the infra-structure for all these 4,000+ million additional people have been built, all constructed in the last 57 years. For example, Abuja (Nigeria), current population 4,600,000, was built on what was bare ground only 30 years ago. Shanghai, population now 17,500,000 -- 6 years ago it was 10,000,000.
I suggest that, spread over 100 years, the establishment and developments of new population centers is far from impossible, it could be done.
Another question is: is the provision of the enormously increased future power requirements and, simultaneously, the elimination of the use of fossil fuels by the installation of nuclear and/or geothermal power a realistic possibility?
In the world today there are over 500 nuclear power stations in operation and some 50 more under construction. The uranium they use is in plentiful supply. There are the problems of disposal of nuclear waste and social acceptance but, over time, and our way of life faced with a 'Hobson's choice' situation, I believe those problems would be overcome.
Geothermal (hot rock) technology is still in the trial stage, although a test plant in Australia is said to be working well. The management there say that in the area around the test site alone there is enough heat underground to generate enough electricity to power the whole of Australia! The mining technology is well established; it is virtually the same as that used for drilling oil wells. The electrical generating plant is standard except that the source of the heat required is geothermal instead of from burning fossil fuel.
Based on the volume of the construction of nuclear power plants and oil wells in the last century, I believe that nuclear and/or geothermal fueled electrical power plants coupled with hydrogen generation plants (in lieu of oil refineries) could supply all the world's power needs for the foreseeable future AND simultaneously eliminate the use of fossil fuels
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APPENDIX
GEOTHERMAL ENERGY FACT SHEET
INTRODUCTION
The word geothermal comes from the Greek words "geo" (earth) and "therme" (heat), and means the heat of the earth. Earth's interior heat originated from its fiery consolidation from dust and gas over 4 billion years ago and is continually regenerated from the decay of radioactive elements that occur in all rocks.
EARTH'S HEAT AND VOLCANIC REGIONS
It is almost 6,500 kilometres (4,000 miles) from the surface to the centre of the Earth, and the deeper you go, the hotter it gets.
The outer layer, the crust, is three to 35 miles thick and insulates us from the hot interior. From the surface down through the crust the normal temperature gradient (the increase of temperature with the increase of depth) in the Earth's crust is 17 - 30°C per kilometre of depth (50-87°F per mile). Below the crust is the mantle, made of highly viscous, partially molten rock with temperatures between 650 and 1,250°C (1,200-2,280°F). At Earth's core, which consists of a liquid outer core and a solid inner core, temperatures may reach 4,000-7,000°C (7,200 to 12,600°F). Where magma reaches the surface it can build volcanoes. But most magma stays well below ground, creating huge subterranean regions of hot rock sometimes underlying areas as large as an entire mountain range. Cooling can take from 5,000 to more than 1 million years. These shallow regions of relatively elevated crustal heat have high temperature gradients.
RENEWABILITY AND SUSTAINABILITY
Production from individual geothermal fields can be sustained for decades and perhaps centuries. The U.S. Department of Energy classifies geothermal energy as renewable.
GEOTHERMAL TECHNOLOGY AND EQUIPMENT
The drill rigs and drilling technology and equipment are virtually the same as that used for drilling for oil or gas. The electrical generating plant, located alongside the geothermal well heads, is standard; steam turbine driven electrical generators connected to the grid. Water consumption is small as the steam is condensed and re-used as injection water.
PROTECTION OF THE ENVIRONMENT
With all sources of energy, developers and consumers must work to protect the environment. The challenges differ with the type of energy resource, and the differences give geothermal energy certain advantages. Geothermal direct use facilities have minimal or no negative impacts on the environment. Geothermal power plants are relatively easy on the environment. They are successfully operated in the middle of crops, in sensitive desert environments and in forested recreation areas.
VISUAL PROTECTION
No power plant or drill rig is as lovely as a natural landscape, so smaller is better. A geothermal plant sits right on top of its fuel source: no additional land is needed such as for mining coal or for transporting oil or gas. When geothermal power plants and drill rigs are located in scenic areas, mitigation measures are implemented to reduce intrusion on the visual landscape. Some geothermal power plants use special air cooling technology which eliminates even the plumes of water vapour from cooling towers and reduces a plant profile to as little as 24 feet in height.
IMPROVING GEOTHERMAL TECHNOLOGY
Since the 1970's the geothermal industry, with the assistance of government research funding, has overcome many technical drilling and power plant problems. As a result of government-assisted research and industry experience, the cost of generating geothermal power has decreased by 25% over the past two decades. Research is currently underway to further improve exploration, drilling, reservoir, power plant and environmental technologies. Enhancing the recoverability of Earth's heat is an important area of ongoing research.
ENHANCED GEOTHERMAL SYSTEMS
Private and government research projects in the United States, Japan and in Europe are improving the accessibility of geothermal energy by developing new technology to increase the permeability of the rocks.
Permeability can be created in hot rocks by hydraulic fracturing -- injecting large volumes of water into a well at a pressure high enough to break the rocks. The artificial fracture system is mapped by seismic methods as it forms, and a second well is drilled to intersect the fracture system. Cold water can then be pumped down one well and hot water taken from the second well for use in a geothermal plant. This "hot dry rock" technology is being tested in Japan, Germany, France, England and the U.S. In Australia a test plant has been in operation for some time yielding excellent results.
THE FUTURE FOR GEOTHERMAL ENERGY
The outlook for geothermal energy use depends on at least three factors: the demand for energy in general; the inventory of available geothermal resources; and the competitive position of geothermal among other energy sources. The Demand for energy will continue to grow. Economies are expanding, populations are increasing (over 2 billion people still do not have electricity), and energy-intensive technologies are spreading. All these mean greater demand for energy. At the same time, there is growing global recognition of the environmental impacts of energy production and use from fossil fuel and nuclear resources. Public polls repeatedly show that most people prefer a policy of support for renewable energy.
The critical temperature for the generation of geothermal energy to power an electrical generating plant is 200ªC. At every point in the world a well will reach rock at that temperature; on average the depth to reach a temperature of 200ªC is about 5Km. Geothermal heat is more accessible in some areas than others but the inventory of accessible geothermal energy is sizable. The entire world resource base of readily accessible geothermal energy has been calculated in government surveys to be much larger than the resource bases of coal, oil, gas and uranium combined. The geothermal resource base becomes more available as methods and technologies for accessing it are improved through research and experience.
See: www.geodynamics.com.au
COSTS
Shorter and Longer Term Costs. Production of fossil fuels (oil, natural gas and coal) are a relative bargain in the short term. Like many renewable resources, geothermal resources need relatively high initial investments to access the heat. But the geothermal "fuel" cost is predictable and stable. Fossil fuel supplies will increase in cost as reserves are exhausted. Fossil fuel supplies can be interrupted by political disputes abroad.
Renewable geothermal energy is a better long term investment.
Direct and Indirect Costs. The monetary price we pay to our natural gas and electricity suppliers, and at the gas pump, is our direct cost for the energy we use. But the use of energy also has indirect or external costs that are imposed on society.
Examples are the huge costs of global climate change; the health effects from ground level pollution of the air; future effects of pollution of water and land; military expenditures to protect petroleum sources and supply routes; and costs of safely storing radioactive waste for generations. Geothermal energy can already compete with the direct costs of conventional fuels in some locations and is a clean, indigenous, renewable resource without hidden external costs. Public polls reveal that customers are willing to pay a little more for energy from renewable resources such as geothermal energy.
Domestic and Importing Costs. Investment in the use of domestic, indigenous, renewable energy resources like geothermal energy provides jobs, expands the regional and national economies, and avoids the export of money to import fuels.
Energy demand is increasing rapidly worldwide. Some energy and environmental experts predict that the growth of electricity production and direct uses of geothermal energy will be revitalized by international commitments to reduce carbon dioxide emissions to avert global climate change.
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