With every degree Fahrenheit rise in temperature, the atmosphere can hold 4 percent more moisture. As a result, Sandy was able to pull in more moisture, fueling a stronger storm and magnifying the amount of rainfall by as much as 5 to 10 percent compared with conditions more than 40 years ago, said Kevin Trenberth, a senior scientist at the National Center for Atmospheric Research, a federally funded research and development center. Coupled with higher sea levels -- since 1992, satellites have observed a 2.25-inch rise -- that means more water to surge onshore and penetrate farther. "That may not sound like a lot," he said. But "a small increase in sea level can actually make a big difference."
MCCLATCHY NEWS SERVICE