It is unknown if cloud cover increases in response to carbon dioxide levels changing, helping climate change slow down, or if cloud cover decreases, allowing Earth to warm faster. Part four in the series of five lessons has classes explore other factors that are impacted by an increase in carbon dioxide. Participants analyze and discuss temperature, precipitation, and cloud cover data. Following those activities, individuals then use the MY NASA DATA website to determine if global patterns of climate change are happening in their areas and specific cities around the world.