Weather and crime—seems pretty intuitive to say that crime comes down either when the temperature, or the rain, does, right? Makes sense, right?
But what about seasons, time of day (or night) and weather? In a recent study published in Crime Science, Lisa A. Tompson and Kate J. Bowers at University College London apply recent developments in weather data availability and statistical modeling to test various hypotheses about weather and crime, and what they found depended on the time of day.
About the study
In their article, “Testing time-sensitive influences of weather on street robbery,” Tompson and Bowers correlated street robbery data from the Strathclyde, Scottland police. Strathclyde covers the Inner Hebrides all the way down to Glasgow, and falls in a temperate oceanic climate zone which is warmed somewhat, compared with similar latitudes, by prevailing winds off the Gulf Stream. They correlated the robbery data with weather data provided by Glasgow Airport (weather station EGPF on Wunderground.com). They looked at all weather conditions, not only temperature, but rain and wind, as well. They applied various statistical modeling techniques and regressions to see what correlations might exist between these data sets.
The two hypotheses that Tompson and Bowers set out to test are the adverse-favorable weather hypothesis, which suggests that people venture outside less when the weather is bad (or worse than their seasonal expectations), and the discretionary activities hypothesis, which suggests that people plan and postpone their discretionary activities based on their expectations of weather conditions.
They found that the two hypotheses had different explanatory power depending on which time period they studied—that is, the various seasons or the day shift versus the night shift. They found that the adverse-favorable hypothesis could explain the statistical correlations during the winter months, yet the discretionary activities hypothesis fit better with robbery/weather patterns at night and weekends. They write,
Collectively these results produced greater explanatory power for the variation in robbery at the shift level than has been seen in prior research, which we think is related to the important influence of discretionary activity time on a crime type such as robbery, and the fine-grain unit of analysis chosen to study weather and robbery (the 6-hour shift). Such a micro-temporal level approach is critical to observing the variation of weather over the course of the day, and over other temporal scales…
In turn this wisdom can help crime reduction agencies to advantageously position their resources to inhibit crime from occurring. We assert that weather should be considered alongside other situational variables, particularly during times of discretionary activity or noticeably favourable weather conditions in planning resource allocation.
You can find the entire study here.