Journal of Climate Research

Journal of Climate Research

Study of the role of vegetation on the formation of heat islands in Tehran City (district 6)

Document Type : Original Article

Authors
Arian Zarfeshani
Mohammad Hossein Jahangir
Faraz Alijani
University of Tehran
10.22034/jcr.2026.269386.1408
Abstract
Extended Abstract:

Introduction

A simple study of the environment reveals that cities have expanded greatly in both the horizontal and vertical directions over the past two or three decades. This problematic phenomenon has caused the areas that in the not so distant past were full of various plants to be replaced with dark concrete and asphalt. This has a tremendous impact on the weather in different parts of the city, from a micro-meteorological point of view (small-scale meteorology). One of the obvious consequences is an increase in temperature in places that have more and more dense buildings in particular, and vegetation has a low density. Urban heat island development occurs when a large portion of the earth's natural vegetation in an area is replaced by man-made surfaces, resulting in low moisture due to lack of vegetation and impermeable surfaces absorbing large amounts of solar radiation during the day and then during the night Is reflected. In one city, the temperature is often 3 to 4 degrees Celsius higher than in other non-urban areas.The difference between the temperature of the heat waves and the environment around the intensity of the heat waves is called so that the higher the temperature of the heat waves than the environment, the higher the intensity of the heat waves, the intensity of urban heat waves can vary between 0 to 7 degrees Celsius depending on the season, sunlight and city characteristics. On a hot summer day, the sun warms homeless, dry surfaces such as rooftops and hard street surfaces, sometimes up to 20 to 50 degrees Celsius, while shady or humid surfaces, often on the outskirts of the city, have temperatures around the temperature. They have air. Urban heat islands exist during the day and night, but are more intense during the day when the sun shines.

Materials and Methods

Tehran province is located in the center of Tehran, with an area of about 12981 square kilometers, between 34 to 36.5 degrees north latitude and 50 to 53 degrees east longitude. This province is limited to Mazandaran province from the north, Qom province from the south, Markazi province from the southwest, Alborz province from the west and Semnan province from the east. The capital of this province is Tehran. Tehran is also the capital of Iran. District 6 of Tehran is one of the relatively old districts of Tehran, which is geographically located in the central part of Tehran. In order to verify the information obtained from this study, the obtained data were compared with the data of the Geophysic Synoptic Station of the University of Tehran. This station is very close to the study area and this is the reason for its selection. Land surface temperature can be described as; the sensation of heat when the ground is touched by hand or skin. The Land surface temperature is finally calculated by the following equation.

T_s=TB/(1+(λ × TB/ρ)Lnε)

The following equation is used to convert surface temperature to air temperature.

Ta=0/14+6/44×LST

Results and discussion

Table 4, Validation of information obtained

seasons Geophysical station air temperature (℃) Calculated air temperature (℃) Temperature difference (℃)

Autumn 8/6 11/2 2/6

Winter 5/2 4/18 1/02

Spring 18/3 17/2 1/1

Summer 30/11 28/74 1/37









In order to validation the results obtained from the study and the data of the Geophysical Station of the University of Tehran were compare and the following table is presented.





















Figure 3 Temperature map of district 6 of Tehran

Figure (3) shows the temperature map in summer, this map is classified into 5 temperature levels and temperatures above 30 ° C have been identified as thermal islands. Green areas indicate temperatures below 27.5 ° C, the average temperature in summer is 28.36 and the average temperature of the heat islands in summer is 30.24 ° C and the average intensity of the heat islands is 1.88 degrees Celsius.

























Figure 4 Map of vegetation and Heat islands of District 6 of Tehran City

In places where there is good and dense vegetation, the temperature is lower and the reason for the low temperatures of the temperature map is the presence of vegetation.

Conclusion

Based on the results of this study, it can be summarized that one of the main reasons for the temperature balance in an environment is the presence of vegetation, and in the absence of it, the ambient temperature increases and using vegetation in areas where the intensity Heat islands are high and rising, can help lower the temperature. The reason for this can be summarized as follows: by changing the materials of urban surfaces and increasing the permeability of water and moisture, which is all achieved by replacing these surfaces with plants, and as a result, plants heat later than impermeable surfaces such as asphalt and concrete.
Keywords
Thermal energy
heat islands
satellite images
climate change
temperature estimation
1.        Aghili Nasab, Z., Mohammadzad, M., Salman Mahini, A., Zarei, Hossein., (2014), Analysis of urban heat islands using remote sensing and its relationship with environmentally friendly development, environment And Development, 4 (8), 79-88.
2.        Akbari, H., Pomerantz, M., & Taha, H. (2001). Cool surfaces and shade trees to reduce energy use and improve air quality in urban areas. Solar energy, 70(3), 295-310.
3.        Alavipanah, S. K., Darrehbadami, S. H., & Kazemzadeh, A. (2015). Spatial-Temporal Analysis of Urban Heat-Island of Mashhad City due to Land Use/Cover Change and Expansion. Geogr Urban Plan Res, 3(1), 1-27.
4.        Alijani, B., Safavid, Y. (2006), A Study of Geographical Factors of Air Pollution in Tehran, Journal of Geographical Research, No. 38 (58), 112-99.
5.        Alijani, B., Tulaeinejad, M., Sayadi, F. 1396, Calculation of thermal island intensity based on the studied urban geometry: Bagh alley neighborhood of Tabriz. Scientific Journals System, 4 (3): 99-112
6.        Allen, R. G., Tasumi, M., Morse, A., & Trezza, R. (2005). A Landsat-based energy balance and evapotranspiration model in Western US water rights regulation and planning. Irrigation and Drainage systems, 19(3-4), 251-268.
7.        Amiri, R., Weng, Q., Alimohammadi, A., & Alavipanah, S. K. (2009). Spatial–temporal dynamics of land surface temperature in relation to fractional vegetation cover and land use/cover in the Tabriz urban area, Iran. Remote sensing of environment, 113(12), 2606-2617.
8.        Artis, D. A., & Carnahan, W. H. (1982). Survey of emissivity variability in thermography of urban areas. Remote sensing of Environment, 12(4), 313-329.
9.        Atkinson, B. W. (2003). Numerical modelling of urban heat-island intensity. Boundary-Layer Meteorology, 109(3), 285-310.
10.    Bottyán, Z., Kircsi, A., Szegedi, S., & Unger, J. (2005). The relationship between built‐up areas and the spatial development of the mean maximum urban heat island in Debrecen, Hungary. International journal of climatology, 25(3), 405-418.
11.    Comarazamy, D. E., González, J. E., Luvall, J. C., Rickman, D. L., & Mulero, P. J. (2010). A land–atmospheric interaction study in the coastal tropical city of San Juan, Puerto Rico. Earth Interactions, 14(16), 1-24.
12.    Comrie, A. C. (2000). Mapping a wind-modified urban heat island in Tucson, Arizona (with comments on integrating research and undergraduate learning). Bulletin of the American Meteorological Society, 81(10), 2417-2432.
13.    Devanathan, P., & Devanathan, K. (2011). Heat island effects. In Green building with concrete: sustainable design and construction (pp. 175-226). CRC Press Boca Raton, FL.
14.    Feizizadeh, B., & Blaschke, T. (2013). Examining urban heat island relations to land use and air pollution: Multiple endmember spectral mixture analysis for thermal remote sensing. IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 6(3), 1749-1756.
15.    Frey, C. M., Rigo, G., & Parlow, E. (2009). Investigation of the daily Urban Cooling Island (UCI) in two coastal cities in an arid environment: Dubai and Abu Dhabi (UAE). City, 81(2.06).
16.    Gaffin, S. R., Rosenzweig, C., Khanbilvardi, R., Parshall, L., Mahani, S., Glickman, H., ... & Hillel, D. (2008). Variations in New York city’s urban heat island strength over time and space. Theoretical and applied climatology, 94(1-2), 1-11.
17.    Gallo, K. P., McNab, A. L., Karl, T. R., Brown, J. F., Hood, J. J., & Tarpley, J. D. (1993). The use of a vegetation index for assessment of the urban heat island effect. Remote Sensing, 14(11), 2223-2230.
18.    Gartland, L. M. (2012). Heat islands: understanding and mitigating heat in urban areas. Routledge.
19.    Ghasemi, H., Artidar, R., Mahmoudian, A. A., Hooshmandifini, Gh. (2005), A Look at Tehran from the Beginning to the Present, Tehran: Institute of Geography and Cartography of Geology, First Edition.
1.        Ghobadi, A., Khosravi, M., & Tavousi, T. (2018). Surveying of heat waves impact on the urban heat islands: Case study, the Karaj City in Iran. Urban climate, 24, 600-615.
20.    Givoni, B. (1991). Impact of planted areas on urban environmental quality: a review. Atmospheric Environment. Part B. Urban Atmosphere, 25(3), 289-299.
21.    Gonsamo, A., Chen, J. M., & Lombardozzi, D. (2016). Global vegetation productivity response to climatic oscillations during the satellite era. Global change biology, 22(10), 3414-3426.
22.    Goward, S. N. (1981). Thermal behavior of urban landscapes and the urban heat island. Physical Geography, 2(1), 19-33.
23.    Guo, G., Wu, Z., Xiao, R., Chen, Y., Liu, X., & Zhang, X. (2015). Impacts of urban biophysical composition on land surface temperature in urban heat island clusters. Landscape and Urban Planning, 135, 1-10.
24.    Gupta, R. P. (2003). Interpretation of data in the thermal infrared region. In Remote Sensing Geology (pp. 183-216). Springer, Berlin, Heidelberg.
25.    Hart, P. S., & Feldman, L. (2018). Would it be better to not talk about climate change? The impact of climate change and air pollution frames on support for regulating power plant emissions. Journal of Environmental Psychology, 60, 1-8.
26.    Hidalgo, J., Masson, V., & Gimeno, L. (2010). Scaling the daytime urban heat island and urban-breeze circulation. Journal of Applied Meteorology and Climatology, 49(5), 889-901.
27.    Jiang, J., & Tian, G. (2010). Analysis of the impact of land use/land cover change on land surface temperature with remote sensing. Procedia environmental sciences, 2, 571-575.
28.    Jones, P. D., & Lister, D. H. (2009). The urban heat island in Central London and urban‐related warming trends in Central London since 1900. Weather, 64(12), 323-327.
29.    Khandelwal, S., Goyal, R., Kaul, N., & Mathew, A. (2018). Assessment of land surface temperature variation due to change in elevation of area surrounding Jaipur, India. The Egyptian Journal of Remote Sensing and Space Science, 21(1), 87-94.
30.    Khosravi, M., Ghobadi, A. (1390). Explaining the Position of Green Roof System in Urban Thermal Island Modulation (Case Study: Karaj), Bi-Quarterly Journal of Urban Ecology Research, 2 (4), 67-78
31.    Kim, Y. H., & Baik, J. J. (2002). Maximum urban heat island intensity in Seoul. Journal of applied meteorology, 41(6), 651-659.
32.    Kuttler, W., & Wienert, U. (2005). The dependence of the urban heat island intensity on latitude-A statistical approach.
33.    Levallius, J. (2005). Green roofs on municipal buildings in Lund: Modeling potential environmental benefits. Lunds universitets Naturgeografiska institution-Seminarieuppsatser.
34.    Liu, L., & Zhang, Y. (2011). Urban heat island analysis using the Landsat TM data and ASTER data: A case study in Hong Kong. Remote Sensing, 3(7), 1535-1552.
35.    Malekpour, P., Talei, M. (2011), modeling the relationship between land use-land cover and surface temperature, using ASTER sensor data. 37 (58), 29-42.
36.    Moreno‐garcia, M. C. (1994). Intensity and form of the urban heat island in Barcelona. International Journal of Climatology, 14(6), 705-710.
37.    Nazarian, A., Ziaian, A., Firoozabadi, P., Jangi, A. 2007, Investigation of the role of location and morphology in the quality of Tehran's air city using GIS RS satellite data, Geographical Research, No. 61.
38.    Oke, T. R. (1973). City size and the urban heat island. Atmospheric Environment (1967), 7(8), 769-779.
2.        Oke, T. R. (1982). The energetic basis of the urban heat island. Quarterly Journal of the Royal Meteorological Society, 108(455), 1-24
39.    Oke, T. R. (1995). The heat island of the urban boundary layer: characteristics, causes and effects. In Wind climate in cities (pp. 81-107). Springer, Dordrecht.
40.    Rajeshwari, A., & Mani, N. D. (2014). Estimation of land surface temperature of Dindigul district using Landsat 8 data. International Journal of Research in Engineering and Technology, 3(5), 122-126.
41.    Ramezani, B., daughter of Mohammad, M. 2010, Recognition of the Middle Range of Heat Island Formation in Rasht, Zagros Vision Geographical Quarterly, Second Year, No. 1.
42.    Ranjbar Saadat abadi, A. (2005), A Case Study of Tehran Heat Island and Its Numerical Simulation, Earth and Space Physics Journal, Volume 1, Issue 31, pp. 63-78.
43.    Rozenstein, O., Qin, Z., Derimian, Y., & Karnieli, A. (2014). Derivation of land surface temperature for Landsat-8 TIRS using a split window algorithm. Sensors, 14(4), 5768-5780.
44.    Schott, J. R., & Volchok, W. J. (1985). Thematic Mapper thermal infrared calibration. Photogrammetric Engineering and Remote Sensing, 51(9), 1351-1357.
45.    Senanayake, I. P., Welivitiya, W. D. D. P., & Nadeeka, P. M. (2013). Urban green spaces analysis for development planning in Colombo, Sri Lanka, utilizing THEOS satellite imagery–A remote sensing and GIS approach. Urban forestry & urban greening, 12(3), 307-314.
46.    Shakiba, A., Ziaeian Firoozabadi, P., Ashourloo, D., Namdari., S. (2009), Analysis of land use relationship and land cover and heat islands in Tehran using ETM + data. Remote Sensing and GIS Iran, 1 (1), 39-56.
47.    Shirvani Moghadam, S., Saeedi Mofrad, S. 1397, Measuring the Effect of Spatial Distribution of Population on Urban Climate Change with Emphasis on Thermal Islands, 6 (1), 79-88.
48.    Streutker, D. R. (2003). Satellite-measured growth of the urban heat island of Houston, Texas. Remote Sensing of Environment, 85(3), 282-289.
49.    Tan, J., Zheng, Y., Tang, X., Guo, C., Li, L., Song, G., ... & Chen, H. (2010). The urban heat island and its impact on heat waves and human health in Shanghai. International journal of biometeorology, 54(1), 75-84.
50.    Tewari, S., Kulhavy, J., Rock, B. N., & Hadas, P. (2003). Remote monitoring of forest response to changed soil moisture regime due to river regulation. Journal of forest science, 49(9), 429-438.
51.    Torok, S. J., Morris, C. J., Skinner, C., & Plummer, N. (2001). Urban heat island features of southeast Australian towns. Australian Meteorological Magazine, 50(1), 1-13.
52.    Tsou, J., Zhuang, J., Li, Y., & Zhang, Y. (2017). Urban heat island assessment using the Landsat 8 data: a case study in Shenzhen and Hong Kong. Urban Science, 1(1), 10.
53.    Turner, D. P., Cohen, W. B., Kennedy, R. E., Fassnacht, K. S., & Briggs, J. M. (1999). Relationships between leaf area index and Landsat TM spectral vegetation indices across three temperate zone sites. Remote sensing of environment, 70(1), 52-68.
54.    Umar, U. M., & Kumar, J. S. (2014). Spatial and temporal changes of urban heat island in Kano Metropolis, Nigeria. Int J Res Eng Sci Technol, 1, 1-9.
55.    Wang, J., Huang, B., Fu, D., Atkinson, P. M., & Zhang, X. (2016). Response of urban heat island to future urban expansion over the Beijing–Tianjin–Hebei metropolitan area. Applied Geography, 70, 26-36.
56.    Weng, Q. (2001). A remote sensing? GIS evaluation of urban expansion and its impact on surface temperature in the Zhujiang Delta, China. International journal of remote sensing, 22(10), 1999-2014.
57.    Weng, Q., Lu, D., & Schubring, J. (2004). Estimation of land surface temperature–vegetation abundance relationship for urban heat island studies. Remote sensing of Environment, 89(4), 467-483.
58.    Wong, N. H., & Yu, C. (2005). Study of green areas and urban heat island in a tropical city. Habitat international, 29(3), 547-558.
59.    Xian, G., & Crane, M. (2006). An analysis of urban thermal characteristics and associated land cover in Tampa Bay and Las Vegas using Landsat satellite data. Remote Sensing of environment, 104(2), 147-156.
60.    Xu, D., & Guo, X. (2014). Compare NDVI extracted from Landsat 8 imagery with that from Landsat 7 imagery. American Journal of Remote Sensing, 2(2), 10-14.
Journal of Climate Research
Volume 1405, Issue 17 - Serial Number 65
Vol. 17, No. 65, Spring 2026
Spring 2026
Pages 105-120