"The greatest threat to our planet is the belief that someone else will save it." Robert Swan, OBE, Explorer and Environmentalist
Contact: email email@example.com
IntroductionEarth is the only planet we have. There has long been talk of the colonization of other planets, but if that is ever going to be possible it is many decades away. Consider for a minute; Mars is the solar-system planet with the most Earth-like environment, yet it is much more hostile than Antarctica or the driest desert on Earth – probably Mars is more hostile to human life than the sea-beds on the shallower parts of the continental shelves; if the collonisation of Mars is possible, why have we not colonised these areas?
There may be more hospitable planets near other stars, but moving large numbers of people and large loads of materials over that sort of distance is beyond our abilities for the foreseeable future.
Almost all my Internet pages relate in one way or another to either ethics or the environment (and the two are closely linked, a society cannot be ethical without protecting its environment for future generations). Why have I written this page? I'm not at all sure; it is certainly not a summary of all else.
The earth's easily and cheaply accessed petroleum supply has largely been
used up; the remaining reserves are beneath the deep oceans, in the arctic, or
in tar sands, coal seams, or oil shales.
Accessing these comes with huge environmental risks and often even greater
greenhouse penalties than conventional oil.
The graph on the right, from the Australian Commonwealth Scientific and Industrial Research Organization (CSIRO), shows the rise in atmospheric CFCs, then the beginning of the fall.
As a civilization we are destroying our forests, causing the greatest rate of extinctions for many millions of years, causing salinisation and desertification of farmland at very high rates, mining all the easily accessible minerals with no consideration for those who will come after us, and polluting our air, water and soils.
It is true that it would be very expensive to change to a way of life that is completely sustainable. It is also true that we could go a long way toward that goal without much effort at all. But our leaders are too busy sacrificing all that is valuable on Earth to Mammon to adopt a precautionary approach.
To a large extent it is not so much people who are running the world, it is the capitalist system, which seems to react amorally to any opportunity that can turn a profit. It is up to us to reign it in and turn our use of the biosphere to one that is sustainable. Moneyed interests dominate our governments; they will not change unless they are forced to. The great majority of people can see the damage that is being done, but they are either too apathetic or too shortsighted to try to stop it. Three quotes are appropriate here:
has an extensive article on the subject.
Rising atmospheric carbon dioxide (CO2), primarily from human fossil fuel combustion, reduces ocean pH and causes wholesale shifts in seawater carbonate chemistry. The process of ocean acidification is well documented in field data, and the rate will accelerate over this century unless future CO2 emissions are curbed dramatically. Acidification alters seawater chemical speciation and biogeochemical cycles of many elements and compounds. One well-known effect is the lowering of calcium carbonate saturation states, which impacts shell-forming marine organisms from plankton to benthic molluscs, echinoderms, and corals. Many calcifying species exhibit reduced calcification and growth rates in laboratory experiments under high-CO2 conditions.On 2012/10/08 Google Scholar recorded 503 citations to this paper.
More on ocean acidificationKen Caldeira and Michael E. Wickett published a paper titled 'Anthropogenic carbon and ocean pH' in the prestigeous science journal Nature, Volume 425, 2003/09/25. They stated "The coming centuries may see more ocean acidification than the past 300 million years".
Extracted from Environmental Science and Technology online:
"Average oceanic pH has decreased from a pre-industrial level of 8.16 to 8.04 today (Science 2004, 305, 362-366; 367-371). If the CO2 concentration doubles from present levels by 2100, as some models predict, then the pH could drop to a level between 7.6 and 7.8."
Ocean acidification will have an adverse effect on marine organisms. In particular it increases the solubility of the calcium carbonate that makes up the shells of many marine animals; making it harder for them to build their shells. Corals, whose skeletons are calcium carbonate, may be adversely effected by acidification as well as by the global warming that leads to coral bleaching.
LinksThere are a huge number of scientific paper dealing with ocean acidification, far too many for me to cite here, see Google Scholar or Google Scholar, Australia.
Ivan Nagelkerken, Associate Professor, Marine Biology, University of Adelaide, wrote a piece titled "The oceans are changing too fast for marine life to keep up" on The Conversation, 2015/10/13.
Recently a friend told me that she rides her bike to work most days; by bicycle she takes 30 minutes against 45 by car. Then I read a suggestion by the Government's ideas man (Herbert Girardet) suggesting that Adelaide could be greatly improved if there was more pedestrianisation (sic) and a lot more cycling.
It struck me how much Adelaide would change for the better if most of the commuters either rode bikes or walked to work.
Perhaps I'm dreaming, or perhaps it could happen?
I should first discuss a question to which the answer will seem obvious to many readers:
Is the world overpopulated?If there were far fewer people in the world then there would be no need for starvation or malnutrition. We could all make a living by subsistence farming if no other course was available to us. In fact, there is no unused land for those who are malnourished to set up subsistence farms.
A hundred people defecating in a large river would be insufficient to cause that river to become polluted; the other life forms, bacteria, fish, invertebrates, etc., would keep the human-introduced toxins and harmful micro-organisms to levels that are harmless. If the sewage of a million people is dumped into a large river it will overload the ability of the river to clean itself.
Many of the Earth's rivers are polluted with sewage. Production of pollutants is, everything else being equal, proportional to population. If there were 600 million people on the Earth rather than six billion, and living standards were the same as today's, greenhouse gas production would be little problem.
If there were insufficient people in the world then people would be valuable. In 1850 an agricultural slave cost $30 000 (today's dollars) in Alabama, but today an equivalent slave laborer can be had for around $100. (Scientific American, April 2002.) World-wide there are millions of refugees who have to live in camps because no nations want them.
If there were one tenth as many people on the Earth then farmers would be able to farm only the best land; the marginal land could be left for nature. If there were only one tenth as many people we would not be facing the loss of most of the world's forests within a few decades, and we would not be nearing the end of petroleum reserves.
In most nations people are permitted to have as many children as they choose. (Not all, Singapore provides strong disincentives for large families.) It seems generally accepted that there is an unwritten right to produce any number of children. This was acceptable when there was a perceived need for more people, but it should have been abolished long before now.
It seems to me that, ideally, the whole world should follow the Chinese example of one child per family until world population falls to, perhaps, one billion. This would be a very difficult law to get people to accept, so perhaps a limit of two should be aimed at first.
Several religions encourage the production of large families. This would be a major impediment and it is difficult to imagine how it might be changed in the time we have available to us before overpopulation brings about a disaster. (I have discussed religion under Ramblings on false beliefs.)
I would hold that no more than 10 million is the maximum desirable population level. Why?
Oil and gas peak production of oil is expected to come in the near
future. When world oil yields start to decline gas yields will not be
far behind. In general Australia relies very heavily on the unsustainable
burning of fossil fuels for its energy.
What are the sustainable alternatives?
Nuclear fission could be a partial medium-term (100 years) solution, but it comes with risks, is not likely to be politically acceptable in Australia in the foreseeable future, and is of no use for powering transport at the present state of technology.
Nuclear fusion may become feasible in the future and if so could become a medium-long-term solution, however, it is not yet available.
Wind/hydro/biomass Wind does not blow all the time; while hydro and biomass can be used to generate electricity sustainably they would not be sufficient for Australia's current population, but may be sufficient for a considerably reduced population.
The forms of agriculture currently practiced in Australia are unsustainable
for several reasons. Reducing the nation's population could proportionally
reduce the problems mentioned below.
Large energy inputs required Not so much for tilling the land but for production of, in particular, the high level of nitrogenous fertilizer required; also for production of agricultural chemicals.
Phosphate cycle At present in Western agriculture phosphate is mined, processed, and applied to the land. It is then, in a fairly short time either removed from the land with the agricultural produce, or is leached from the soil; either way it is not returned to the soil. The end of this system comes when the readily accessible phosphate rocks are mined out, and this time might not be far off.
Pollution from excess nutrients Modern agricultural practices result in some of the nitrates and phosphates applied to the land being washed into waterways and causing problems such as toxic algal blooms and changing ecological balances.
Currently, as mentioned above, fossil fuels are the primary source of our
energy and this is plainly unsustainable. Wood fires are a practicable
alternative for home heating, however, smoke is a problem in some urban
areas. Perhaps the real problem is that urban population densities have
become too great; smoke from fires
is, after all, a very natural part of the Australian environment. A lower
Australian population level could be the answer.
A similar argument applies for several other forms of pollution.
|Biodiversity||Australia's biodiversity has declined since Man came and especially quickely since white settlement. If our population was reduced we could put more land asside to try to stop the loss of species.|
|A simple solar water heater at Elysium.|
Burning firewood is not the only environmentally friendly way to heat water. In Australia in the warmer three-quarters of the year solar water-heating, using commercially available heaters, is quite practical. I have used one at my home at Crystal Brook for 25 years. Several times the cost of the heater must have been saved on electricity bills over this time, not to mention the reduction in greenhouse gas production.
A simple solar water-heater can be made by laying out about 30m of 50mm black polythene pipe in a sunny position. I use this method as an alternative to the wood-fired heater at Elysium.
This simple water-heater works best on warm, calm, sunny days. It will
provide water warm enough for a shower on a sunny calm day of
20oC, or on a 28oC
day if there is a breeze. Covering the pipe with glass to stop air
circulation (produce a greenhouse effect!) would improve its efficiency.
Water can circulate by convection on a warm day so that the water in the
tank on the left is heated. The tank is not insulated, but it will stay
warm for several hours after the sun stops shining on the pipe coil.
|Configuration of valves to control flow|
On a 32oC day in December (Southern summer) with a light breeze I measured the temperature of the water in the tank at 50oC just after the sun had passed the zenith.
The second photo shows the valves on solar/wood-fired water heater
It's a bit of a plumber's nightmare, but different configurations of opening and closing the valves allow:
|This is the solar pond at Pyramid Hill|
This method of heating water is not suitable for household hot water. It is a method of producing industrial energy. I believe it may have potential for use in desalination of water in areas such as South Australia's Eyre Peninsula, where potable water is scarce. See Water which particularly deals with Eyre Peninsula.
RMIT University, Geo-Eng Australia Pty Ltd and Pyramid Salt Pty Ltd have
developed a commercial solar pond in north-central Victoria.
Here the heat from the
solar pond is used to dry salt. They have calculated that
northern Victoria can produce process heat (40 - 80 oC)
for a wide range of
applications at an average cost of about between $10 and $15/GJ.
|Solar collector troughs are another way of using solar energy to heat water.|
states that up to 18% of the energy required to make new glass bottles
is saved by
recycling old glass. Other pages on the Net indicate even more energy might
be saved by recycling.
But how much energy would be saved if the bottle was cleaned out and reused rather than melted and re-cast, 95%?
In the developed countries we are encouraged to recycle, and I don't doubt that recycling is better than dumping in a land fill, but how much better again would it be if we reused rather than recycled?
In a World in serious trouble with greenhouse/climate change it is unacceptable to smash a bottle, remelt the glass, and recast a new bottle rather than cleaning out and reusing the old bottle.
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