Climate change to disrupt food supplies, brake growth-UN draft
* Climate may already be having irreversible impact-draft
* New U.N. report to raise pressure on governments to act
By Alister Doyle, Environment Correspondent
OSLO, March 23 (Reuters) - Global warming will disrupt food supplies, slow world economic growth and may already be causing irreversible damage to nature, according to a U.N. report due this week that will put pressure on governments to act.
A 29-page draft by the Intergovernmental Panel on Climate Change (IPCC) will also outline many ways to adapt to rising temperatures, more heatwaves, floods and rising seas.
"The scientific reasoning for reducing emissions and adapting to climate change is becoming far more compelling," Rajendra Pachauri, chair of the IPCC, told Reuters in Beijing.
Scientists and more than 100 governments will meet in Japan from March 25-29 to edit and approve the report. It will guide policies in the run-up to a U.N. summit in Paris in 2015 meant to decide a deal to curb rising greenhouse gas emissions.
The 29-page draft projects risks such as food and water shortages and extinctions of animals and plants. Crop yields would range from unchanged to a fall of up to 2 percent a decade, compared to a world without warming, it says.
And some natural systems may face risks of "abrupt or drastic changes" that could mean irreversible shifts, such as a runaway melt of Greenland or a drying of the Amazon rainforest. Continuación...