Wall Street Journal: A key United Nations report is expected to suggest that governments will have to drastically reduce greenhouse-gas emissions to meet international goals to reduce the impact of global warming. Based on the current trend of emissions, the global temperature is projected to increase by 2 degrees Celsius (3.6 degrees Fahrenheit) above preindustrial levels in less than three decades, according to a draft summary reviewed by The Wall Street Journal. Projections suggest that beyond the two-degree point...