All seems a bit hard....maybe I'll wait and see if its really within our control first.

Anybody who thinks that total world global warming emissions can be reduced without doing anything about the burgeoning population in the third world is urinating into the breeze.

The issue of population growth is revisited, but I worry that it is mentioned or considered on the assumption by some that population growth is a necessary first step.

One of the first futures modeling efforts, the Club of Rome's "Limits to Growth", made clear 35 years ago that at least five major variables are interlinked in global ecological problems.

Changing their pattern of interaction must be part of the solution to global warming.

The Wikipedia entry on The Club of Rome names the five variables as "world population, industrialization, pollution, food production and resource depletion." The Club of Rome has continued its modeling work and has addressed many of the shortcomings which were noted after "Limits to Growth" gained widespread publicity.

World population is the most loosely linked of the five variables. It has already been radically addressed by the Chinese. That will not stop the Chinese from increasing their outputs of CO2 and other industrial pollutants, if they continue their present pattern of industrial growth.

And as with the Chinese, so it is with the rest of us. Zero population growth does not assure zero greenhouse gas increase.

Well, wasn't that a lot of hot air. A few suggestions as to some solutions might have been appropriate, I would have thought. Why is it that the people who respond to these writings are the one who generally propose the solutions to the problems?

Don't knock the ZPG proposition, although I would have to go further than that. It is about time we got rid of the current Federal Treasurer who still wants population growth. I have just flown over about five hundred kilometres of virtually bare dirt across half of Victoria and New South Wales and it looks like we will be struggling to feed the current population if the present rainfall pattern continues.

When you save water, the water utilities up the price... same will happen with greenhouse emmissions.....

Mary, I want to see hydrogen cars racing at Bathurst, I'd love to save money by putting a wind turbine and solar panels on my roof. But how can I afford these unless government or business show me how to make them (yeah right) assist.

What we don't need are 5 billion separate efforts. What's needed is leadership and coordination, and not corporate profiteering.

Forgive me, but I'm a bit more concerned about the human beings suffering from malnutrition (I don't think there's any controversy over whether or not this is real) than some vague impact I can have on the environment.

Re: lower populations, if we could just bring health and education to the third world, it would drastically change things. Families tend to have less children as women get better educated.