WARSAW, Poland – After another U.N. climate conference gave only modest results, European Union Climate Commissioner Connie Hedegaard says the process needs to provide a “substantial answer” to global warming in two years to remain relevant.

Even if it succeeds, it’s worth reconsidering whether the international conferences need to be held every year, and whether the scope of each session should be narrower, Hedegaard told the Associated Press on Sunday. “Maybe it would be time now to think if there should be themes for the conferences so that not each conference is about everything,” the commissioner from Denmark said in a telephone interview.

In two decades, the U.N. talks have failed to provide a cure to the world’s fever. Heat-trapping carbon emissions that scientists say are warming the planet are growing each year as most countries still depend on coal and oil to fuel their economies.

Besides those emissions, the U.N. talks deal with a range of complex issues, including monitoring and verification of climate actions, accounting rules, and helping developing countries cope with the rise in sea level, desertification and other climate effects as they make a transition to clean energy.

The two-week session that ended here Saturday nearly collapsed in overtime before agreements were watered down to a point where no country was promising anything concrete.

On the final day, sleep-deprived delegates spent hours wrangling over the wording of paragraphs and bickering over procedure, such as when Venezuela questioned why the United States got to speak before Fiji in the plenary.

As the gavel dropped, negotiators emerged with a vague road map on how to prepare for a global climate pact they’re supposed to adopt in two years – work that Hedegaard said will be crucial in answering whether the world still needs the U.N. process. “I think that it has to deliver a substantial answer to climate change in 2015,” Hedegaard said. “If it fails to do so, then I think this critical question will be asked by many more.”

Many climate initiatives are happening far from the U.N. negotiations, as local and national governments pursue low-carbon energy sources and energy efficiency. Even international efforts are increasingly taking place outside the U.N. climate framework. Governments are working together to slash funding for coal projects, reduce soot and other short-lived climate pollutants and to phase out subsidies for fossil fuels.

China and the United States – the world’s two biggest carbon polluters – this year agreed to work jointly on energy efficiency, carbon capture technology and other mitigation projects.

“This was a missed opportunity to set the world on a path to a global climate deal in 2015, with progress painfully slow,” said Mohamed Adow, a climate change adviser at Christian Aid. “We need a clear plan to fairly divide the global effort of responding to climate change and a timeline of when that will happen,” he said.

U.N. studies show that global emissions need to peak in 2020 and then start falling to stabilize warming at 3.6 degrees Fahrenheit, or 2 degrees Celsius, a level that countries hope will avoid the worst consequences of climate change.