Successful movements also need an organisational model that allows them to keep growing.

I might find myself standing, transfixed, by the roadside, watching a sparrowhawk hunting among the bushes, astonished that other people could ignore it. But they might just as well be wondering how I could have failed to notice the new V6 Pentastar Sahara that just drove past.

Immense wealth translates automatically into immense environmental impacts, regardless of the intentions of those who possess it.

Places that have become agricultural deserts, trashed by giant corporations, could be reforested, drawing carbon dioxide from the air on a vast scale. The ecosystems of land and sea could recover, not just in pockets but across great tracts of the planet.

America's experience, like many others, teaches us that fostering entrepreneurship is not just about crafting the right economic policy or developing the best educated curricula. It's about creating an entire climate in which innovation and ideas flourish.

Those who deny human-caused climate change offer no compelling evidence to better explain the undeniable rise in atmospheric concentrations of greenhouse gases and global temperature.

Mark Ruffalo, aka the Incredible Hulk, is the natural gas industry's worst nightmare: a serious, committed activist who is determined to use his star power as a superhero in the hottest movie of the moment to draw attention the environmental and public health risks of fracking.

In particular, Australia, because of its ancient geography, soil profile and distinctive weather patterns, is more adversely affected by climate variability than some other continents.