From the tropics to the poles, from small islands to large continents, and from the poorest countries to the richest, climate change impacts are already widespread, costly and consequential, UN Secretary-General Ban Ki-moon said on Sunday, urging stakeholders gathered in Abu Dhabi to consider concrete actions to tackle the phenomenon now — before it is too late.

"Climate change is the defining issue of our time. If we do not take urgent action, all our plans for increased global prosperity and security will be undone," said the UN chief in opening remarks to the "Abu Dhabi Ascent", which he is co-hosting with the UAE to prepare for and build commitment ahead of his Climate Summit, set for Sept. 23 in New York.

More than 1,000 participants, including 100 ministers, have gathered in Abu Dhabi for the two-day event to chart new routes for reducing greenhouse gas emissions and strengthening climate resilience.

The "Ascent" is the first international meeting to draw on the conclusions of the recently issued reports from the UN Intergovernmental Panel on Climate Change, which found the consequences of climate change are already being felt, and that while present action is insufficient, there are still pathways toward a low carbon future that could minimize the phenomenon's impacts. Action now, said the report, is necessary in order to avoid much higher costs in the future.

Thanking the UAE for being pioneers on the journey to a low-carbon future, Ban said: "It is the future we need and we have to lay the foundations today. We have little time to lose. That is why it is important that governments complete a meaningful new climate agreement by 2015 that will rapidly reduce emissions and support resilience."