LiveScience: A 50 percent increase in the number of lightning strikes within the United States can be expected by 2100 if temperatures continue to rise due to greenhouse gas emissions, a new study claims. Researchers found a 12 percent increase in lightning activity for every 1.8 degrees Fahrenheit (1 degree Celsius) of warming in the atmosphere, according to the study, published on Nov. 13 in the journal Science. Without emissions cuts, scientists expect this century to end with global temperatures that are...