April 15, 2009
Blogactiv wants to help its readers to better understand the world. Climate change is one of the big challenges of this century and it is a complex issue. It is therefore appropriate to give an overview. Eberhard Rhein, who regularly writes on energy and climate, had lectured on the subject in Malta earlier this spring. He has revised his text for publication by blogactiv.eu and you will therefore be able to read the comprehensive text of his lectures in the coming weeks. This is the second of six chapters.
The word climate is derived from the Greek “klinein”, which means inclination. The 23.5 degree inclination of the earth’s axis in relation to its rotation is fundamental for the earth’s climate: The inclination of the axis is responsible for the varying solar irradiation at different parts of the globe, which in turn conditions the direction and intensity of winds (together with the earth’s rotation).
Without the inclination we would have no seasons, and agriculture would not possible in the most northern or southern parts of the planet.
Climate describes the permanent, recurring features of the weather, which is a short-term phenomenon. Different parts of the earth are marked by different types of climate (tropical, arid, moderate, climate zones).
Since the earth was created about 4.5 billion years ago, the earth’s climate has changed continuously. It has progressively cooled due to changes in the composition of the atmosphere and enabled life to start on the planet.
These changes took place at extremely low pace. Usually they were the consequence of changing rotation parameters of the earth or neighbouring planets, sometimes also of meteors striking the earth’s surface. Rotation parameters change in times scales of 20 000, 40 000 and even 100 000 years.
Such changes have led to variations of the average temperatures between 12 and 17 centigrade, reflecting the advance and retreat of polar ice.
The last such – natural – change lasted about 10 000 years, the so-called Ice Age, when glaciers covered large areas of the northern hemisphere. It ended 10 000 years ago.
From the end of the last Ice Age to 1850 the global climate has been stable, with warmer and colder years/decades, but no trend in one or the other direction. But we have registered one anomaly, the Small Ice Age, from 1550-1850, during which both temperatures and C02 concentration in the atmosphere were below present levels.
Since 1970 the earth’s climate is changing at a breath-taking speed, never before registered in the past 600 000 years.
This change is essentially due to rising concentrations of what are called green house gases, above all C02 and CH4, in the atmosphere.
This in turn is the result of steeply rising emissions of all green house gases (+70 percent between 1970 and 2004), resulting from an extremely rapid development of human activity, above all the burning of fossil fuels, across the earth. There can therefore be no longer any doubt about the anthropogenic origin of the accelerating climate change. Humanity therefore has to stop it; it has the means to do so, provided it can muster the necessary political will and transform it into meaningful climate policy action. It is wrong to attribute climate change to the lack of energy alternatives or financials constraints. The main cause of continued climate change is the inability of focusing the necessary political efforts on the issue.
If humanity fails to substantially reduce green house gas emissions in the coming decades, living conditions for humanity and for most animal and plant species will profoundly deteriorate in the course of this and following century.
Climate change will generate higher air and water temperatures. Since 1900 average air temperature has risen by 0.7°, compared to a stable temperature of around 15° since the last Ice Age. The warmest 10 years registered since 1900 occurred since 1990!
Rising temperatures provoke more instable weather conditions, more droughts, floods, more intensive hurricanes, progressive melting of Alpine and Himalaya glaciers (which may lose up to one third of their surface until 2030!). They will lead to more extinction of plant and animal species. They are likely to destroy what remains of tropical forests in Brazil, Congo, and Indonesia etc.
Deserts will expand substantially on all continents, and rising water scarcity may in due time make it impossible to sufficiently feed humanity projected to rise to- unbelievable – 9 billion human beings by the middle of the 21st century.
In due time, the rise of temperatures is bound to lead to the progressive melting of the Greenland inland ice, which will raise sea levels by up to 7 meter and flood major coastal areas and city regions on earth.
No region on earth will escape the impact of climate change. But change will hit different parts of the planet with variable intensity. The plains of the Indian subcontinent and China will be among the most severely hit. So will be the countries around the MED, Australia and the southern USA, due to increasing droughts. The moderate zones in Asia, Europe, North and South America will be relatively spared.
Human knowledge about climate has increased vastly in the course of last 40 years, thanks to better measuring through satellite pictures, deep-ice boring, advance of climatology, climate – palaeontology and earth science.
In 1958, the first global measuring station of C02 emissions was installed on Hawaii. Today we dispose of a wide network of meteorological stations measuring emissions of various green houses gases. In addition, scientists have proceeded with extensive surveys of arctic ice.
Until the middle of the 18th climate change has been due to “natural” causes.
Human beings were unable to have any impact on nature and climate. Their numbers were small. By 1750 the population of the globe had hardly reached 1 billion people, roughly 10 percent of what it is today.
Their energy consumption was insignificant, say 1 percent of the today’s average energy consumption of US citizens, and it consisted 100 percent of renewable sources, wood and animal dung for heating and cooking, drought animals and hydro power for transport and agriculture.
Several least developed countries, in Africa and South Asia, e.g. Chad or Ethiopia still depend almost exclusively on traditional energies, in particular brush wood and solar heat. Their per capita emissions of C02 remain negligible (100-200 kg p.a.), i.e. about 1 percent of EU or US per capita emissions.
Their way of life makes them incapable of doing any harm to the climate.
The industrial revolution starting in the middle of the 18th century has been the turning point for the global climate. Man started to emit carbon dioxide by burning more forests than newly planted and using fossil energy, after the discovery of coal.
The deforestation of certain European regions in the 18th century led to the first environmental crisis, but also to modern forest methods based on the principle of sustainability.
Since then, human energy demand has grown exponentially, due to rapidly rising population and ever higher per capita energy needs.
In its irresistible thirst for energy, humanity tackled one new source of energy after the other:
1930 large-scale hydro
1980 wind and solar
2005 oil sands
2050 nuclear fusion?
Fossil energies like lignite, coal, oil or natural gas, are nothing but stored biomass, generated by photo-synthesis during hundreds of millions of years. They contain carbon and hydrogen.
Burning fossil energies releases C02. It is the C02 that creates problems. Part of it is stored by trees and other vegetation that “accumulate” them as biomass. Another part is stored in the Oceans where it helps “feeding” sea biomass like algae. Humanity presently emits some 30 billion tons annually, of which about half goes into the atmosphere, the other half being absorbed by biomass on earth and the sea. But both the sea and forests have a limited storage capacity. Recently scientists are getting scared about these “sinks” because of deforestation and rising acidity of the oceans.
Increasing C02 quantities therefore rise into the atmosphere where they stay some 100 years, changing the composition of the gaseous shield in the atmosphere in a dramatic way and causing climate change on earth.
It is therefore important to understand the basic functioning of the atmosphere for the global climate.
The earth is surrounded by the atmosphere (composed of the troposphere up to 10 km, Mt. Everest!) and the stratosphere (10 – 40 km).
The atmosphere contains two major gases: Nitrogen 78 percent and oxygen 22 percent, plus Argon 1 percent.
Were the planet only surrounded by these three gases, the earth’s temperature would be around -18°, and the planet an icy desert, without any signs of life, like Mars.
We owe life to the existence of a few other gases, of which only marginal quantities are found in the atmosphere. The most important among these are hydrogen in the form of steam/clouds, followed by carbon dioxide, ozone, nitrogen-oxide and methane.
These gases have two separate functions.
- Ozone protects us against excessive and destructive UV irradiation.
- The other four form a natural regulator of temperature. They shield us against excessive heat and cold by offering a natural “green house effect”. They operate like a glass house, which allows sun light to enter and absorb most of its heat. These green house gases warm the earth surface by incredible +33°, enabling the average surface temperature to reach 15° and not -18°, as it would without the gas shield. Over time the influx and outflow of solar energy has been miraculously balanced to an inflow and outflow of solar radiation as to keep the earth’s temperature within a range of 12-17 degrees.
Since the beginning of industrialisation (1750) the concentration of green house gases has risen substantially: CO2 by 30 percent, methane by 150 percent and nitrogen – oxide by 17 percent. Their concentration keeps rising as they stay in the atmosphere for many years/decades
(C02 for 100 years, methane for 12 years, NO2 114 years) and the volume of additional emissions keeps rising.
During the last 600 000 years, the C02 concentration has never reached the present high levels of close to 400 ppm. (0.04 percent) It has varied between 200 and 300 ppm, with the lowest level of < 200 ppm during the last Ice Age 10 000 years ago. During that long time climatologists have observed a net correlation between levels of C02 concentration and temperatures.
It is the anthropogenic increase of green house gases that constitutes the core of the climate problem. The natural gas shield of the atmosphere is extremely sensitive; any change in its composition will be felt, with a certain delay, by higher temperatures on earth and in the atmosphere, with multiple consequences for the climate.
In 2000, the composition of the three main green house emissions was as follows (billion tons, UN Global Resources Institute)
Total 33 (in C02 equivalents)
The origin of global C02 emissions by sectors was as follows: (percentages, in 2000)
Power and heating 37
Other energy industries 5
Residential Housing 8
Agriculture, Trade, 6
This table does not take into account the C02 emissions due to deforestation, which are estimated at 20 percent of total!
Between 1950 and 2000 humanity emitted a total of 800 billion tons of C02, of which 300 billion from Europe, 200 billion from the USA, 77 billion from Russia, 70 billion from China and 36 billion from Japan. During the first decade of the 21st century the cumulative emissions have surged further due to the unprecedented economic growth until 2008.
If left unchecked, the C02 concentration of the atmosphere is expected to reach some 600 ppm or even more by the end of the century. This might lead to a rise of average temperature by 4-6° and have dramatic consequences for living conditions on earth.
Even if humanity stopped emitting greenhouse gases as of todayGgd GdddfGGHGGGG of today, climate change would continue during the next decades because of inertia. Temperatures would not go back to their pre-industrial levels.
A fortiori, any additional emission, however small, will lead to more C02 concentration in the atmosphere and influence the temperatures etc. for many decades, including through secondary effects, e.g. releasing tundra methane, destroying tropical forests and reducing the capacity of the oceans for storing additional C02 (sinks), which we normally tend to ignore.
The costs of climate change will be enormous. Sir Christopher Stern, the author of the “Stern Report” (2006), has estimated they might reach up to one fifth of the global product by the middle of the century, in a business as usual scenario. Expressed in very rough monetary terms, this may be equal to an annual cost in the order of $ 20 000 billion! Most costs will arise for adapting to climate change, including resettlement of hundreds of millions of migrants, profound adjustments of industrial structures, repair and rebuilding of existing infrastructure etc.
Compared to these incredibly high costs, the costs for keeping climate change within acceptable limits are tiny, some 1-2 percent of the global product today ($ 500 billion), no more than an insurance premium, and much less than humanity spends presently on “defence” (3 percent).
Measured in economic, human and environmental terms the damage will become incalculable, as climate change will become irreversible beyond a critical threshold that we may reach in a few decades, if we fail to turn back the movement.
It is therefore imperative to reduce the volume of green house gas emissions at the earliest possible level. The more humanity delays the necessary trend reversal, the more future generations – beyond the 21st century – will suffer from climate change. The objective should be to phase them out altogether well before the end of century. To reach this, emissions should their peak around 2020 and fall thereafter by at least 50 below 1990 levels until 2050.
Despite the overwhelming scientific evidence of the ongoing climate change and its severe consequences, the international system seems unable to react timely and effectively.
Seven basic obstacles stand in the way of rapid and effective action against climate change. It is important to understand these.
Slowness of the process:
Climate is a “common good” of humanity, which everybody takes for granted. We cannot feel its slow destruction. Few people dare to establish a correlation between short-term deteriorations of weather conditions and long-term climate change. The first ones are visible but the reasons behind them are complex; a normal human being finds it difficult to understand them and does not care as long his house is not destroyed by a thunderstorm or extreme floods.
The change of climate is not visible world-wide or simultaneously.
Droughts in California, southern Australia, Argentina, the eastern MED are rarely put in a global context. Changes in temperatures of the oceans or their acidity are only visible to the few scientists who closely observe them. Only few political leaders have gone to Greenland or the Arctic Circle to realise what climate change means in reality.
More dangerously even, the younger generations have no memory of what the climate conditions had been 30-50 ago! They grow up in metropolitan areas with little direct touch to nature and no solid grasp of scientific phenomena!
Addiction: All of us have got addicted to fossil energy in all its forms – automobiles, aircraft, electric power, central heating – that we cannot imagine life without. So we prefer to go business as usual.
Vested interests: Utilities, automobile, aircraft companies etc have invested huge amounts in the generation and use of fossil energy and continue to do so. They do not want to see the value of those investments depreciated by alternative energies. The big energy companies have been the most powerful opponents against a forward-looking climate and energy policy. This has been all too visible in the USA.
They simply cling to the product and technology they know best: fossil energies.
Cheapness: Market prices for fossil energy are lower than those of alternative energies, except hydro and, possibly, nuclear power, because they fail to take incorporate the “external costs” they cause to the environment and climate: “biggest failure of the market economy” (Sir Nicholas Stern).
Discounting the future: Human beings discount future pains and satisfactions. Climate change appears distant. Even in its worst consequences, it does not appear as a mortal threat. Citizens therefore fail to feel concerned about it, contrary to many more direct threats like unemployment, health risks or the security of their savings.
This is probably the single most important impediment against taking action on time. It makes it so difficult, even for wise politicians to take society with them.
Lack of commitment by the political class and the elites: They do not feel under pressure from their voters. Elections are not yet won on climate policy! When they will one day, it might be too late to do something effectively about it.
Need for global action: Whatever individual countries or even the EU may do to reduce emissions of green house gases, will fail to have the required impact on the global climate. Major emitter countries will have to act in concert. This further complicates matters, because industries pretend they will be hurt by climate policy measures, and loses international competitiveness (the so-called effect of “carbon leakage”).
That is why the short history of international efforts to cope with it is so full of disappointments and contains so little to rejoice at.
Eberhard Rhein 07.04.09Author : Eberhard Rhein