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Much environmentalism appears to be a reactionary desire to prevent change - i.e. let's preserve everything in amber now and make sure it stays that way. This is impossible and it is futile to try, but the call for it does tend to illustrate the gross scientific illiteracy of many environmental activists, which wuold be funny were it not so serious.

Earth has indeed changed, and is changing, and will change again in the future, due to factors far more powerful than anything we can do. In the past, global temperatures have variously very much higher than today and very much lower than today, all of which had absolutely nothing to do with man - who didn't even exist at the time. Yet life persists.

It is hubristic arrogance to assume that humanity is so powerful and so important that he can change things like this. He cannot. All that man can do pales into insignificance compared to massive volcanism, asteroid impacts, fluctuations in solar output, and so on. We simply are not that important nor that powerful.

I'd like to see fewer calls for everything to be preserved as it is. Nature will not in any case permit such a thing, so why are those "in touch" with nature advocating it? Let's not waste our time and efforts on such futility.

So what's your solution, Steve? Reduce everyone to poverty and launch a programme of mass murder to reduce the population?

Would it not perhaps be better to consider how we can mitigate the problems by, for example, improving technology to make energy use more efficient, increasing the material wealth of the developing world because increased material prosperity results always in reduced population growth, and even perhaps exploring settlements off this planet?

Or is that not approved because it does not need large scale social regimentation and rationing?

Again, what's your solution? It's not enough to complain, you need to come up with a postive set of actions.

Should we murder large segments of humanity because they have larger economic footprints than fluffy bunny rabbits? Make everyone poor so we can all live in a pre-civilised socialist Nirvana in the pristine woods and caves?

Ecological systems change. Always. Nothing is static, and as change happens so some species will go to extinction, others will thrive, and new ones will evolve. All this happens continually on a scale so vast humanity has difficulty appreciating it, but it happens nevertheless and it will happen with or without humanity existing. What exactly is the problem with this, and what is you solution to it?

I don't see how they would - increasing energy efficiency, slowing population growth and looking at off-planet settlement would *increase* ecological impact? How?

And I'm still waiting for your set of actions. What do you propose? I had a look at your website, and I suspect your favoured answer is a small population (and just how do you achieve this?) living a somewhat backward life through Utopian simplicity. That's all very well, although it's worth pointing out that it is the capitalist system and the highly developed society in which you live - and about which you seem so unhappy - that permits you to make such a choice. Having everyone living like that would wreak far more havoc on the environment than our current system, and really would be unsustainable.

Ed,

Nobody wants a slanging match, merely some concrete proposals beyond complaining about the current situation.

Per capita energy use is also important in relation to the overall efficiency of the energy process. Using more nuclear generated electricity in lieu of gas, oil, coal or electrcity generated therefrom raises the efficiency of the process, permits society to develop by using more energy in absolute but not per capita terms, and at the same time reduces the environmental footprint of that energy use.

You must consider the consumption of energy involved in moving people and goods, of course, but you must also consider the energy use in producing those same goods in the local environment, which may not be suitable for their production - it can require more energy to prodice goods locally than to import by sea or air. You may also wish to visit places in the Third World where much of the economy is of the localised nature you advocate - it is not pretty and it is extremely destructive and inefficient.

Population reduction will come naturally as material prosperity and average life expectancy increase and as infant mortality reduces. This is because people no longer depend to such an extent of their children to support them, and because proportionately more children survive, both of which reduce the need for larger families and thus slow population growth entirely naturally. If you want to see how not to do it, consider the demographic problems of China and India, where your sort of intervention causes all manner of long term problems. Contrast this with the west, where it has happened naturally.

Finally, I think you fall into the Malthusian error of assuming no technological progress and a purely linear relationship between population growth and resource usage. Malthus was wrong, and so I submit are you and those environmentalists who make the same assumptions.

You cannot turn the clock back, basically.

Don,

I don't think there's much doubt that the world is warming. However, there is contention over whether or not humanity has much or anything to do with it. Larger trends utterly beyond man's control are major contributors.

Better to assume it is warming and develop the necessary technologies to cope with it.

To put energy consumption into proportion, it is perhaps worth noting that the Mount St. Helens eruption in 1980 released an amount of energy equivalent to 250 times the entire power generation capacity of the United States.

The Krakatoa explosion in 1883 was some TWENTY times the size.

So, which is more influential - the nasty, evil Americans or Mother Nature?

Examples of falling resource use? Sure:

Coal consumption, together with its emission of greenhouse gas and its horrendous health and environmental burden, has reduced markedly as technological progress has enabled more efficient energy use such as oil, gas and nuclear.

Deforestation has reduced in places where advances in technology mean than the consumption of wood for fuel and construction is no longer necessary (but note how it increases in areas with lower technological progress and expanding population, such as much of the Third World).

Phosphate mining has markedly reduced as synthetic fertilisers have become available. Energy use in transport has decreased per tonne-kilometre as more efficient electric trains, efficient trucks, etc., have replaced older wasteful technology.

Energy use in the production of a great many things has reduced per item produced as technology gets more efficient. The link you posted results in a 403 error, but I note on your website a link to a glass-blowing demonstration. I invite you to consider how much energy would be consumed per tonne of glass blown the old way compared to the modern industrial production of glass.

The first law of thermodynamics shows what would be the minimum energy consumption to make a given product. However, different production processes have different efficiencies, so this does not mean that making a tonne of glass bottles the old way requires the same energy as making the same tonne of bottles the modern way.

Yes, such energy usage is possible because of improved efficiency in usage.

Suppose you have an old power station producing 100MW supporting a population of 100,000. Suppose you replace this with a 120MW plant supporting your growing town population of 150,000 people, who now need less per capita energy because they have insulated their houses and use more efficient appliances. Absolute energy consumption has increased by 20%, but per capita consumption has fallen by 20%.

Over the life of a powerplant, it probably would experience substantial population growth.

I don't think people are worried about China and India wanting the lifestyle we have so much as they are worried about the stages they'll go through to get there and their current inefficient use of energy.

If China and India are allowed to expand their nuclear power programmes - and note that China is at the forefront of developing new pebble-bed reactors - then they will very quickly become much cleaner and more efficient places with higher living standards. If they are required to stay where they are, they will continue their destructive use of fossil and wood fuels, to the detriment of everyone.

With well over a third of the human population between them, are YOU going to tell them that they are not allowed to progress, that they must go backwards? And what do you think their response is likely to be? And why are they wrong to disagree with you?

I think what you may be missing is that the type of society you seem to think is benign and with a small footprint is actually extremely destructive. It is simply that the destruction isn't usually that obvious, especially when it is among a light population in a rural area. It is utterly unsustainable for the global population, and indeed it is only our more advanced & developed society that actually permits such population growth and which will, in its turn, limit this same population growth.

No, Ed, we are not all going to have to make do with less. The question of energy consumption is only one side of the coin, the other being *how* that energy is produced.

If all we could do was burn coal and wood, then you'd probably be right. But we don't need to do that. We can produce electricity from nuclear plants far more cleanly than from any other source, even including wind and even allowing for waste disposal. Quite possibly you don't know this, and more probably do not actually want to to know it, but it is nevertheless true. Denial doesn't alter fact.

Once we have that energy, we can use it much more efficiently than we do now, and we can use more energy for a much smaller impact. We can electrify the railways, we can develop electric mass transit in urban areas, we can develop longer range electric vehicles, we can use nuclear generated electricity or heat to desalinate seawater, thus solving any conceivable drinking water problem, and we can electrolyse the leftover brine to produce hydrogen fuel for mobile transport.

Looking further ahead, we can - and probably will be forced to - produce food synthetically and hydroponically, which is more efficient than any natural process. This doesn't need huge farms, and it can be done basically anywhere you have power, thus eliminating the pressure on arable land and easing the ecological stress of farming. Further ahead still, there is the possiblity of geothermal and fusion power, although these need advances in materials technology.

You don't need to avail yourself of this, and if you wish to turn your back on modern society and live a simpler life, then that's your right and I genuinely hope it works for you. But you don't have the right to foist that view on everyone else, nor to demand that they may not progress just because you don't want to.

Of course the resources for nuclear power are finite - everything is. However, there are a couple of points you overlook:

Known readily exploitable reserves of uranium are sufficient for 50 years at current usage rates. Over one third of these are located in Australia, strategically safer than relying on Middle East or African oil. There's no impetus to search for more right now, because the market isn't there. In the good old capitalist fashion, increased demand, and hence increased price, will stimulate increased search for more deposits - and uranium isn't that uncommon a material, so more deposits will certainly be found. Furthermore, breeder reactors can produce plutonium, which further extends the fuel supply. And even if we get to the end of all that, do you assume we will not have developed something else?

Of course energy ends up as heat. This is not the issue. The putative problem of global warming is not heat release as such - a single big volcano can release far more thermal energy than we can, and don't forget the heat released by all other life on the planet - but rather the reflection of radiated heat back to Earth. Reducing this greenhouse effect reduces the amount of reflection, thus increases radiation loss to the cosmos, and thus basically this is no issue whatever.

As to efficiency gains, I think you probably don't quite appreciate just how significant these can be. For example, a battery-electric car using oil generated electricity is twice the overall oil-well-to-wheel thermal efficiency of a petrol car. Using nuclear generated electricity, the gain is more, because mine-to-plug thermal efficiency of nuclear power is greater than oil. Even that modern petrol car is hugely more efficient than it was even a couple of decades ago, thanks to advanced enegine management and design techniques. Solid state electronics, semiconductor lighting, cheap thermal insulation, more advanced industrial processes - these all make massive efficiency savings.

I'm not Utopian, but equally I am not a pessimistic Malthusian technophobe scared of change and the future.

Here are some energy numbers that put man's effect on the environment into perspective. Feel free to check my back of the envelope calculations.

British installed power generation capacity is around 60GWe (gigawatt-equivalent). Running at around 75% loading, this produces overall some 400TWh (terawatt-hours) of energy each year.

Mount St Helens volcano released some 1.7x10^18 Joules of thermal energy, some 60% of this over the 9 hour blast period. This is equivalent to just over 30 terawatts, 500 times UK installed capacity. If we assume that all Britain's power plants run at 35% thermal efficiency and dump all the lost energy as heat to the atmosphere, then this means that Mount St Helens released in 9 hours the amount of waste heat the entire UK power generation system would lose in thirteen months.

So just how significant is man's energy footprint on the world, do you think?

Ed, if you think that volcanic eruptions are irrelevant in terms of heat input to "the system," then I'm afraid you need to look into things a little more deeply. The amount of heat energy in the "core reservoir" - i.e. already in the system - is unimaginably vast compared to absolutely anything humanity could ever do over any time scale.

For that matter, the amount of heat generated by the fission of uranium in a nuclear reactor is already in the system since it will fission naturally and thus release exactly the same amount of heat. What, therefore, is the problem? As far as heat is concerned in your view of things, we should be going all nuclear immediately since we aren't adding any heat that isn't already there.

On car efficiency, the calculations are simple and not only have I done them before but you can find them done by others on the web. Grid transmission of power is somewhat more efficient than you seem to think, and much more efficient than refining and transporting oil. The battery/electric motor combination in the car is some three times the efficiency of the petrol engine/transmission system in a conventional car. I'll do the calculations again and post them on my blog at some point, but the upshot is that the overall thermal efficiecy is something like 10% for petrol versus about 20% for electric cars. They aren't at all similar and your understanding appears somewhat inaccurate.

Clearly you missed the point about increased demand for uranium fuelling price increases and hence greater exploration efforts. Uranium isn't scarce.