A new study shows that traffic-related pollution in a major urban area in central Israel produces immediate, measurable changes in the atmospheric electric field, while particulate matter creates slower, delayed effects. The research also identifies a strong weekend signal, with reduced emissions leading to a marked weakening of the electric field. These findings are important because they point to atmospheric electricity as a highly sensitive, real-time indicator of urban air quality, capable of detecting rapid changes in emissions that conventional monitoring may miss. The results suggest a new way to track the immediate impact of traffic patterns and emission-reduction policies on city air, with potential implications for urban planning, environmental monitoring, and public health.