Sir David Attenborough
For 50 years Sir David Attenborough has brought the far reaches of the natural world into the comfort of our own homes.
He's produced 10 major series for the BBC the most recent being Planet Earth.
At the launch of his friend Tim Flannery's new book, The Weather Makers, Sir David shared his thoughts on climate change.
If my grandchildren thought of me when they looked at the desolation that has overcome great patches of the earth and thought, 'He knew what was happening but he did nothing about it', I would feel deeply, deeply ashamed of myself.
Sir David on the futurePopulation growth and climate change
The fact that over twice as many people inhabit the Earth as when I was born draws you short. The planet cannot sustain an infinitely growing population.
I saw some graphs that plotted CO2 in the atmosphere over the past thousand years. Plotted against that was human population over time.
Superimposed over one another, they were almost identical. Humanity has changed the climate.
A colleague of mine back from the Antarctic reported that grass is now growing on the Antarctic continent.
Sir David AttenboroughHow else do humans affect nature?
My job is to film nature in the wild, where it flourishes. Remote places have become more and more difficult to find.
I find myself going back to places and being horrified by what I see. I remember the richest rainforest in Borneo - it had been cut down to make a plantation of oil palm.
The plantation was abandoned because the soil on which that forest flourished was poor and could not support oil palm trees. There was eroded clay, a wasteland, a sterile, empty wasteland.Waste not, want not?
During World War II there was a morality about waste - it was sinful to be wasteful. So this is a moral question.
It shapes how we conduct our lives, how we look at energy and how we look at waste.
We can have no doubt the world is warming. Our job is to protect the marvellous world which we are part of, right now.
Sir David on climate changeIs wind part of the solution?
All power has a price. Science has an obligation to generate power which has the minimum price.
We know that wind has less of a price to pay. To dismiss wind generation simply on the grounds that it spoils the view, does not appreciate the scale of the problem.What can we do?
Small things might seem trivial: Turn off that light. Don't book that expensive aircraft seat when you could go by rail. Switch off the standby on your television set.
The most powerful changes of human behaviour come from change in the attitudes of what we think is moral.
It's about people not saying 'What a wonderful, powerful car' but instead thinking - 'That car's squandering precious resources .and that's something I wouldn't do'.