Mr Ryan is one of a small number of senior ministers selected to steer talks on the main issues under discussion at the fortnight-long gathering in Baku, Azerbaijan.
He will co-facilitate talks on ‘climate adaptation’ – how countries can prepare for the climate change impacts already evident and those no longer preventable.
The most contentious part of those negotiations will be how to fund adaptation projects, particularly in poorer countries that are the worst affected by climate change but least economically capable of coping with them.
In 2009, the annual Cop summit agreed to gather $100 billion (€89bn) a year from wealthier countries to help poor nations but it took until 2022 to reach that target.
By then, it was already clear that the impacts of climate change were far worse than anticipated and the level of funding would need to dramatically increase.
Mr Ryan will be tasked with getting agreement from richer nations on increasing contributions and on how they should be distributed.
“There’s a real challenge here. Getting agreement is going to be very difficult,” he said.
Mr Ryan will also have to broach the diplomatically sensitive issue of which countries should be donors to adaptation funding and which should be recipients.
Since the first global climate talks in1992, counties have been put into two categories – developed and developing – but the economies of many of those categorised as developing have improved vastly.
For example, China is still officially a developing country.
“A lot of focus will be on what the figure [for adaptation funding] will go to but also on whether there will be a broadening of the contributor base,” Mr Ryan said.
He said the contributor base should be widened beyond simply adding more countries by squeezing industry to play its part.
“There needs to be a mosaic of funding – public, private, philanthropic. If you just focus on that core public funding, that’s not going to deliver the scale of finance we need.”
Mr Ryan, who is not standing in the general election and so will not be affected if it falls during the summit, will co-facilitate with a counterpart from Costa Rica.
Other pairings are Norway and South Africa, Australia and Egypt, Kazakhstan and Singapore and New Zealand.
Asked if he had any difficulty working with a Cop presidency headed by a long-time state oil company executive in a country economically dependent on fossil fuel production, Mr Ryan said he did not.
“If you start differentiating in that way then I couldn’t talk to the Americans because they’re the biggest fossil fuel producer, producing 13 million barrels of oil a day and the largest gas producer by far.
“I also couldn’t talk to the Brazilians because if you look at new fossil fuel production, Brazil’s right up there.
“They all have to agree and understand that we are transitioning away from fossil fuels but how we do that presents very difficult decisions for those countries.”
