Effective Street Geometry and Shading Strategies for Pedestrian Thermal Comfort: A Scenario Based Simulation Approach
Abstract
The development of urban heat issues poses significant challenges for pedestrians in tropical cities, necessitating climate-responsive street design. This study employs a scenario-based simulation approach to determine optimal combinations of street geometry and shading strategies that enhance Pedestrian Thermal Comfort (PTC). Using ENVI-met, this study simulated 90 scenarios by combining geometric variables, such as aspect ratio (AR), building typology (BT), and street orientation, with five shading strategies in Nagpur City, India. The modified Physiological Equivalent Temperature (mPET) index was calculated for each scenario using a pre-trained machine learning model. Results quantified that canopy shading was the most effective strategy, reducing mPET by up to 7°C in E-W streets. The effective street geometric combination was a N-S oriented street with a deep AR and linear BT, which consistently achieved the lowest mPET values (33.1–35.8°C). The study concludes with a rating matrix that guides the integration of shading design with street geometry to achieve thermally resilient streets.
References
Abdelhafez, M. H. H., Altaf, F., Alshenaifi, M., Hamdy, O., & Ragab, A. (2022). Achieving Effective Thermal Performance of Street Canyons in Various Climatic Zones. Sustainability, 14(17), 10780–10780. https://doi.org/10.3390/SU141710780
Abdollahzadeh, N., & Biloria, N. (2021). Outdoor thermal comfort: Analyzing the impact of urban configurations on the thermal performance of street canyons in the humid subtropical climate of Sydney. Frontiers of Architectural Research, 10(2), 394–409. https://doi.org/10.1016/J.FOAR.2020.11.006
Achour-Younsi, S., & Kharrat, F. (2016a). Outdoor Thermal Comfort: Impact of the Geometry of an Urban Street Canyon in a Mediterranean Subtropical Climate – Case Study Tunis, Tunisia. Procedia - Social and Behavioral Sciences, 216(October 2015), 689–700. https://doi.org/10.1016/j.sbspro.2015.12.062
Achour-Younsi, S., & Kharrat, F. (2016b). Outdoor Thermal Comfort: Impact of the Geometry of an Urban Street Canyon in a Mediterranean Subtropical Climate – Case Study Tunis, Tunisia. Procedia - Social and Behavioral Sciences, 216, 689–700. https://doi.org/10.1016/J.SBSPRO.2015.12.062
Aghamolaei, R., Azizi, M. M., Aminzadeh, B., & O’Donnell, J. (2023). A comprehensive review of outdoor thermal comfort in urban areas: Effective parameters and approaches. Energy and Environment, 34(6), 2204–2227. https://doi.org/10.1177/0958305X221116176
Aicha, C., Moussadek, B., & Djamila, D. (2022). The Effect of Sky View Factor on the Thermic Ambiances: Case of Batna City. International Journal of Innovative Studies in Sociology and Humanities, 7(8), 209–220. https://doi.org/10.20431/2456-4931.070820
Albdour, M. S., & Baranyai, B. (2019). Impact of street canyon geometry on outdoor thermal comfort and weather parameters in Pécs. Pollack Periodica, 14(3), 177–187. https://doi.org/10.1556/606.2019.14.3.17
Arif, V., & Yola, L. (2020). The Primacy of Microclimate and Thermal Comfort in a Walkability Study in the Tropics: A Review. Journal of Strategic and Global Studies, 3(1). https://doi.org/10.7454/jsgs.v3i1.1025
Arif, V., & Yola, L. (2022). The Impact of Sky View Factor on Pedestrian Thermal Comfort in Tropical Context: A Case of Jakarta Sidewalk. Lecture Notes in Civil Engineering, 161, 27–33. https://doi.org/10.1007/978-981-16-2329-5_4
Armson, D., Stringer, P., & Ennos, A. R. (2012). The effect of tree shade and grass on surface and globe temperatures in an urban area. Urban Forestry & Urban Greening, 11(3), 245–255. https://doi.org/10.1016/J.UFUG.2012.05.002
Battista, G., de Lieto Vollaro, E., Ocłoń, P., & de Lieto Vollaro, R. (2023). Effects of urban heat island mitigation strategies in an urban square: A numerical modelling and experimental investigation. Energy and Buildings, 282, 112809. https://doi.org/10.1016/J.ENBUILD.2023.112809
Bourbia, F., & Awbi, H. B. (2004). Building cluster and shading in urban canyon for hot dry climate Part 2: Shading simulations. Renewable Energy, 29(2), 291–301. https://doi.org/10.1016/S0960-1481(03)00171-X
Chatzidimitriou, A., & Yannas, S. (2017). Street canyon design and improvement potential for urban open spaces; the influence of canyon aspect ratio and orientation on microclimate and outdoor comfort. Sustainable Cities and Society, 33, 85–101. https://doi.org/10.1016/j.scs.2017.05.019
Chen, L., Ng, E., An, X., Ren, C., Lee, M., Wang, U., & He, Z. (2012). Sky view factor analysis of street canyons and its implications for daytime intra-urban air temperature differentials in high-rise, high-density urban areas of Hong Kong: A GIS-based simulation approach. International Journal of Climatology, 32(1), 121–136. https://doi.org/10.1002/joc.2243
De, B., & Mukherjee, M. (2018). “Optimisation of canyon orientation and aspect ratio in warm-humid climate: Case of Rajarhat Newtown, India.” Urban Climate, 24, 887–920. https://doi.org/10.1016/J.UCLIM.2017.11.003
Dunjić, J. (2019). Outdoor Thermal Comfort Research in Urban Areas of Central and Southeast Europe: A Review. Geographica Pannonica, 23(4), 359–373. https://doi.org/10.5937/GP23-24458
Dzyuban, Y., Hondula, D. M., Vanos, J. K., Middel, A., Coseo, P. J., Kuras, E. R., & Redman, C. L. (2022). Evidence of alliesthesia during a neighborhood thermal walk in a hot and dry city. Science of The Total Environment, 834, 155294. https://doi.org/10.1016/J.SCITOTENV.2022.155294
Elnabawi, M. H., Hamza, N., & Dudek, S. (2013). Use and evaluation of the ENVI-met model for two different urban forms in Cairo, Egypt: Measurements and model simulations. Proceedings of Building Simulation 2013: 13th Conference of IBPSA, 13, 2800–2806. https://doi.org/10.26868/25222708.2013.1237
Elrefai, R., & Nikolopoulou, M. (2023). A simplified outdoor shading assessment method (OSAM) to identify outdoor shading requirements over the year within an urban context. Sustainable Cities and Society, 97, 104773. https://doi.org/10.1016/j.scs.2023.104773
Galal, O. M., Sailor, D. J., & Mahmoud, H. (2020). The impact of urban form on outdoor thermal comfort in hot arid environments during daylight hours, case study: New Aswan. Building and Environment, 184, 107222. https://doi.org/10.1016/J.BUILDENV.2020.107222
Glen T. Johnson and Ian Watson. (1984). The determination of view factor in urban canyons. Americal Metrological Society. https://www.ptonline.com/articles/how-to-get-better-mfi-results
Harrington, L. J., Frame, D. J., Fischer, E. M., Hawkins, E., Joshi, M., & Jones, C. D. (2016). Poorest countries experience earlier anthropogenic emergence of daily temperature extremes. Environmental Research Letters, 11(5), 055007. https://doi.org/10.1088/1748-9326/11/5/055007
Hess, J., Meister, A., Melnikov, V. R., & Axhausen, K. W. (2023). Geographic Information System-Based Model of Outdoor Thermal Comfort: Case Study for Zurich. Transportation Research Record, 2677(3), 1465–1480. https://doi.org/10.1177/03611981221125211
ICLEI. (2021). Climate resilient city action plan: Nagpur, Maharashtra, India (Supported and jointly implemented). http://southasia.iclei.org
IPCC. (2022). Climate Change 2022: Impacts, Adaptation and Vulnerability. https://doi.org/ISBN 978-92-9169-161-6
Jamei, E., & Rajagopalan, P. (2017). Urban development and pedestrian thermal comfort in Melbourne. Solar Energy, 144, 681–698. https://doi.org/10.1016/j.solener.2017.01.023
Khaire, J. D., Ortega Madrigal, L., & Serrano Lanzarote, B. (2024). Outdoor thermal comfort in built environment: A review of studies in India. Energy and Buildings, 303, 113758. https://doi.org/10.1016/J.ENBUILD.2023.113758
Kim, Y. J., & Brown, R. D. (2021). A multilevel approach for assessing the effects of microclimatic urban design on pedestrian thermal comfort: The High Line in New York. Building and Environment, 205, 108244. https://doi.org/10.1016/j.buildenv.2021.108244
Konarska, J., Uddling, J., Holmer, B., Lutz, M., Lindberg, F., Pleijel, H., & Thorsson, S. (2016). Transpiration of urban trees and its cooling effect in a high latitude city. International Journal of Biometeorology, 60(1), 159–172. https://doi.org/10.1007/S00484-015-1014-X/FIGURES/8
Kotharkar, R., Bagade, A., & Agrawal, A. (2019). Investigating Local Climate Zones for Outdoor Thermal Comfort Assessment in an Indian City. Geographica Pannonica, 23(4), 318–328. https://doi.org/10.5937/gp23-24251
Kotharkar, R., Dongarsane, P., & Keskar, R. (2023). Determining influence of urban morphology on air temperature and heat index with hourly emphasis. Building and Environment, 233, 110044. https://doi.org/10.1016/j.buildenv.2023.110044
Li, Y., Huang, N., & He, J. (2023). Analytical evaluation of thermal comfort in the pedestrian environment using pedestrian shade space distribution. Urban Climate, 51, 101665. https://doi.org/10.1016/J.UCLIM.2023.101665
Lin, T. P. (2009). Thermal perception, adaptation and attendance in a public square in hot and humid regions. Building and Environment, 44(10), 2017–2026. https://doi.org/10.1016/J.BUILDENV.2009.02.004
Lin, T. P., & Matzarakis, A. (2008). Tourism climate and thermal comfort in Sun Moon Lake, Taiwan. International Journal of Biometeorology, 52(4), 281–290. https://doi.org/10.1007/s00484-007-0122-7
Lin, T. P., Matzarakis, A., & Hwang, R. L. (2010). Shading effect on long-term outdoor thermal comfort. Building and Environment, 45(1), 213–221. https://doi.org/10.1016/j.buildenv.2009.06.002
Lindberg, F., & Grimmond, C. S. B. (2011). The influence of vegetation and building morphology on shadow patterns and mean radiant temperatures in urban areas: Model development and evaluation. Theoretical and Applied Climatology, 105(3), 311–323. https://doi.org/10.1007/S00704-010-0382-8/FIGURES/12
Lobaccaro, G., Acero, J. A., Martinez, G. S., Padro, A., Laburu, T., & Fernandez, G. (2019). Effects of orientations, aspect ratios, pavement materials and vegetation elements on thermal stress inside typical urban canyons. International Journal of Environmental Research and Public Health, 16(19), 3574. https://doi.org/10.3390/ijerph16193574
Ma, X., Zhao, J., Zhang, L., Wang, M., & Cheng, Z. (2020). The Deviation between the Field Measurement and ENVI-met Outputs in Winter- A Cases Study in a Traditional Dwelling Settlement of China. https://doi.org/10.21203/RS.3.RS-94479/V1
Manavvi, S., & Milosevic, D. (2025). Chasing cool: Unveiling the influence of green-blue features on outdoor thermal environment in Roorkee (India). Building and Environment, 267, 112238. https://doi.org/10.1016/J.BUILDENV.2024.112238
Marcotullio, P. J., Keßler, C., Quintero Gonzalez, R., & Schmeltz, M. (2021). Urban Growth and Heat in Tropical Climates. Frontiers in Ecology and Evolution, 9, 616626. https://doi.org/10.3389/FEVO.2021.616626/BIBTEX
Matzarakis, A. (2009). Additional features of the RayMan model. The Seventh International Conference on Urban, July, 3–6. http://www.urbanclimate.net/matzarakis1/papers/ICUC7_rayman_374543-1-090330185705-002.pdf
Matzarakis, A., & Mayer, H. (1996, December). Another kind of environmental stress: Thermal stress. WHO Collaborating Centre for Air Quality Management and Air Pollution Control, Institute for Water, Soil and Air Hygiene – Federal Environmental Agency (Newsletter No. 18).
Meshram, D. S. (2011). Institute of Town Planners. India Journal 8-4, 1–20.
Middel, A., Selover, N., Hagen, B., & Chhetri, N. (2016). Impact of shade on outdoor thermal comfort—a seasonal field study in Tempe, Arizona. International Journal of Biometeorology, 60(12), 1849. https://doi.org/10.1007/S00484-016-1172-5
Mohite, S., & Surawar, M. (2024a). Assessing Pedestrian Thermal Comfort to Improve Walkability in the Urban Tropical Environment of Nagpur City. Geographica Pannonica, 28(1), 71–84. https://doi.org/10.5937/gp28-48166
Mohite, S., & Surawar, M. (2024b). Assessment and prediction of pedestrian thermal comfort through machine learning modelling in tropical urban climate of Nagpur City. Theoretical and Applied Climatology, 2006, 1–23. https://doi.org/10.1007/s00704-024-04967-x
Mohite, S., & Surawar, M. (2024c). Impact of urban street geometry on outdoor pedestrian thermal comfort during heatwave in Nagpur city. Sustainable Cities and Society, 108(April), 105450. https://doi.org/10.1016/j.scs.2024.105450
Paul, T., Daketi, S., Rao, K. M., & Chundeli, F. A. (2025). A qualitative approach for investigating thermal discomfort in the outdoor environment of a World Heritage Site: A case study of Hampi, India. Geographica Pannonica, 29(3), 172–193. https://doi.org/10.5937/gp29-57738
Porwal, S., Mandal, S. K., Banerjee, S., & Abdul, A. P. J. (2025). Factors Influencing Outdoor Thermal Comfort: A Review. International Research Journal of Multidisciplinary Scope (IRJMS), 6(2), 478–487. https://doi.org/10.47857/irjms.2025.v06i02.03123
Qaid, A., & Ossen, D. R. (2015). Effect of asymmetrical street aspect ratios on microclimates in hot, humid regions. International Journal of Biometeorology, 59(6), 657–677. https://doi.org/10.1007/S00484-014-0878-5/FIGURES/15
Raman, V., Kumar, M., Sharma, A., & Matzarakis, A. (2021). A quantitative assessment of the dependence of outdoor thermal-stresses on tree-building morphology and wind: A case-study in sub-tropical Patna, India. Sustainable Cities and Society, 73, 103085. https://doi.org/10.1016/J.SCS.2021.103085
Ratnayake, C. W., Perera, N. G. R., & Emmanuel, R. (2022a). Street Tree Planting Patterns to Modify the Sky View Factor for Outdoor Thermal Comfort Enhancement. FARU Journal, 9(2), 1–1. https://doi.org/10.4038/FARUJ.V9I2.167
Russo, S., Sillmann, J., Sippel, S., Barcikowska, M. J., Ghisetti, C., Smid, M., & O’Neill, B. (2019). Half a degree and rapid socioeconomic development matter for heatwave risk. Nature Communications, 10(1), 1–9. https://doi.org/10.1038/s41467-018-08070-4
Sayad, B., Alkama, D., Ahmad, H., Baili, J., Aljahdaly, N. H., & Menni, Y. (2021). Nature-based solutions to improve the summer thermal comfort outdoors. Case Studies in Thermal Engineering, 28. https://doi.org/10.1016/J.CSITE.2021.101399
Segura, R., Krayenhoff, E. S., Martilli, A., Badia, A., Estruch, C., Ventura, S., & Villalba, G. (2022). How do street trees affect urban temperatures and radiation exchange? Observations and numerical evaluation in a highly compact city. Urban Climate, 46, 101288. https://doi.org/10.1016/J.UCLIM.2022.101288
Sharmin, T., & Steemers, K. (2013). Effect of Canyon Geometry on Outdoor Thermal Comfort. PLEA2013 - 29th International Conference Proceedings: Sustainable Architecture for a Renewable Future, Munich, Germany. 10-12 September 2013, September. https://mediatum.ub.tum.de/doc/1169310/file.pdf
Siqi, J., Yuhong, W., & Nyuk Hien, W. (2023). The effect of urban greening on pedestrian’s thermal comfort and walking behaviour. E3S Web of Conferences, 396. https://doi.org/10.1051/e3sconf/202339605013
Speak, A., Montagnani, L., Wellstein, C., & Zerbe, S. (2020). The influence of tree traits on urban ground surface shade cooling. Landscape and Urban Planning, 197, 103748. https://doi.org/10.1016/J.LANDURBPLAN.2020.103748
Srivanit, M., & Jareemit, D., (2019, December 1). Modelling the Urban Microclimate Effects of Street Configurations on Thermal Environment in the Residential Townhouse of Bangkok, Thailand. 1st International Conference on Recent Advances in Science and Technology (ICORAST 2019), MalaysiaAt: Kuala Lumpur, Malaysia. https://doi.org/10.13140/RG.2.2.17499.21283
Surawar, Meenal; Kotharkar, R. (2017). Assessment of Urban Heat Island through Remote Sensing in Nagpur Urban Area Using Landsat 7 ETM+ satellite images. International Journal of Urban and Civil Enginering, 11(7), 868–874. https://doi.org/10.5281/ZENODO.1131073
Tumini, I., Higueras García, E., & Baereswyl Rada, S. (2016). Urban microclimate and thermal comfort modelling: strategies for urban renovation. International Journal of Sustainable Building Technology and Urban Development, 7(1), 22–37. https://doi.org/10.1080/2093761X.2016.1152204
Vailshery, L. S., Jaganmohan, M., & Nagendra, H. (2013). Effect of street trees on microclimate and air pollution in a tropical city. Urban Forestry & Urban Greening, 12(3), 408–415. https://doi.org/10.1016/J.UFUG.2013.03.002
Vasilikou, C., & Nikolopoulou, M. (2020). Outdoor thermal comfort for pedestrians in movement: thermal walks in complex urban morphology. International Journal of Biometeorology, 64(2), 277–291. https://doi.org/10.1007/s00484-019-01782-2
Watanabe, S., & Ishii, J. (2016). Effect of outdoor thermal environment on pedestrians’ behavior selecting a shaded area in a humid subtropical region. Building and Environment, 95, 32–41. https://doi.org/10.1016/j.buildenv.2015.09.015
Willmott, C. J. (1982). Some comments on the evaluation of model performance. Bulletin - American Meteorological Society, 63(11), 1309–1313. https://doi.org/10.1175/1520-0477(1982)063<1309:SCOTEO>2.0.CO;2
Xu, L., Gopalakrishnan, S., & Schroepfer, T. (2023). Assessment of overhead environments on pedestrian thermal comfort in a dense urban district. https://doi.org/10.1051/e3sconf/202339605012
Yilmaz, S., Kurt, A., & Gölcü, M. (2023). ENVI-met Simulations of the Effect of Different Landscape Design Scenarios on Pedestrian Thermal Comfort: Haydar Aliyev Street. Yuzuncu Yil University Journal of Agricultural Sciences, 33(3), 338–353. https://doi.org/10.29133/yyutbd.1265752
Zhang, M., You, W., Qin, Q., Peng, D., Hu, Y., Gao, Z., & Buccolieri, R. (2022). Investigation of typical residential block typologies and their impact on pedestrian-level microclimate in summers in Nanjing, China. Frontiers of Architectural Research, 11(2), 278–296. https://doi.org/10.1016/J.FOAR.2021.10.008
Zhang, Y., Du, X., & Shi, Y. (2017). Effects of street canyon design on pedestrian thermal comfort in the hot-humid area of China. International Journal of Biometeorology, 61(8), 1421–1432. https://doi.org/10.1007/S00484-017-1320-6
Zhao, H., Zhao, L., Zhai, Y., Jin, L., Meng, Q., Yan, J., Wu, R., & Brown, R. D. (2024). The impact of dynamic thermal experiences on pedestrian thermal comfort: A whole-trip perspective from laboratory studies. Building and Environment, 258, 111599. https://doi.org/10.1016/J.BUILDENV.2024.111599
