By matching maps of snow and ice amounts with maps of net radiation flux for the same time frame, students will use the Live Access Server to explore how the net radiation flux has affected the snow and ice amounts in the Northern Hemisphere, as well as how the presence of snow can affect the net radiation flux due to surface reflection. The lesson includes detailed procedures, related links and sample graphs, follow-up questions, extensions, and teacher notes. This lesson is from the MY NASA DATA project, which has created microsets from large scientific data sets, and wrapped them with tools, lesson plans, and supporting documentation so that a teacher, or anyone in the interested public, can use authentic NASA Earth system science data.