Environmental activists protest during the 19th conference of the United Nations Framework Convention on Climate Change (COP19) in Warsaw November 21, 2013 Kacper Pempel/Reuters

Some scientists have concluded that climate change has played a role in the increase in the frequency and ferocity of weather events around the world. And research has shown that humans are the primary cause of changes to the climate , such as global warming.

"We can fix this. We can stop this madness. Right now, right here," he told the delegates.

Philippine envoy Naderev "Yeb" Sano broke down in tears speaking at the conference about the death and destruction caused by the storm, and announced he would fast until a "meaningful outcome is in sight."

The conference began Nov. 11 on an emotional note as Typhoon Haiyan's winds made a "devastating impact" on the Philippines, U.N. climate chief Christiana Figueres said during her opening speech while urging delegates to "go that extra mile" in their negotiations.

A draft text presented Friday at the two-week conference gave only vague direction on when countries should present their targets for restricting carbon emissions. That's a key element of the deal that's supposed to be adopted in Paris in 2015.

With the United Nations climate talks in Warsaw , Poland, drawing to a close, environmental groups and country representatives say little has been achieved, with a strong divide between developed and developing nations preventing any meaningful agreement.

The US does not accept enough responsibility for its part in creating the catastrophe in the Philippines

The U.N. climate talks were launched in 1992 after scientists warned that humans were warming the planet by pumping carbon dioxide and other heat-trapping gases into the atmosphere, primarily through the burning of fossil fuels.

This year's global conference was bogged down by recurring disputes over who needs to do what, when and how, in order to slow the effects of climate change.

On Nov. 20, with two days left in talks, negotiators for developing nations, including China, walked out of a meeting about compensation for countries most severely affected by global warming.

Bolivia and other developing countries have accused wealthier nations of failing to show willingness to discuss aid or compensation for losses and damage, such as rising sea levels and creeping desertification, widely blamed on global warming.

"We do not see a clear commitment of developed parties to reach an agreement," said Rene Orellana, head of Bolivia's delegation.

One day after that walkout, six environmental groups followed suit, declaring that the ailing talks were "on track to deliver virtually nothing."

Greenpeace spokesman Gregor Kessler said the groups were "leaving this year's conference for good today."

He said the delegations, or at least that of Greenpeace, would not leave Warsaw altogether but would "follow the discussions from the outside."

"We will not be part of the internal discussions," Kessler said.

The other groups were the World Wildlife Fund, Oxfam, ActionAid, the International Trade Union Confederation and Friends of the Earth.

On the last day of the conference, delegates are expected to put in overtime in order to hash out some kind of deal.

Deputy Environment Minister Beata Jaczewska of host nation Poland predicted a "sleepless night" ahead. "But we are still hoping to close the meeting as soon as possible," she said.

Delegates made progress on advancing a program to reduce deforestation in developing countries, an important source of emissions because trees absorb carbon dioxide.

Disputes persisted on climate financing. Rich countries have promised to help developing nations make their economies greener and adapt to rising sea levels, desertification and other climate impacts.

Island nations that fear being submerged as the seas rise also demanded a new "loss and damage mechanism" to deal with weather disasters made worse by climate change.

Tony DeBrum, minister-in-assistance to the president (equivalent to vice president) of the Marshall Islands, told Al Jazeera he has no choice but to be optimistic.

"I come from the Marshall Islands, one of the most vulnerable areas in the world for climate change. It's not just about a meeting, it's a matter of survival," DeBrum said.

"Some countries are giving up and saying, 'There's nothing we can do.' Some walked out, but we cannot afford to walk out. Where are we going to go?"

Al Jazeera and wire services