اثر ساختار و عملکرد فضاهای شهری در زون‌بندی نوین اقلیمی مطالعه موردی: منطقه شهری اردبیل

ABSTRACT
Cities are spaces dominated by built environments characterized by specific geometric, surface, and aerodynamic features, creating diverse climatic conditions. The high variability of surface covers presents a mosaic of climates at local and micro scales. Modern tools and methods are required to identify and classify these climates. The Local Climate Zone (LCZ) map is an innovative method for classifying urban climate areas, with a particular focus on identifying urban heat islands. In this study, Landsat 8 satellite images from 2023, covering the months of May, June, August, and November, were used to classify the local climate zones of Ardabil city. A variety of programs and tools were employed during the processing stages for image pre-processing, sampling of climate zones, classification, and numerical analysis. After completing the necessary processes, the local climate map of Ardabil was generated, identifying 14 climate classes. The results revealed that the most common local climate zones in Ardabil were LCZ2 and LCZ3, which include neighborhoods with dense building structures of medium and low heights. Lake Shorabil and the surrounding green spaces within a 7-kilometer radius, in addition to their recreational value, have a significant cooling effect on Ardabil's urban environment. The density of buildings and impervious surfaces like concrete and asphalt have reduced vegetation cover and the potential for natural air circulation and ventilation. This, combined with the increased heat emissions from human activities, has intensified the capacity for urban heat island formation in the city's central areas
Extended Abstract
Introduction
Cities are defined by their unique architectural landscapes, which showcase distinct geometric forms, coverings, and aerodynamic patterns contributing to a diverse climate. The physical characteristics, geometric configurations, and land use/cover of urban spaces fundamentally alter drainage patterns, surface hydrological networks, and groundwater aquifers. These changes also disrupt the balance of energy exchange between the surface and the atmosphere, resulting in a mosaic of climates and temperatures within urban environments. Additionally, cities significantly influence airflow patterns and natural ventilation in neighborhoods, thanks to their three-dimensional layouts. The variety of land cover processes creates a mosaic of climates on local and micro scales, necessitating modern tools and methodologies for classification. One such tool is the local climate zone map, which effectively categorizes urban climate zones and focuses on identifying urban heat islands. A study of numerous articles shows that the preparation of maps of local climate zones is superior to other methods of classification and preparation of urban climate maps due to the attention paid to the human and natural structure of the city about climatic factors and its separation into 17 classes. Ardabil has a dense and compact urban texture consisting of medium-rise and low-rise buildings and narrow alleys that play a minor role in air conditioning.
 
Methodology
This research is applied in nature and employs spatial statistics for analysis. A quantitative approach was utilized, incorporating numerical and documentary data through two primary methods as a literature review and acquiring satellite images and official records for meteorological data and urban information layers pertaining to Ardabil. Landsat 8 satellite images captured in May, June, August, and November of 2023 were utilized to classify local climate zones in Ardabil. Nestled in the northern part of the Ardabil Plain and along the Baliglu Chay River, Ardabil lies in northwestern Iran, close to the border with Azerbaijan, and is separated from the Caspian Sea and Gilan Province by the Tarom Mountains and Heyran Strait. The city features a dense and compact urban fabric composed of medium- to low-rise buildings interspersed with narrow alleys that limit airflow. For the processing and analysis of results, SAGA-GIS software was used for image preprocessing, Google Earth assisted in climatic zone sampling, and ArcGIS was employed for numerical classification and analysis.
 
Results and discussion
After processing the data, we created a local map for Ardabil City, identifying 14 distinct climate classes. Most areas of Ardabil are characterized by dense buildings, particularly in the central and northern halves, which correspond to local climate classes LCZ 2 and LCZ 3. In contrast, the southern half of the city features dense buildings with more open layouts and medium heights. The climate classes characterized by dense, open textures and low to medium heights cover approximately 2,309.79 square kilometers, making up about 18.86% of the study area. Natural covers, including scattered trees, parks, green spaces, and shrubs, classified under local climate classes LCZ A and LCZ B, encompass roughly 139 square kilometers, or 0.7% of the study area. This greenery is distributed throughout the city but is particularly concentrated along the Baliglu River, Tulip Park, Giral Garden, and inner-city pear orchards. These local climate zones play a significant role in moderating the urban climate. In Ardabil, the sky visibility index is relatively low due to the medium and low building density (primarily low-rise structures). However, the sky visibility index is higher in the peripheral areas of the city, thanks to the presence of open spaces, grassy lands, and agricultural zones on the outskirts. Overall, Ardabil enjoys good sky visibility. The local climate map reveals that the aspect ratios in the city's central areas are higher, while peripheral regions and areas outside the city show lower aspect ratios. The percentage of permeable surfaces is notably high in urban areas with tree cover and short grass, whereas impermeable surfaces characterize areas with dense urban development and rocky outcrops.
 
 
Conclusion,
Ardabil is a largely homogeneous city in terms of its texture and function, with most areas classified as LCZ 2, 3, and 8. These classes consist of dense, low-rise buildings as well as large, low-rise structures. The prevalence of buildings and hard surfaces made of concrete and asphalt has significantly reduced vegetation, diminishing natural air movement and ventilation. This, combined with increased heat emissions from human activities, has intensified the urban heat island effect, particularly in the city's central areas. As Ardabil expands southward and construction activity in these regions increases, the need for more green spaces, reduced building density, and improved ventilation through open areas becomes increasingly apparent. Addressing these issues is crucial for alleviating pressure on groundwater resources and enhancing the urban environment.
 
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.