Addiction is a terrible thing. It consumes and controls us, makes us deny important truths and blinds us to the consequences of our actions. Our world is in the grip of a dangerous carbon habit.

Coal and oil paved the way for the developed world’s industrial progress. Fast-developing countries are now taking the same path in search of equal living standards. Meanwhile, in the least developed countries, even less sustainable energy sources, such as charcoal, remain the only available option for the poor.

Our dependence on carbon-based energy has caused a significant build-up of greenhouse gases in the atmosphere. Last year, the Nobel Peace Prize-winning Intergovernmental Panel on Climate Change put the final nail in the coffin of global warming sceptics. We know that climate change is happening, and we know that carbon dioxide and other greenhouse gases that we emit are the cause.

We don’t just burn carbon in the form of fossil fuels. Throughout the tropics, valuable forests are being felled for timber and making paper, for pasture and arable land and, increasingly, for plantations to supply a growing demand for biofuels. This further manifestation of our carbon habit not only releases vast amounts of CO_2; it also destroys a valuable resource for absorbing atmospheric carbon, further contributing to climate change.

The environmental, economic and political implications of global warming are profound. Ecosystems -- from mountain to ocean, from the Poles to the tropics -- are undergoing rapid change. Low-lying cities face inundation, fertile lands are turning to desert, and weather patterns are becoming ever more unpredictable.

The cost will be borne by all. The poor will be hardest hit by weather-related disasters and by soaring price inflation for staple foods, but even the richest nations face the prospect of economic recession and a world in conflict over diminishing resources. Mitigating climate change, eradicating poverty and promoting economic and political stability all demand the same solution: we must kick the carbon habit. This is the theme for World Environment Day 2008. “Kick the Habit: Towards a Low Carbon Economy”, recognizes the damaging extent of our addiction, and it shows the way forward.

Often we need a crisis to wake us to reality. With the climate crisis upon us, businesses and governments are realizing that, far from costing the Earth, addressing global warming can actually save money and invigorate economies.  While the estimated costs of climate change are incalculable, the price tag for fighting it may be less than any of us may have thought.  Some estimates put the cost at less than one per cent of global gross domestic product -- a cheap price indeed for waging a global war.

Even better news is that technologies already exist or are under development to make our consumption of carbon-based fuels cleaner and more efficient and to harness the renewable power of sun, wind and waves. The private sector, in particular, is competing to capitalize on what they recognize as a massive business opportunity.

Around the world, nations, cities, organizations and businesses are looking afresh at green options. At the United Nations, I have instructed that the plan for renovating our New York headquarters should follows strict environmental guidelines. I have also asked the chief executives of all UN programmes, funds and specialized agencies to move swiftly towards carbon neutrality.

Earlier this year, the UN Environment Programme launched a climate neutral network -- CN Net -- to energize this growing trend.  Its inaugural members, which include countries, cities and companies, are pioneers in a movement that I believe will increasingly define environmental, economic and political discourse and decision making over the coming decades.

The message of World Environment Day 2008 is that we are all part of the solution. Whether you are an individual, an organization, a business or a government, there are many steps you can take to reduce your carbon footprint. It is message we all must take to heart.