Pollution, extreme weather, and global warming have become increasingly important in today’s society. This dissertation examines these topics in three chapters, analyzing the effects of pollution and environmental factors on human behavior. The first chapter uses a dataset of unique daily crimes in the U.S. to unveil the relationship between weather/pollution and the crime rate for seven major U.S. cities. The results reveal that temperature significantly affects both violent and property crime rates. The rate of violent crime is lower on extreme and unpleasant weather days (i.e., when the temperature is above 99°F) in comparison to good or unremarkable days. There is little evidence on how air pollution affects the crime rate by using fine...