High-Resolution Thermal Mapping for Urban Heat Mitigation: Random Forest Downscaling in a Rapid Urbanization Context (Case Study Malang City, Indonesia)
DOI:
10.29303/jppipa.v11i12.13393Published:
2025-12-25Downloads
Abstract
This study aims to enhance the spatial resolution of land surface temperature (LST) mapping in Malang City, Indonesia, and to analyze spatiotemporal urban thermal dynamics associated with rapid urbanization. Landsat 8 OLI/TIRS thermal data were integrated with Sentinel-2 multispectral imagery using a Random Forest (RF)–based downscaling approach to refine LST resolution from 30 m to 10 m. Spectral indices, including NDVI, NDBI, NDWI, and NDMI, were employed as predictor variables, and model performance was evaluated using R² and RMSE metrics, supported by in-situ temperature measurements for validation. The results demonstrate strong downscaling performance, with R² values of 0.8374 (2019), 0.8468 (2022), and 0.7675 (2024), while field validation yielded a correlation coefficient of 0.722 and an RMSE of 4.63°C. Spatial and temporal analyses reveal a significant increase in mean LST from 24.67°C in 2019 to 27.21°C in 2024, indicating accelerated urban warming, particularly during 2022–2024. This warming is closely associated with land-use transformation, increased impervious surfaces, and regional climatic influences. In conclusion, the RF-based downscaling approach effectively captures fine-scale urban thermal heterogeneity and provides reliable high-resolution LST information, supporting urban heat mitigation planning and climate adaptation strategies in rapidly growing tropical cities.
Keywords:
Downscaling Land surface temperature Landsat-8 Random forest Remote sensing Sentinel-2References
Apriana, M., & Syahrani, E. (2022). Land Surface Temperature and its Relationship to Population Density. Journal of Applied Geospatial Information, 6(1), 569–575. https://doi.org/10.30871/jagi.v6i1.1936
Artis, D. A., & Carnahan, W. H. (1982). Survey of emissivity variability in thermography of urban areas. Remote Sensing of Environment, 12(4), 313–329. https://doi.org/10.1016/0034-4257(82)90043-8
Asmaryan, S., Muradyan, V., Medvedev, A., Avetisyan, R., Hovsepyan, A., Khlghatyan, A., & Dell’Acqua, F. (2023). Exploring Very High-Resolution Remote Sensing for Assessing Land Surface Temperature of Different Urban Land Cover Patterns. The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, XLVIII-1/W2-2023, 1847-1852. https://doi.org/10.5194/isprs-archives-xlviii-1-w2-2023-1847-2023
Bahi, H., Bounoua, L., Sabri, A., Bannari, A., Malah, A., & Rhinane, H. (2025). A new thermal fusion method to downscale Land Surface Temperature to finer spatial resolution using Sentinel-MSI and Landsat-OLI/TIRS imagery. Remote Sensing Applications: Society and Environment, 37, 101519. https://doi.org/10.1016/j.rsase.2025.101519
Berliani, R., Rosenberg, A., & Prayoga, D. (2025). Identifikasi suhu permukaan laut pada saat El Niño dan IOD positif 2023 di Perairan Barat Sumatera. Jurnal Kelautan, 9(1), 45–58. https://doi.org/10.21107/jk.v18i1.29100.
Chen, S., Yang, Y., Deng, F., Zhang, Y., Liu, D., Liu, C., & Gao, Z. (2022). A high-resolution monitoring approach of canopy urban heat island using a random forest model and multi-platform observations. Atmospheric Measurement Techniques, 15(3), 735-756. https://doi.org/10.5194/amt-15-735-2022.
Chen, Y., Shan, B., & Yu, X. (2022). Study on the spatial heterogeneity of urban heat islands and influencing factors. Building and Environment, 208(108604). https://doi.org/10.1016/j.buildenv.2021.108596
Cheng, J., Liu, Q., Li, X., Xiao, Q., Liu, Q., & Du, Y. (2008). Correlation-based temperature and emissivity separation algorithm. Science in China Series D: Earth Sciences, 51(3), 357-369. https://doi.org/10.1007/s11430-008-0022-7
Chiueh, Y.-W., Tan, C.-H., & Hsu, H.-Y. (2021). The Value of a Decrease in Temperature by One Degree Celsius of the Regional Microclimate—The Cooling Effect of the Paddy Field. Atmosphere, 12(3), 353. https://doi.org/10.3390/atmos12030353
Dimitrov, S., Iliev, M., Borisova, B., Semerdzhieva, L., & Petrov, S. (2024). A Methodological Framework for High-Resolution Surface Urban Heat Island Mapping: Integration of UAS Remote Sensing, GIS, and the Local Climate Zoning Concept. Remote Sensing, 16(21), 4007. https://doi.org/10.3390/rs16214007
Ding, L., Xiao, X., & Wang, H. (2025). Temporal and spatial variations of urban surface temperature and correlation study of influencing factors. https://doi.org/10.1038/s41598-025-85146-4
Eboy, O. V., & Kemarau, R. A. (2023). Analysis of Extreme Heat Land Surface Temperature at a Tropical City (1988-2022): A Study on the Variability of Hot Spot during El Niño Southern Oscillation (ENSO). Science & Technology Indonesia, 8(3), 388–396. https://doi.org/10.26554/sti.2023.8.3.388-396
Galve, J. M., Sánchez, J. M., García-Santos, V., González-Piqueras, J., Calera, A., & Villodre, J. (2022). Assessment of Land Surface Temperature Estimates from Landsat 8-TIRS in A High-Contrast Semiarid Agroecosystem. Algorithms Intercomparison. Remote Sensing, 14(8), 1843. https://doi.org/10.3390/rs14081843
Gao, B. (1996). NDWI—A normalized difference water index for remote sensing of vegetation liquid water from space. Remote Sensing of Environment, 58(3), 257–266. https://doi.org/10.1016/S0034-4257(96)00067-3
Hasyim, A. W., Sukojo, B. M., Anggraini, I. A., Fatahillah, E. R., & Isdianto, A. (2025). Urban Heat Island Effect and Sustainable Planning: Analysis of Land Surface Temperature and Vegetation in Malang City. International Journal of Sustainable Development and Planning, 20(2), 683–697. https://doi.org/10.18280/ijsdp.200218
Hengl, T., Nussbaum, M., Wright, M. N., Heuvelink, G. B. M., & Gräler, B. (2018). Random forest as a generic framework for predictive modeling of spatial and spatio-temporal variables. PeerJ, 6, e5518. https://doi.org/10.7717/peerj.5518
Hidayati, I. N., Suharyadi, R., & Danoedoro, P. (2019). Environmental quality assessment of urban ecology based on spatial heterogeneity and remote sensing imagery. KnE Social Sciences, 13(1), 363–379. https://doi.org/10.18502/kss.v3i21.4981
Irfeey, A. M. M., Chau, H.-W., Sumaiya, M. M. F., Wai, C. Y., Muttil, N., & Jamei, E. (2023). Sustainable Mitigation Strategies for Urban Heat Island Effects in Urban Areas. Sustainability, 15(14), 10767. https://doi.org/10.3390/su151410767
Isdianto, A., Hasyim, A. W., Sukojo, B. M., Alimuddin, I., Anggraini, I. A., & Fatahillah, E. R. (2025). Integrating Urban Design with Natural Dynamics: Enhancing Ecological Resilience in Malang City over a Decade. International Journal of Sustainable Development and Planning, 20(3), 1061–1075. https://doi.org/10.18280/ijsdp.200313
Jiménez‐Muñoz, J. C., & Sobrino, J. A. (2003). A generalized single‐channel method for retrieving land surface temperature from remote sensing data. Journal of Geophysical Research: Atmospheres, 108(D22). https://doi.org/10.1029/2003JD003480
Kuhn, M., & Johnson, K. (2019). Feature Engineering and Selection. Chapman and Hall/CRC. https://doi.org/10.1201/9781315108230
Liu, P., Huo, H., Guo, L., Leng, P., & He, L. (2022). Temperature/Emissivity Separation of Typical Grassland of Northwestern China Based on Hyper-CAM and Its Potential for Grassland Drought Monitoring. Remote Sensing, 14(19), 4809. https://doi.org/10.3390/rs14194809
Li, J., Yang, Z., Zhao, X., Li, Y., Huang, X., Chen, Y., & Shi, F. (2024). Study of the Correlation between the Urban Wind–Heat Environment and Urban Development Elements in High-Density Urban Areas: A Case Study of Central Shanghai. Buildings, 14(2), 315. https://doi.org/10.3390/buildings14020315
Martinuzzi, S., Ramos‐González, O. M., Muñoz‐Erickson, T. A., Locke, D. H., Lugo, A. E., & Radeloff, V. C. (2018). Vegetation cover in relation to socioeconomic factors in a tropical city assessed from sub‐meter resolution imagery. Ecological Applications, 28(3), 681-693. https://doi.org/10.1002/eap.1673.
Merlin, O., Duchemin, B., Hagolle, O., Jacob, F., Coudert, B., Chehbouni, G., & Kerr, Y. H. (2010). Disaggregation of MODIS surface temperature over an agricultural area using a time series of Formosat-2 images. Remote Sensing of Environment, 114(11), 2500-2512. https://doi.org/10.1016/j.rse.2010.05.025
Onačillová, K., Gallay, M., Paluba, D., Péliová, A., Tokarčík, O., & Laubertová, D. (2022). Combining Landsat 8 and Sentinel-2 Data in Google Earth Engine to Derive Higher Resolution Land Surface Temperature Maps in Urban Environment. Remote Sensing, 14(16), 4076. https://doi.org/10.3390/rs14164076
Peng, Yuan, X., Gao, W., Wang, R., & Chen, W. (2021). Assessment of urban cooling effect based on downscaled land surface temperature: A case study for Fukuoka, Japan. Urban Climate, 36, 100790. https://doi.org/10.1016/j.uclim.2021.100790
Purwantara, S., & Ashari, A. (2025). Spatio-temporal variability of urban surface temperature during COVID-19 pandemic: A study from some selected cities in Indonesia and Singapore. Jurnal Wilayah Dan Lingkungan, 12(3), 279–292. https://doi.org/https://doi.org/10.14710/jwl.12.3.279-292
Rakuasa, H., Sihasale, D. A., & Latue, P. C. (2023). Spatial pattern of changes in land surface temperature of seram island based on google earth engine cloud computing. International Journal of Basic and Applied Science, 12(1), 1–9. https://doi.org/10.35335/ijobas.v12i1.172
Rousse, J. W., Haas, R. H., Schell, J., & Deering, D. W. (1973). Monitoring vegetation systems in the Great Plains with ERTS. Third Earth Resources Technology Satellite-1 Symposium (NASA SP-351), 309–317. Retrieved from https://ntrs.nasa.gov/citations/19740022614
Roy, D., Das, B., Singh, P., Santra, P., Deb, S., Bhattacharya, B. K., Govind, A., Jatav, R., Sethi, D., Ghosh, T., Mukherjee, J., Sehgal, V. K., Jha, P. K., Goroshi, S., Prasad, P. V. V., & Chakraborty, D. (2025). Assessing the accuracy of multi-model approaches for downscaling land surface temperature across diverse agroclimatic zones. Scientific Reports, 15(1), 10824. https://doi.org/10.1038/s41598-025-92135-0
Santamouris, M. (2020). Recent Progress on Urban Overheating and Heat Island Research. Integrated Assessment of The Energy, Environmental, Vulnerability and Health Impact. Synergies with The Global Climate Change. Energy and Buildings, 207, 109482. https://doi.org/10.1016/j.enbuild.2019.109482
Sejati, A. W., Buchori, I., & Rudiarto, I. (2019). The spatio-temporal trends of urban growth and surface urban heat islands over two decades in the Semarang Metropolitan Region. Sustainable Cities and Society, 46. https://doi.org/10.1016/j.scs.2019.101432
Sobrino, J. A., Jiménez‐Muñoz, J. C., Sòria, G., Romaguera, M., Guanter, L., Moreno, J., & Martı́nez, P. (2008). Land Surface Emissivity Retrieval From Different VNIR and TIR Sensors. IEEE Transactions on Geoscience and Remote Sensing, 46(2), 316-327. https://doi.org/10.1109/tgrs.2007.904834
Song, L., Liu, S., Kustas, W. P., Zhou, J., & Ma, Y. (2015). Using the Surface Temperature-Albedo Space to Separate Regional Soil and Vegetation Temperatures from ASTER Data. Remote Sensing, 7(5), 5828-5848. https://doi.org/10.3390/rs70505828
Tesfamariam, S., Govindu, V., & Uncha, A. (2023). Spatio-temporal analysis of urban heat island (UHI) and its effect on urban ecology: The case of Mekelle city, Northern Ethiopia. Heliyon, 9(2). https://doi.org/10.1016/j.heliyon.2023.e13098
Uhrin, A., & Onačillová, K. (2025). Spatiotemporal analysis of land surface temperature and land cover changes in Prešov city using downscaling approach and machine learning algorithms. Environmental Monitoring and Assessment, 197(2), 126. https://doi.org/10.1007/s10661-024-13598-8
Voogt, J. ., & Oke, T. (2003). Thermal remote sensing of urban climates. Remote Sensing of Environment, 86(3), 370–384. https://doi.org/10.1016/S0034-4257(03)00079-8
Yang, L., Cao, Y., Zhu, X., Zeng, S., Yang, G., He, J., & Yang, X. (2014). Land surface temperature retrieval for arid regions based on Landsat-8 TIRS data: a case study in Shihezi, Northwest China. Journal of Arid Land, 6(6), 704-716. https://doi.org/10.1007/s40333-014-0071-z
Zahro, H., Sobirin, S., & Wibowo, A. (2018). Variasi spasiotemporal urban heat island di kawasan perkotaan Yogjakarta tahun 2015-2017. Jurnal Geografi Lingkungan Tropik, 2(1). https://doi.org/10.7454/jglitrop.v2i1.35.
Zang, Y., Huang, G., Liu, W., Chen, L., Wu, D., Wang, C., & Li, J. (2023). Deepurbanmodeller (Dum): A Process-Informed Neural Architecture For High-Precision Urban Surface Temperature Prediction. The International Archives of the Photogrammetry Remote Sensing and Spatial Information Sciences, XLVIII-1/W2-2023, 71-76. https://doi.org/10.5194/isprs-archives-xlviii-1-w2-2023-71-2023.
Zha, Y., Gao, J., & Ni, S. (2003). Use of normalized difference built-up index in automatically mapping urban areas from TM imagery. International Journal of Remote Sensing, 24(3), 583–594. https://doi.org/10.1080/01431160304987
License
Copyright (c) 2025 Nevy Ardianto, Aminudin Afandhi, Abu Bakar Sambah

This work is licensed under a Creative Commons Attribution 4.0 International License.
Authors who publish with Jurnal Penelitian Pendidikan IPA, agree to the following terms:
- Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution 4.0 International License (CC-BY License). This license allows authors to use all articles, data sets, graphics, and appendices in data mining applications, search engines, web sites, blogs, and other platforms by providing an appropriate reference. The journal allows the author(s) to hold the copyright without restrictions and will retain publishing rights without restrictions.
- Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgment of its initial publication in Jurnal Penelitian Pendidikan IPA.
- Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access).






