There is a misconception among undergraduate students that global warming is caused by holes in the ozone layer. In this study, we evaluated the presence of this and other misconceptions surrounding atmospheric chemistry that are responsible for the entanglement of the greenhouse effect and the ozone hole in students' conceptual frameworks. We then designed a series of computer-based online data-analysis exercises to address this shortcoming and measured the effectiveness of these instructional materials in a first-year general chemistry class. Based on pre- and post-activity assessments, students demonstrated a moderate improvement in their conceptual understanding from the online exercises alone, and student performance was greatly enhanced when the online exercises were supported with both lecture and small-group discussion activities. The integration of individual online learning and data analysis with these more traditional methods of instruction allowed students to address their prior misconceptions and ultimately construct a more scientifically accurate understanding of atmospheric environmental chemistry. (Contains 2 figures.)