The Future of Planet Earth


This presentation is dedicated to the Chinese Yangtze river dolphin (also known as "the goddess of Yangtze") which, as of several weeks ago, is now "functionally extinct" [1] following a six week survey that resulted in 0 sightings. The species declined over decades due to a variety of causes, including the building of the Three Gorges Dam, environmental degradation, loss of food supply in the river, electric fishing, noise pollution hunting by humans, and collisions with ships.

It had previously been on the planet for over twenty million years.


The purpose of this presentation is to provide an introduction to the environmental and ecological challenges that the planet faces over the next hundred years or so. The presentation neither seeks to alarm or to appease, but rather to provide a summary of the conventional scientific knowledge that is available. It will going to concentrate on the limits and damaging effects of modern industrial growth on the environment and the ecological balance, but also with some pointers concerning what constitutes genuine research in this field, as the message from the mass media can often be quite confusing, and even some cautious perscriptive suggestions.

The basic environmental problem of modern society can be stated as follows: The mechanisms for growth provide for a worldwide increase in production and population, the latter which is expected to reach ten billion by 2050 according to the United Nations. These increases have two material limitations; the supply of finite resources (everything from cultivable land and mineral resources) and the capacity of the ecosystem to absorb pollutants. Whilst both resource discoveries and efficient technological development can indeed reduce the negative effects of growth, one additional absolute limit can be stated - the capacity of the ecosystem to absorb heat from energy use. If economic growth involves increased consumption of energy and this energy is ultimately released as heat it is inevitable that this means, in the long run, increased global temperatures.

Thus there are three main environmental issues facing the future of planet earth (global warming, pollution and finite resources), which arise from two basic causes (energy use from economic and population growth). The following is an attempt is made to provide the best empirical and predicitive studies in relation to these issues.

Global Warming

Global warming is an observed fact of the increase in the average temperature of the Earth's atmosphere and oceans. In the 20th century the near-surface atmospheric temperature rose 0.6 °Celsius and particularly sharply in the last fifty years [2]. This variation is more significant than the "medieval warm period" of the 11 century, and is about the same as the "little ice age" of 16th to mid-19th centuries. The overwhelming scientific opinion is, as expressed by the Intergovernmental Panel of Climate Change, the U.S. National Academy of Sciences, the U.S. National Research Council, the American Metereological Society, and, as reported in Science in 2004, 100% of revelant articles from referreed scientific journals from 1999 to 2003, is that most of recent warming is due to human activity [3], especially the increased release of "greenhouse gases" such as carbon dioxide, from the burning of fossil fuels, land clearing and agriculture. Greenhose gas emissions account for a +0.7 °C change to temperatures over the last 100 years, solar and ozone changes to +0.2 °C and +0.1 °C respectively, sulphates to -0.25 °C and volcanic activity -0.15 °C. [4]

There is significant uncertainity in how much global tempratures will rise in this century, due to doubts on the volume of greenhouse gas emissions and questions of climate sensitivity. If there are stringent regulations or other means to reduce greenhouse gas emissions, for example, then obviously the temprature inceases will be significantly reduced. Current literature suggests an increase in the range of 1.5-4.5 °C. When the IPCC conducted its studies models predicted that global temperatures would increase by between 1.4 and 5.8 °C between 1990 and 2100 [5]. An increase in global temperatures cause other changes such as rising sea levels, increases the frequency and intensity of extreme weather events, changes to agricultural yields, glacier retreat, species extinctions and increases in the ranges of disease vectors.

From 3,000 years ago to the start of the 19th century sea level was almost constant, rising at 0.1 to 0.2 mm per annum; since 1900 the level has risen at 1 to 3 mm per annum; since 1992 satellite altimetry indicates a rate of about 3 mm per annum [6]. In 2001, IPCC's The Third Assessment Report predicted that by 2100, global warming will lead to a sea level rise of 9 to 88 cm. Glacial retreat is almost universal (mainly sections of Scandavia excluded) with cumulative mean thickness declining by some 14 meters since the mid-1950s, with the most extreme instances in New Zealand. [7] Very recently the University of Texas has noted population extinctions which they attribute to climate change which correlate to their predictions in terms of location but have occurred far sooner than expected [8].


In the broadest sense, pollution is all forms environmental contamination, including air, water, soil, noise, light, and even visual pollution. Vehicle emissions are the primary cause of air pollution with the World Health Organization estimating that 4.6 million people die each year from causes directly attributable to air pollution, including aggravated asthma, bronchitis, emphysema, lung and heart diseases, and respiratory allergies. Water pollution is a leading worldwide cause of deaths and diseases, and that it accounts for the deaths of more than 5.1 milion people per annum. Since eutrophication (damage to an ecosystem with chemical nutrients, typically compounds containing nitrogen or phosphorus) was recognized as a pollution problem in the mid-20th century, it has become widespread. Surveys showed that 54% of lakes in Asia are affected; in Europe, 53%; in North America, 48%; in South America, 41%; and in Africa, 28%. Soil contamination (usually benzene, mercury and polychlorinated biphenyl) also contributes to these health risks (leukemia, kidney and liver damage), both of direct contact and from secondary contamination of water supplies. Soil contamination also has significant effects on ecosystems, the most well known being the damage caused by persistent DDT material on avain populations, and alterations on plant metabolism, which reduce crop yields.

Until the early 1970s, there was little awareness of the worldwide problem of pollution and regulation was usually tied to very specific instances and indeed pollution was sometimes seen a social positive; there is a rather frightening old Soviet poster with a backdrop of smokestacks proudly proclaiming "The smoke of chimneys is the breath of Soviet Russia"). The U.S. National Environmental Policy Act of 1969, the amended Clear Air Act of 1970 (and especially the 1990 amendments which made real effort to internalise external costs), the amended Clean Water Act of 1977 and the Noise Control Act must be considered international milestones in attempts to reduce pollution through regulation. Nevertheless, the U.S. maintains a maximum fine of USD$25,000 for dumping toxic waste; many large manufacturers decline to dispute violations, as they can easily afford the fine.

Scientific debates over pollution usually concern themselves on whether specific contaminants affect only certain species or part of a species, whether there are additonal effects on biodiversity, whether the pollution causes contemporary or predicted future costs, is the direct cause of harm or acts in concert with other environmental instances, and the degree by which the employment or prosperity is dependent on the pollutant. Overall, it would seem that the pollution is still increasing. Both the regulatory regime and technological improvements have dramatically reduced the quantity of emissions per motor vehicle, but the quantity of people driving has increased at a greater rate. More successfully treaties like the Sulphur Emission Reduction Protocol which was entered in 1987 has significantly reduced the impact of "acid rain" in European forests where, according to a U.N. survey of 1986, 23% of all trees were moderatly or severely damaged.

Finite Resources

Natural resources are usually classified into renewable and non-renewable resources. Renewable resources are generally living resources (fish, wild animals and forests, for example), which can rebuild themselves if they are not overharvested. A non-renewable resource is a natural resource that cannot be re-made or re-grown, such as fossil fuels, which have a high carbon content because their origin lies in the photosynthetic activity of plants millions of years ago.

In 1970 the Club of Rome published "Limits to Growth", which contained some rather pessimistic predictions concerning the quantity of non-renewable resources, including near exhaustion of oil, natural gas, silver, tin, uranium, aluminium, copper, lead and zinc. These predictions proved to be quite inaccurate - in every case except for tin, known resources have actually grown since the report. The publication tended to assume that whilst pressures on the environmont would increase exponentially, technological changes would occur in a linear fashion and that known resource reserves had largely reached their limit. Such poor methodology was quite unnecessary if the point was to illustrate the exhaustion of finite resources as well shown by Marion Hubbert's peak oil theory (routinely used by oil companies).

Renewable resources themselves are prone to destruction if overused. Deforestation and desertification are two such examples. Exhaustion of natural fishing stocks is another, these have been in serious decline since the 1950s. Nature in 2003 reported a 90% decline in big sea fish since 1950. In 1999 the FAO survey indicated three-quarters of surveyed species stocks were fully exploited or overfished. Extrapolations on current trends carried out by Dalhousie University in late 2006 suggested that virtually all natural ocean fishstocks could be exhausted by 2050.

As of 2006, the major cause of deforestation and desertification include the "slash and burn" agricultural techniques, various timber industries, agriculture and livestock grazing, urban sprawl, and mining. Particular damage has occurred in the the United States where the Great Plains were converted to the Dust Bowl of the 1930s, the expansion of the Taklamakan desert in the Xinjiang region in north-western China, and Nigeria, which has lost more than half its forest in the last five years. One can add to these examples, the highly polluted and salinated remains of the Aral Sea which, due to the diversion of its major rivers for cotton irragation in the 1930s, has now shrunk by 80% in volume and the massive problem of salination of the soil in Australia (especially in the south-west), where some 20,000 square kilometers of thin top-soil have become irreversibly salty.

Predictions, Problems and Perscriptions

In the 1968 book "The Population Bomb" Paul Ehlrich, predicted that "in the 1970s and 1980s hundreds of millions of people will starve to death". Others, such as noted environmental analyst Lester Brown began predicting that population would soon outstrip food production in 1973 and continues to do. The reality is since 1961 world population has doubled, but food production even more so, leading to a 20% increase per head and a 27% increases in calories consumed in the developing world since 1963. So as can be seen, predictions of the environment and consequences are fraught with the difficulty of predicting human action and the regulatory regime, technological change, and the economic effects of substitution, where price increases in a resource stimulate demand for alternatives (a simple example is the search for oil in the 19th century because of the decline of the whale population).

The difficulties of making such predictions do not of course mean that we should simply give up and stop making them of course. In fact, the difficulty should inspire more rigorous research and more exacting standards and a total committment to discovering the truth, especially given the stakes - the future of the the planet's environment. Under this caveat, it is perhaps opportune to condemn certain scientists who engage in what is worse that those historical revisionists who engage in holocaust denial or deny the deaths of the Gulags or the Cultural Revolution. Such reactionaries are not dangerous, but pathetic. Scientists who have accepted and continue to payments from vested interests to promote selective data and engage in wild hypotheses are far worse. The website Sourcewatch provides an excellent list of such scientists who bring such dishonour to their profession and the monies they have received.

By way of a conclusion, in order to reduce the prospect of destructive global warming, to protect finite resources, and to limit pollution can all comes down to adopting economic models where one must pay for the resources used, rather the value of the production undertaken. Under such circumstances, valuable production with low resource costs should be encouraged. The influential mathematical statistician Harold Hotelling established such a model of 'scarity rent' in pricing finite resources as long ago in the 1930s. Carbon credits and personal carbon trading are two other examples whose restraining influence is far greater - and more subtle - than any regulatory regime which merely establishes ceilings of use, or prohibts. These mechanisms recognise the common and equal right that all human beings have with the gifts of Providence, and also the UU Principle of "respect for the interdependent web of existence". Because if that principle was already in application, perhaps the Yangtze River Dolphin would be still with us today.

1] The Baiji Yangtze Dolphin is with all probability extinct, Baihi.Org, 13 December 2006
2] Jones, P.D. and Moberg, A. (2003) "Hemispheric and large-scale surface air temperature variations: An extensive revision and an update to 2001". Journal of Climate, 16, 206-223. Derived Image availabe.
3] Intergovernmental Panel on Climate Change Report 2001, Climate Change Science: An Analysis of Some Key Questions (National Research Council, 2001), Climate Change Research: Issues for the Atmospheric and Related Sciences, (American Metereological Society, 2003)
4] Meehl, G.A., W.M. Washington, C.A. Ammann, J.M. Arblaster, T.M.L. Wigleym and C. Tebaldi (2004). "Combinations of Natural and Anthropogenic Forcings in Twentieth-Century Climate". Journal of Climate 17: 3721-3727. Derived image available
5] IPPC first report was 1990, most recent 2001. Current report is due for publication in February 2007.
6] Bruce C. Douglas (1997). "Global Sea Rise: A Redetermination", Surveys in Geophysics 18: 279-292. and TOPEX/POSEIDON (T/P) satellite mission and the Proudman Oceanographic Laboratory (POL)
7] Dyurgerov, Mark B. and Mark F. Meier (2005). "Glaciers and the Changing Earth System: A 2004 Snapshot". Institute of Arctic and Alpine Research, Occasional Paper 58. Derived image available.
8] Hannah Hoag, "Global Warming Already Causing Extinctions, Scientists Say", National Geographic News, November 28, 2006

Address to the Melbourne Unitarian Church, January 14, 2007