Twenty years ago a landmark study of the world's environment highlighted how human activity is making it more unsustainable. The Brundtland Commission's Our Common Futurewarned that only a short time remained to take effective action against global warming, growing species destruction and degradation of natural resources.
A follow-up study from the UN Environment Programme has underlined that these dangers are more than ever pressing. While public awareness has been transformed - especially on climate change - action taken to stem it is aptly described as "woefully inadequate".
Global warming is the world's central environmental question, but by no means the only one. Fishing capacity is nearly four times more than is sustainable. Species are dying out 100 times more than fossil records show and 12 per cent of birds, 23 per cent of mammals and over 30 per cent of amphibians face extinction. Some 60 per cent of the world's ecosystems have been degraded by over-exploitation and are still being used unsustainably.
The report is harsh about progress made since 1987, but it is convinced there are grounds for optimism. It notes progress made on combating ozone pollution, agreeing the Kyoto protocols on carbon emissions, and setting up protected zones. Rates of deforestation, expansion of crop land and water use are slowing. This can give humanity a chance to cope with and adapt to change. We now know it is much cheaper to act sooner rather than later. Human ingenuity and technological innovation can rise to the challenges posed; we already have the knowledge needed to tackle water pollution, species extinction and systematic over-fishing. But we cannot wait for new technologies to replace fossil fuels and must find complementary ways to reverse these trends.
This, then, is a timely document. It has been published just ahead of the fourth and final report from the International Panel on Climate Change. This will synopsise the extraordinary scientific endeavour that has brought global warming to the centre of international attention this year. Drawing on an unprecedented consensus of scientific research it has put the time for doubt about its damaging impact behind us. The IPCC report will summarise what can be done and indicate how political means can be found to take the necessary action.
A major problem with such environmental warnings is that if they are too apocalyptic or catastrophic they discourage effective action by creating a psychological mood of fatalistic pessimism. This report's qualified optimism about the possibility of change is an encouraging antidote to any such lazy inertia.