When I worked with wildlife a lot in the Eighties and Nineties, I learnt the meaning of patience. And when I worked with trees, I learned the meaning of humility.

I was raised a Catholic as a boy and went to a Catholic boys' high school, a private school, and kind of drifted away, candidly, in my latter teen years. I consider myself deeply spiritual but not in an institutional, religious kind of a way. In Catholicism, we're surrounded by these images of martyrdom and doing penance and doing some suffering to achieve what you're trying to achieve. And I certainly embedded that in my psyche and I have lived that very effectively.

I personally spend the majority of my time by far on outreach and education and fundraising and administration.

Glacial pace is actually an incorrect concept. The glaciers move a lot faster and they react a lot faster than people imagine.

Ultimately, we have to ask ourselves an essential spiritual and ethical question: Are we the kind of people who take everything for ourselves and leave nothing for others, or do the angels of our better nature still live? I believe the angels are still alive.

I have often thought that my work with wildlife taught me the meaning of patience, and my work with the big trees taught me the meaning of humility, and my work with the ice has taught me the meaning of mortality.

The 'New Yorker' asked me to shoot a story on climate change in 2005, and I wound up going to Iceland to shoot a glacier. The real story wasn't the beautiful white top. It ended up being at the terminus of the glacier where it's dying.