Worldwide investments in limiting climate change are far too low and as flimsy as using an umbrella in a hurricane, the United Nations climate chief Patricia Espinosa said on Wednesday.
Espinosa, a former Mexican foreign minister, also told delegates from almost 200 nations meeting in Germany that more storms, droughts and floods linked to man-made greenhouse gas emissions threatened "global destabilisation".
She urged far more investments to limit global warming, by shifting from fossil fuels towards cleaner energy, and to protect people from the worsening effects of extreme weather.
"Trying to address climate change at current financing levels is like walking into a Category 5 hurricane protected by only an umbrella," she said in a speech.
"Right now we are talking in millions and billions of dollars when we should be speaking in trillions," said Espinosa, who is head of the U.N. Climate Change Secretariat. "The impacts of extreme weather are already creating chaos."
Nations at the April 30-May 10 meeting in Bonn are working on a detailed rule book for the 2015 Paris Agreement, aiming to have it in place by the end of 2018, and are reviewing actions so far to limit global warming.
Developing nations at the talks want firmer guarantees of funds - rich nations have promised to mobilise $100 billion a year in climate finance, from both public and private sources, by 2020 to help them tackle warming.
The Organisation for Economic Cooperation and Development has estimated that climate finance for the poor totalled $62 billion in 2014. Developing nations say the accounts are exaggerated.
"There remains a vast gap between the support needed and support received," Gebru Jember Endalew, who chairs the least developed nations group, said in a statement.
Espinosa said average world surface temperatures were set to rise by 3.0 degrees Celsius (5.7 Fahrenheit) above pre-industrial times, based on current commitments to curb greenhouse gas emissions.
The Paris Agreement seeks to limit warming to "well below" a 2C rise. U.S. President Donald Trump, who doubts climate change is primarily man-made, plans to quit the Paris pact and instead promote domestic fossil fuels.
Espinosa said a three degree rise "will lead to nothing less than global destabilisation. It will cost lives. It will raise competition over resources, it will increase instability and conflict."
Inia Seruiratu, Fiji's agriculture minister who is tasked with driving more ambitious action to meet Paris Agreement targets, said countries face limits on how much they can adapt to coming changes - such as worsening cyclones.
"We live in constant fear that a direct hit from intensifying cyclones could wipe out our economy altogether and set back our development by decades," he said in Bonn.
(Reporting By Alister Doyle; editing by David Stamp)