November 23, 2011. Global pledges to cut greenhouse gases need to double by 2020 to contain global warming to 2 degrees Celsius (3.6 degrees Fahrenheit), the United Nations Environment Program said in a report. Current targets at most would slash 6 gigatons (6 billion tons) of carbon dioxide from the predicted 56 gigatons of emissions in 2020 under a “business as usual” scenario. A drop to 44 gigatons, or 6 more, is needed to meet the 2-degree goal, the UN said. The “emissions gap” emphasizes the shortcomings of current action to rein in global warming before envoys from more than 190 countries meet in Durban, South Africa, for two weeks of climate negotiations. The UN also outlined measures in construction, agriculture, power and transportation that could help close the deficit.