What is the difference between Meteorology and Atmospheric Sciences?

Honestly, you won't find much difference between curriculums in a meteorology program versus an atmospheric science program. Technically, Oscar is right. Atmospheric science refers to much more broad subject matter, which could include air quality and interactions between land and atmosphere. Meteorology would be more restricted to weather forecasting and weather patterns. But programs like Penn State, which offer a degree in meteorology, have evolved to the point where the curriculum offers the same type of courses you would expect in an atmospheric science program...they just haven't bothered to change the name of the major. So in summary, technically there is a difference, but if you're dealing with universities and coursework, you probably won't see much of a difference.