When I was at drama school, I wanted to change the world, and thought I had some great wisdom to impart to people about humanity. Now that I'm older, I know enough to realise that I know nothing at all.

Doing all we can to combat climate change comes with numerous benefits, from reducing pollution and associated health care costs to strengthening and diversifying the economy by shifting to renewable energy, among other measures.

From year to year, environmental changes are incremental and often barely register in our lives, but from evolutionary or geological perspectives, what is happening is explosive change.

People can undergo a sudden change of thinking and loyalties under threat of death or intense social pressure and isolation from friends and family.

Some people call it global warming some people call it climate change. What is the difference?