Climate-Adaptive Urban Morphology: A Case Study of the Sang-e-Siah Historical Neighborhood in Shiraz City

Document Type : Research article

Authors

Department of Urban Planning and Design, Faculty of Art and Architecture, Shiraz University, Shiraz, Iran

10.22059/jurbangeo.2024.379647.1972

Abstract

ABSTRACT
The expansion of modern cities, the resulting environmental consequences, and the need to ensure human comfort in urban spaces have introduced new challenges for urban development designers. The morphological structure of cities, comprising patterns of streets, blocks, and urban areas, can significantly alter micro-climate conditions compared to macro-climate conditions, thereby influencing the thermal comfort of urban space users. Ancient Iranian architecture, known for its harmony with the macro climate, offers valuable insights through the historical textures of its cities, serving as three-dimensional documents of climate-adaptive design solutions. This research focuses on the Sang-e-Siah historical neighborhood in Shiraz City, utilizing documentary and library studies, field surveys, and GIS software simulations to analyze historical morphological conditions compatible with Shiraz’s climate systematically. The findings reveal that the morphology of the Sang-e-Siah neighborhood, with its winding streets, high height-to-width ratios, limited sky visibility, semi-open spaces, complex block forms, and strategic building orientations, effectively mitigates hot afternoon radiation, blocks hot winds, and enhances shading and ventilation. These features collectively improve the thermal comfort of the area’s users. In conclusion, this study presents a design framework for climate-compatible urban morphology based on the historical context of Shiraz, offering guidelines to enhance thermal comfort in contemporary urban spaces.
Extended Abstract
Introduction
As technology has advanced and cities have grown, people have increasingly shaped their environments to suit their needs, creating unique microclimates in their urban areas. This shift from natural landscapes to urban spaces has brought about significant changes in local climates, mainly influenced by how cities are designed and laid out. The arrangement of streets, blocks, and public spaces can significantly impact local temperature and comfort levels, making the role of urban planners and designers crucial in ensuring outdoor spaces remain comfortable and healthy. In contrast to modern cities, which often follow similar development patterns regardless of their climate, traditional architecture was carefully adapted to its local environment. These historic buildings were designed to take full advantage of their climate, reducing negative environmental impacts while enhancing comfort. This research focuses on understanding how urban design influences microclimatic conditions and thermal comfort in public spaces, with a particular look at the historical city of Shiraz. By examining the Sang-e-Siah neighborhood, the study aims to develop a design approach that aligns with Shiraz’s specific climate. Key questions include:

What urban design features affect microclimate and comfort in public spaces? 2. How has the Sang-e-Siah neighborhood adapted its design to Shiraz’s climate?
What design strategies can ensure future developments are compatible with Shiraz’s climate?

 
Methodology
This research is applied and follows a descriptive-analytical approach, combining documentary and library studies. Here is how the study was conducted:
1-Literature Review: We reviewed existing research to pinpoint the key morphological indicators and criteria influencing thermal conditions in urban open spaces.
2- Historical Analysis: Next, we examined historical documents such as maps and photographs to uncover how the Sang-e-Siah neighborhood’s historical layout adapted to its climate.
3-Simulation and Analysis: Using GIS software, we created a two-dimensional simulation of the historical urban layout. This allowed us to quantitatively analyze various morphological characteristics, including passage widths, block shapes, and overall granularity.
4-Data Calculation and Visualization: Finally, we used Excel to compute additional indicators, such as the percentage of built-up versus unbuilt areas, the building coverage ratio, and more. Excel also helped us create charts to visualize these findings.
Through this process, we gained insights into how the historical design of the Sang-e-Siah neighborhood effectively responds to its climatic conditions.
 
Results and discussion
The research data reveal fascinating patterns in the study area’s layout. The passages are arranged with a unique hierarchy, oriented between 30 to 60 degrees and 120 to 150 degrees relative to the north. These passages have a height-to-width (H/W) ratio exceeding. Their relatively short lengths and semi-open spaces limit sky visibility, creating a distinctive urban environment.
The blocks’ organic shapes show a ground surface index (GSI) of 70 to 80% and a building coverage ratio (BSC) of 100 to 120%. They have a low unbuilt space ratio of 0.17 to 0.29, which helps shield them from direct climatic effects and strong winds.
Typically, the study areas range from 100 to 800 square meters. They stretch from the northwest to the southeast, and each has at least one access point to a main road. Most of these areas are residential, with public occupancy levels between 70% and 90%. The limited open spaces are often organized into smaller areas, following a double--, triple--, or quadruple construction pattern. This setup provides residents with both private and semi-private outdoor spaces.
Overall, the unique arrangement of passages and blocks in the study area not only contributes to its distinctive microclimate but also offers a protective shield from extreme weather conditions, ensuring the safety and comfort of its residents.
 
Conclusion
This research uncovers the unique features of the historical layout of the Sang-e-Siah neighborhood in Shiraz, which has been skillfully adapted to its climate. The design effectively reduces radiation exposure and enhances shaded areas by positioning passages to harness prevailing winds and incorporating semi-open spaces. Using water features and vegetation further increases local humidity, creating a more comfortable environment.
The findings of this research have significant implications for future urban development in Shiraz. It is advisable to incorporate the historical design principles uncovered in this study. This means considering safe increases in wall heights, expanding shaded areas with vegetation, and using semi-open spaces inspired by historical patterns. Urban blocks should feature organic shapes with a thoughtful mix of open, semi-open, and enclosed spaces to serve public and private needs. Additionally, public areas should be designed to maintain a minimum occupancy of 60% and follow traditional Isfahan city orientation. By adopting these approaches, future developments can better align with Shiraz’s climate and minimize any adverse microclimatic effects.
 
Funding
There is no funding support.
 
Authors’ Contribution
Authors contributed equally to the conceptualization and writing of the article. All of the authors approved thecontent of the manuscript and agreed on all aspects of the work declaration of competing interest none.
 
Conflict of Interest
Authors declared no conflict of interest.
 
Acknowledgments
 We are grateful to all the scientific consultants of this paper.

Keywords


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