Sustainable development: 'The planet is at a crucial crossroads'

A recent UN programme says sustainability is not only natural but essential. Fred Pearce looks at its chances

A tide of tarmac is spreading over the planet. Around half of the land surface of the Earth is carved up by human activity. Cities and farms, roads and mines, pipelines and pylons have either covered or hopelessly fragmented 50 per cent of the world's natural vegetation.

Nowhere is safe. Not the rainforests of the Amazon, not the frozen but oil-rich wastes of Siberia, not the deserts of Arabia. If the world's economy continues in its current breakneck manner, then within three decades, 70 per cent of the land will be destroyed, fragmented or disturbed by human activity.

Yet, according to the UN Environment Programme (UNEP), a switch to a more environmentally friendly approach to economic development could stop most further destruction – and even allow nature to return to areas of Europe and North America where population growth has more or less ceased. And all without damaging economic growth.

In a study prepared for the World Summit, more than a thousand scientists, recruited by UNEP, outlined two possible approaches to future growth: one based on untrammelled "markets first" and a second that put "sustainability first".

Both brought real economic growth at a similar speed. But while the markets-first approach trashed the environment, sustainability-first protected the planet from most of the worst damage. It also appeared to offer the best chance of long-term wealth and social harmony. "The planet is at a crucial crossroads, with the choices made today critical for the forests, oceans, rivers, mountains, wildlife and other life-support systems upon which current and future generations depend," says UNEP director Klaus Töpfer.

If markets and free trade remain the sole criterion for economic planning, the UNEP scientists predict that global warming will continue to accelerate, with emissions of the chief greenhouse gas carbon dioxide more than doubling by 2030.

The scientists predict that within three decades, 85 per cent of Latin America will be carved up by development – the highest figure for any continent. The region is already home to four of the top 10 megacities and continued urban growth would be a death knell for the Amazon rainforest. Meanwhile, a rash of mines and hydropower plants would be in operation across the Arctic, where global warming will open shipping lanes to even the most remote land areas.

But the sustainable option would see rainforests and Arctic wastes protected in a world where more and more people live frugal, train-riding, telecommuting lives. Cities would be compact, highways subdued, many mines replaced by recycling plants and power stations by neighbourhood renewable-energy centres. In Europe, the report foresees outer suburbs emptying, roads closing and forests and wetlands being recreated.

Old North Sea oil platforms would sprout wind turbines and the Nevada desert would be covered in solar panels. Iceland would be dubbed the "green Kuwait" – the first country to run without fossil fuels, exporting clean hydrogen fuel generated from its glaciers and volcanic geysers.

Can this transformation to sustainability happen? Well, some progress is already being made. City air in North America and Europe is substantially cleaner than a generation ago. Cleanup technology has more than kept pace with rising economic activity and car use. Acid rain is in full-scale retreat. Even China, the new world industrial powerhouse with 10 per cent annual economic growth, is banishing its smogs and is cutting greenhouse gas emissions.

Every year, we produce our economic goods from fewer natural resources and with less pollution. Such trends are natural. Pollution is waste and economic efficiency should arise from environmental efficiency. But sustainability is not only natural, it is also essential, says UNEP.

Global warming is starting to cause climatic havoc. This year is just the latest when floods, hurricanes, droughts and other freak weather conditions have caused widespread deaths and sent insurance claims soaring. The number of people affected by climate-related natural disasters rose 50 per cent during the Nineties and financial loss from such disasters now regularly top $100bn (£65bn) a year. One insurance industry projection of current trends puts the cost of climate disasters at more than global GDP by 2060.

Even leaving aside global warming, the UNEP scientists concluded that environmental degradation is damaging economic growth. India is already losing $10bn (£6.5bn) a year – almost 5 per cent of its GDP – from air pollution, soil erosion and the destruction of nature. The "brown haze" reported across southern Asia this summer could be cutting Indian rice yields by as much as 10 per cent.

Sustainability means just that, says UNEP. If we want to sustain economic growth over the long term, we have no choice but to factor in the environment and our natural resources.