"Now, Sandy is an example of what we call a hybrid storm. It works on some of the same principles as the way hurricanes work but it also works on the same principles as winter storms work. Hurricanes and winter storms are powered by completely different energy sources. The hurricane is powered by the evaporation of sea water. Winter storms are powered by horizontal temperature contrasts in the atmosphere. So hybrid storms are able to tap into both energy sources. That’s why they can be so powerful."
要比就苹果和苹果比吧. 美国没有说SANDY是几级的. 你先查查.