Climate change will affect some areas of the U.S. far more severely than others, according to a new study by Princeton University researchers published in the journal Climatic Change. Regions that already suffer from heat and humidity in the summer, such as the Southeast and a portion of the mid-Atlantic, will be particularly vulnerable to increased humidity caused by climate change. Within 50 years, the heat index, which measures the stress placed on humans by elevated temperatures and humidity, for New Jersey and areas with similar climates should be about 10 degrees higher in July than it is now. A separate report on climate change by the World Wildlife Fund predicted that the U.S. will become warmer and wetter more rapidly than the world average. It also presented scenarios under which half of Japan’s sandy beaches would be destroyed, large areas of the Amazon would become prone to forest fires, and pest attacks would threaten Russian cities.