Climate Change and the Challenges of Quantitative Assessment of Urban Climate Change: A Case Study in Tehran Metropolis

Background and Aim: Climate change on the earth is changing faster than ever before in the history. Cities are highly vulnerable to this climate change. Therefore, the present study aimed to investigate climate change in the metropolis of Tehran during the period 1991-2020 and help understand the limitations that cities may have in confronting climate change. Materials and Methods: This descriptive-analytical study was performed based on the information obtained from the synoptic stations in the Tehran metropolis. First the relevant indicators were determined based on the opinions of experts and the existing literature, followed by analyzing the descriptive and analytical data on climate using the EXCEL-2016 software. Finally, based on reviewing the studies in the literature and analysis of climate data in the metropolis of Tehran, a single protocol was arrived at to study climate change in the city (microclimate) and how to reduce, and adapt with, the impacts of climate change in cities. Results: Analysis of the data showed that the metropolis of Tehran had been facing an increase in temperature and a decrease in humidity over the preceding 30 years. The average monthly temperature increase and humidity decrease had been about 1.5° C and nearly 15%, respectively. Conclusion: Tehran metropolis is faced with an increase in temperature and a decrease in humidity levels, the intensity of both of which will further increase in the future. Dense urban population areas will experience more intense climate change due to the formation of heat islands. To deal with this problem urban planners must consider urban socio-economic development in the context of adapting to climate change and reducing its impacts in various urban areas.