Scientists: Global Warming Could Wipe Out ¼ Of All Species Local Group: Swift Action by Congress, Pennsylvania Could Help Avert Worst Predicted Impacts POSTED: 12:52 pm EDT April 6, 2007 UPDATED: 1:26 pm EDT April 6, 2007 Approximately 20 to 30 percent of plant and animal species are at risk of extinction if the global average temperature increases by another 2.2 to 4 degrees Fahrenheit, according to a major consensus report released Friday by the Intergovernmental Panel on Climate Change. The IPCC is a United Nations body charged with assessing the scientific record on global warming. "More droughts, floods, forest...