I will ride a bike rather than drive the car if it is practical, and we stockpile soft plastic in the hope that one day, preferably soon, we will be able to recycle that. We try to be vegan but in reality we are merely vegetarians. I don't think our actions alone will save the planet but one does what one can.

But does one? There are many measures of wealth and many measures of a person's carbon footprint but overall it seems that a very wealthy person will have a footpint about ten times greater than that of a normal person.

I have known someone whose boat cost $8,000 to fill with diesel, and that was a few years ago. I'm not sure how long that would last but it seems like a lot of fuel to burn in a pleasure boat. I wonder how far someone would have to ride a bicycle to offset that lot. And what about people who fly around in private jets?

A study at the University of Bern in Switzerland concluded that a person's carbon footprint is better indicated by their income than their environmental beliefs. All of which raises the questions: Why should I bother? lf I don't bother why should you? If you don't bother why should the next person? And so it goes on.

Globally, New Zealand accounts for less than 2% of greenhouse gas emissions, so we as a nation might well pat ourselves on the back and say we hardly contibute to the problem at all. That view would miss the point entirely though. In fact, amongst the OECD we have the fifth highest per capita emissions.

Of course it's tempting to say that rich people should make more effort to be environmentally responsible because they can, proportionally, make more of a difference. They can also afford to make environmentally responsible choices that might be out of the financial range of others; for example by buying electric cars, locally grown organic produce, and solar panels. Somebody who flies four times a year could choose to fly twice a year - that's more of a reduction than many people could make. The irony is that the poor people of the world will suffer the effects of environmental collapse earlier and more severely than the wealthy.

In my view the answer is still that one should do what one can, and I don't mean just recycling or eating less meat, although that's a good start. We should live as though we mean what we say when we talk about being worried about the future of the planet. We should fly less, we should buy local, we should encourage our children to think about solutions. Some of the most amazing technological and societal advances in the field of environmental science and awareness have come from surprisingly young people. If enough ones do what they can there might be enough of a difference made.