If humans don't curb use of fossil fuels, the planet will warm 14.5 degrees Fahrenheit by the year 2300. The polar ice caps will disappear and oceans will rise 23 feet (7 meters). That's the conclusion of climate simulations released today by scientists at the Lawrence Livermore National Laboratory. At the poles, the average temperature would rise more than 36 degrees Fahrenheit (20 degrees Celsius), the model predicts. "The temperature estimate is actually conservative because the model didn't take into consideration changing land use such as deforestation and build out of cities into outlying wilderness areas," said Govindasamy Bala of...