As the UN climate summit in Copenhagen approaches, exhortations that "we must get a deal" and warnings that climate change is "the greatest challenge we face as a species" are to be heard in virtually every political forum.

But if you look back to the latest definitive check on the planet's environmental health - the Global Environment Outlook (Geo-4), published by the UN two years ago - what emerges is a picture of decline that goes way, way beyond climate change.

Species are going extinct at perhaps 1,000 times the normal rate, as key habitats such as forests, wetlands and coral reefs are plundered for human infrastructure.

Aquifers are being drained and fisheries exploited at unsustainable speed. Soils are becoming saline, air quality is a huge cause of illness and premature death; the human population is bigger than our one Earth can currently sustain.

So why, you might ask, are the world's political leaders not lamenting this big picture as loudly and as often as the climate component of it?

Has climate change hijacked the wider environmental agenda? If so, why? And does it matter?

Read more @ BBC News