The cost to poor countries of adjusting to ever-hotter temperatures will be twice or even three times higher than previously thought, the U.N.'s environment agency said Friday — and that assumes a best-case scenario in which greenhouse gas emissions are dramatically reduced. "If you don't cut emissions, we're just going to have to ask for more money because the damage is going to be worse," Ronald Jumeau of the Seychelles said at U.N. climate talks in Lima, Peru.

The report was bound to sharpen disputes in Lima over who pays the bills for the impacts of global warming, whose primary cause is the burning of coal, oil and gas but which also includes deforestation. Rich countries have pledged to help the developing world convert to clean energy and adapt to shifts in global weather that are already adversely affecting crops, human health and economies. But poor countries say they're not seeing enough cash. Projecting the annual costs that poor countries will face by 2050 just to adapt, the United Nations Environment Program report deemed the previous estimate of $70 billion to $100 billion "a significant underestimate." The report says new studies indicate the costs will likely be "two to three times higher," possibly even as high as $500 billion.

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1 man turned degraded land into a forest – work is underway to green landscapes for millions more in #Africa: http://t.co/7pdDxJS9fF #COP20 — World Bank (@WorldBank) December 5, 2014

Northern extension of Fiddler Crabs’ range may be sign of #climatechange http://t.co/VAN5bM0Lzv Pic by D.Johnson pic.twitter.com/nznk3Uw23n — USGS (@USGS) December 5, 2014

— The Associated Press