Devastating extreme weather including recent flooding in England, Australia's hottest year on record and the U.S. being hit by a polar vortex have a "silver lining" of boosting climate change to the highest level of politics and reminding politicians that climate change is not a partisan issue, according to the U.N.'s climate chief.

Christiana Figueres said that it was amoral for people to look at climate change from a politically partisan perspective, because of its impact on future generations.

The "very strange" weather experienced across the world over the last two years was a sign "we are already experiencing climate change," the executive secretary of the U.N. climate secretariat told the Guardian.

The flooding of thousands of homes in England because of the wettest winter on record has brought climate change to the forefront of political debate in the UK. The prime minister, David Cameron, when challenged by Labor leader, Ed Miliband, on his views on man-made climate change and having climate change skeptics in his cabinet, said last week: "I believe man-made climate change is one of the most serious threats that this country and this world faces."

Climate change was barely mentioned at all in the 2012 U.S. election battle until to endorse Barack Obama's candidacy because he would "lead on climate change."

Figueres said: "There's no doubt that these events, that I call experiential evidence of climate change, does raise the issue to the highest political levels. It's unfortunate that we have to have these weather events, but there is a silver lining if you wish, that they remind us is solving climate change, addressing climate change in a timely way, is not a partisan issue."

She added: "We are reminded that climate change events are for everyone, they're affecting everyone, they have much, much longer effects than a political cycle. Frankly, they're intergenerational, so morally we cannot afford to look at climate change from a partisan perspective."

Figueres said that examples of recent extreme weather around the world were a sign climate change was here now. "If you take them individually you can say maybe it's a fluke. The problem is it's not a fluke and you can't take them individually. What it's doing is giving us a pattern of abnormality that's becoming the norm. These very strange extreme weather events are going to continue in their frequency and their severity. It's not that climate change is going to be here in the future, we are experiencing climate change."

Figueres was speaking in London before meeting businesses including Unilever, Lafarge and Royal Dutch Shell to urge them to put pressure on governments to take action on climate change, ahead of renewed international negotiations in Bonn next week to flesh out details of a draft climate treaty to be laid out in Lima this year and agreed in Paris at the end of 2015.

"2014 is a crucial year because of the timing of next year, in 2015 there will be very little time work on the actual agreement. We have to frontload the work," she said.

Peru's foreign minister said in January that the Lima meeting in December must produce a first draft of a deal to cut carbon emissions, which will be the first of its kind after efforts to get legally binding agreement for cuts from most of the world's countries failed at a blockbuster meeting in Copenhagen in 2009.

Asked if a bad deal was better than no deal next year, she said: "Paris has to reach a meaningful agreement because, frankly, we are running out of time." But she dismissed parallels with the run-up to the Copenhagen summit, saying the frequency of extreme weather events, lower renewable energy costs and progress on climate legislation at a national level meant it was different this time round.

"I hope that we don't need too many more Sandys or Haiyans or fires in Australia or floods in the UK to wake us up. My sense is there is already much momentum. We have 66 governments that have climate legislation, we have a total of 500 laws around the world on climate, whereas before Copenhagen we only had 47."

But the grouping of the world's 47 "least developed" countries said this week that they would want far more money to adapt their economies to climate change than the $100 billion a year that been so far proposed by rich countries.

"We will want more than the $100 billion to agree to a new Paris protocol," said Quamrul Choudhury, a lead negotiator for the group which includes many African and Asian countries. "On top of that we will want a legal mechanism to compensate for ‘loss and damage' compensation for extreme climate change events. There should definitely be some space in the final treaty for that," he said in London.

He called on rich countries to compromise. "The battle lines are drawn. Everyone wants to defend their country and nobody will give an inch, but everyone has to make some sacrifice or we won't have a deal. We need high-level political commitment to raise ambition."

Choudhury, who is also Bangladesh's climate envoy to the United Nations, met British climate negotiators ahead of the Bonn talks. "I am optimistic that the world can avoid another diplomatic disaster like Copenhagen in 2009. There have been major changes since then. In 2008-09 we knew it would be very expensive to reduce emissions. Now we know it does not cost very much. It's not expensive, not a Herculean task. Countries like the UK know they can reduce emissions by 65 percent without it costing very much at all. "

But even if we have an ambitious mitigation target to cut emissions adaptation must be the cornerstone of a new treaty. This is not a zero-sum game. If we treat it like that there will be no Paris protocol," he said.

Figueres later agreed that the $100 million proposed in 2009 as compensation for poor countries would not be enough for them to build defenses and adapt their economies. "The International Energy Agency has suggested it may cost $1 trillion over 25 years just for adaptation. $100 billion is a freckle on the map of what needs to be invested."

A major U.N. climate science panel report to be published at the end of this month will spell out the impacts of climate change on humanity and the natural world. Leaked versions of the report say agricultural production will decline by up to 2 percent every decade for the rest of the 21st century.