I thank the government and people of for hosting this international conference. You have warmly welcomed thousands of people into your midst, and created excellent conditions for the crucially important work on our agenda. Thank you for yet another strong show of support for the United Nations.
All of us in this hall are devoted to the betterment of the human condition. All of us want to see a day when everyone, not just a fortunate few, can live in dignity and look to the future with hope. All of us want to create a world of harmony among human beings, and between them and the natural environment on which life depends.
That vision, which has always faced long odds, is now being placed in deeper jeopardy by climate change. Even the gains registered in recent years risk being undone.
Climate change is not just an environmental issue, as too many people still believe. It is an all-encompassing threat.
It is a threat to health, since a warmer world is one in which infectious diseases such as malaria and yellow fever will spread further and faster.
It could imperil the world’s food supply, as rising temperatures and prolonged drought render fertile areas unfit for grazing or crops.
It could endanger the very ground on which nearly half the world’s population live - coastal cities such as Lagos or Cape Town, which face inundation from sea levels rising as a result of melting icecaps and glaciers.
All this and more lies ahead. Billion-dollar weather-related calamities. The destruction of vital ecosystems such as forests and coral reefs. Water supplies disappearing or tainted by saltwater intrusion.
Climate change is also a threat to peace and security. Changing patterns of rainfall, for example, can heighten competition for resources, setting in motion potentially destabilizing tensions and migrations, especially in fragile States or volatile regions. There is evidence that some of this is already occurring; more could well be in the offing.
This is not science fiction. These are plausible scenarios, based on clear and rigorous scientific modelling. A few diehard sceptics continue to deny global warming is taking place and try to sow doubt. They should be seen for what they are: out of step, out of arguments and out of time.
In fact, the scientific consensus is becoming not only more complete, but also more alarming. Many scientists long known for their caution are now saying that global warming trends are perilously close to a point of no return.
A similar shift may also be taking place among economists. Earlier this month, a study by the former chief economist of the World Bank, Sir Nicholas Stern of the , called climate change "the greatest and widest-ranging market failure ever seen." He warned that climate change could shrink the global economy by 20 percent, and cause economic and social disruption on a par with the two World Wars and the Great Depression.
The good news is that there is much we can do in response. We have started using fossil fuels more cleanly and efficiently. Renewable energy is increasingly available at competitive prices. With more research and development - current levels are woefully, dangerously low - we could be much farther along.
Spurred by the Kyoto Protocol, international carbon finance flows to developing countries could reach $100 billion per year. Markets for low-carbon energy products are expected to grow dramatically.
But we need more "green" approaches to meet surging energy demand. And we need to put the right incentives in place to complement the constraint-based efforts that have prevailed to date.
The climate challenge offers real opportunities to advance development and place our societies on a more sustainable path. Low emissions need not mean low growth, or stifling a country’s development aspirations.
So let there be no more denial. Let no one say we cannot afford to act. It is increasingly clear that it will cost far less to cut emissions now than to deal with the consequences later.
And let there be no more talk of waiting until we know more. We know already that an economy based on high emissions is an uncontrolled experiment on the global climate.
But even as we seek to cut emissions, we must at the same time do far more to adapt to global warming and its effects. The impact of climate change will fall disproportionately on the world’s poorest countries, many of them here in Africa . Poor people already live on the front lines of pollution, disaster and the degradation of resources and land. Their livelihoods and sustenance depend directly on agriculture, forestry and fisheries.
Think, for example, of the women and girls forced to forage for fuel and water in the absence of basic energy services. Or of the innumerable African communities that have suffered climate-related disasters in recent years. The floods of , the droughts in the Sahel and here in , are fresh in our memories. For them, adaptation is a matter of sheer survival. We must make it a higher priority to integrate the risks posed by climate change into strategies and programs aimed at achieving the Millennium Development Goals.
The message is clear. Global climate change must take its place alongside those threats - conflict, poverty, the proliferation of deadly weapons - that have traditionally monopolized first-order political attention. And the United Nations offers the tools the world needs to respond.
Regional and national initiatives have their value. But the UN Framework Convention is the forum in which a truly global response is being formulated.
The Kyoto Protocol is now fully operational, and its Clean Development Mechanism has become a multibillion-dollar source of funding for sustainable development.
This mechanism is an outstanding example of a UN-led partnership linking government action to the private sector in the developing world.
I am pleased to announce that six UN agencies have launched, at this conference, the "Nairobi Framework," a plan to support developing countries, especially in Africa , to participate in the Clean Development Mechanism. I encourage donor countries to help make these efforts a success.
I am also pleased to note that today, UNDP and UNEP are embarking on an initiative to help developing countries, again including in Africa, to factor climate change into national development plans - so-called "climate proofing" in areas such as infrastructure.
UN agencies will continue to bring their expertise to bear. But the primary responsibility for action rests with individual atates - and for now, that means those that have been largely responsible for the accumulation of carbon dioxide in the atmosphere. They must do much more to bring their emissions down.
While the Kyoto Protocol is a crucial step forward, that step is far too small. And as we consider how to go further still, there remains a frightening lack of leadership.
In developing countries, meanwhile, emissions cannot continue to grow uncontrolled. Many of them have taken impressive action on climate change. Rapidly growing economies, like , have been increasingly successful in decoupling economic growth from energy use, thereby reducing the emission intensities of their economies. But more needs to be done.
Business, too, can do its part. Changes in corporate behavior, and in the way private investment is directed, will prove at least as significant in winning the climate battle as direct government action.
And individuals too have roles to play. A single energy-efficient light bulb placed in a kitchen socket may not seem like much; but multiplied by millions, the savings are impressive.
Voting power could be similarly compelling, if people were to make action on climate change more of an election issue than it is today and individuals, through their purchasing choices, can put pressure on corporations to go green.
There is still time for all our societies to change course. Instead of being economically defensive, let us start being more politically courageous.
The Nairobi Conference must send a clear, credible signal that the world’s political leaders take climate change seriously.
The question is not whether climate change is happening or not, but whether, in the face of this emergency, we ourselves can change fast enough.