09/23/2014 12:55 pm ET Updated Dec 06, 2017

Climate Change Is a Cause That Should Unite Us All

If ever there were a cause which should unite us all, old or young, rich or poor, climate change must be it.

On Sunday September 21, the world witnessed possibly the largest ever demonstration on climate change in history. Several members of the Elders stood in solidarity with demonstrators at a major march in New York City. Wherever you are, I hope you are making your voice heard.

The science is clear and tells us that human actions are the dominant cause of climate change in the modern era. However, human action can also reverse this trend. This is within our reach, but only if political and businesses leaders set aside their own narrow interests and show leadership that extends beyond the next electoral cycle or the next shareholder meeting.

Today, on September 23, UN Secretary-General Ban Ki-Moon hosts 120 world leaders in New York to prepare a global response to the worsening climate crisis. This summit is yet another milestone of a process that will last months, culminating in the landmark 2015 Climate Change Conference in Paris.

We have a duty to be exceptionally ambitious. As Elders, we have been in politics for some time. We know the importance of bold and visionary words from world leaders. The higher they set their sights, the better the agreement in 2015. We need leadership now, not tomorrow.

new york climate march

From Manhattan to the Maldives, no one escapes the impacts of climate change. After all, its consequences are felt across all societies as the European flood victims, the Philippine typhoon victims or those who bore the brunt of wildfires from California to Australia can attest to. Climate change, as I write this, is causing displacement, fuelling conflict and jeopardizes development across the world.

You could say that either these delegates in New York succeed, or we all fail. But that would be absolving the rest of us from our responsibilities. Let us send a clear and unequivocal signal that failure to act will have consequences at the ballot box for politicians and for the bottom line of businesses. If leaders are unwilling to lead when leadership is required, people must.

Kofi A. Annan is the founding chair of the Kofi Annan Foundationand also chairs The Elders and the Africa Progress Panel. Kofi Annan was the 7th Secretary-General of the United Nations. In 2001, he and the United Nations were jointly awarded the Nobel Prize for Peace.

This post is part of a month-long series produced by The Huffington Post in conjunction with a variety of events being held in September recognizing the threats posed by climate change. Those events include the UN's Climate Summit 2014 (that was held Sept. 23, 2014, at UN headquarters in New York) and Climate Week NYC (Sept. 22-28, 2014, throughout New York City). To see all the posts in the series, read here.