And a second fund, meant to jump start the promise, will run dry by Dec. 31.
Canada has given $400 million a year for the last three years to the latter climate fund to provide a down payment for poor countries to begin the work of cutting emissions and adapting to the inevitable effects of global warming.
But that fund drew only three years' worth of financial commitments from donor countries, for a total of $30 billion that will be drained by year's end.
Much of this money was recycled from other aid programs, says the study by Oxfam, an international non-governmental organization.
The larger promise made by rich countries in Copenhagen in 2009 to raise $100 billion a year by 2020 remains in the wind.
"After a year of extreme weather, developing countries face a climate 'fiscal cliff' at the end of 2012, as fast-start finance expires and the Green Climate Fund remains empty," Oxfam said.
When environment ministers, including Canada's Peter Kent, meet in Doha for United Nations climate negotiations next week, they will need to figure out how to come up with the rest of the money, said Christiana Figueres, the top UN climate change official.
"Governments have agreed it is imperative to stay at least below a two degree average global temperature rise to avoid the worst impacts of climate change," she said in a statement to set up the talks. "But they know this cannot be achieved without further dramatic transformation in energy production and use and without effective support to developing nations so they can build their own sustainable futures."
At the widely watched climate talks in Copenhagen in 2009, rich countries agreed to a 10-year financing plan to integrate developing countries into the global effort to reduce emissions and handle climate change.
Donors came forward to provide $30 billion for the first three years of the plan. But Oxfam's analysis shows they did not live up to their commitment to provide new funding that would be balanced between efforts to mitigate climate change on the one hand and adapt to climate change on the other.
Instead, only 33 per cent of the financing was new money, raising concerns that donors siphoned off money from other needy causes.
Only 21 per cent of the funding went to support adaptation to global warming.
That's troubling, because the poorest of poor countries have very low emissions but bear the brunt of extreme weather events increasingly caused by global warming, said Mark Fried of Oxfam Canada.
He said only 10 per cent of Canada's money went towards adaptation.
Canada has yet to earmark $183 million of its $1.2-billion pledge for the fast-start program, and Fried wants Kent to put it towards adaptation efforts.
But the larger problem is the lack of funding starting in 2013.
As ministers hash out ways to sign a meaningful climate agreement by 2015 that would go into force in 2020, they also have to deal with raising $100 billion a year, Figueres said.
Oxfam says it will be a tough discussion since so many rich countries are dealing with fiscal problems. In Canada, the federal government has shown no indication it will find more money for the climate financing fund after the end of this year.
That's why countries should be looking at a tax on international shipping or on financial transactions, said Tim Gore, Oxfam International's climate change policy adviser.
"If leaders come to Doha with no new money, the Green Climate Fund risks being left as an empty shell for the third year in a row," he said.