Tehran’s Ecosystem Resilience Against Air Pollution

In this research, we develop a method for measuring resilience for Tehran’s ecosystem against air pollution. Resilience has been proxied by the largest Lyapunov exponent (LLE), so that the positive LLE, which indicates a chaotic system, implies a weak resilience. The data used in this study is the daily average of the Air Quality Index (AQI) in 1826 day for the period 1390-1394 (2000-2014). The results show a positive LLE in the AQI, implying a chaotic system. Therefore, resilience of Tehran’s ecosystem against air pollution can be considered weak, making it vulnerable in confronting with shocks. Hence, attention to resilience in economic decision-making and urban management is very important.