Estimation of the wet bulb globe temperature from temperature and relative humidity gradients

Osvaldo Borges Pinto Junior, Sérgio Wagner Gripp Silveira, Carlo Ralph De Musis, Luiz de Annunciação, Osvaldo Alves Pereira


In this study, maps of the estimated heat index for a preservation area in the city of Cuiabá, Mato Grosso, Brazil, were constructed using temperature and relative humidity gradients. Understanding microclimate variable behavior is useful for explaining the relationship between urban sprawl and increased environmental distress. The implementation and preservation of green areas is one way to mitigate the environmental impacts of human activities. Urban parks are one common type of green area in cities. According to ISO 7243, heat exposure can be assessed using the Wet Bulb Globe Temperature (WBGT). This study used multivariate statistical techniques and ordinary kriging to produce a WBGT map of the park during the dry and rainy seasons. Places with heat or freshness islands were identified. Locations along hiking trails and areas with exercise equipment were analyzed for WBGT tendencies in order to propose precautionary heat exposure measures.


Green areas; Urban parks; Heat index; Heat island; Freshness island

Full Text:



AIROLA, A.; PAHIKKALA, T.; WAEGEMAN, W.; DE BAETS, B.; SALAKOSKI, T. An experimental comparison of cross-validation techniques for estimating the area under the ROC curve. Computational Statistics & Data Analysis, V. 55, Issue 4, 2011, P. 1828-1844.

ALI, J. M.; MARSH, S. H.; SMITH, M. J. Modelling the spatiotemporal change of canopy urban heat islands. Building and Environment, V. 107, 2016, P. 64-78.

BUDD, G. Wet-bulb globe temperature (WBGT) — its history and its limitations. Journal of Science and Medicine in Sport, 2008, v. 11, 20-32.

ISO 7243. Hot enviroments estimation of the heat stress on working man, based on the WBGT index (wet bulb globe temperature). International Organization for Standardization, Geneva, 1989.

JEONG, M.; PARKA, S.; SONG, G. Comparison of human thermal responses between the urban forest area and the central building district in Seoul, Korea. Urban Forestry & Urban Greening, V. 15, 2016, P. 133-148.

LIU, L.; LIN, Y.; WANG, D.; LIU, J. An improved temporal correction method for mobile measurement of outdoor thermal climates. Theoretical and Applied Climatology, 2016, p. 1-12.

MAYER, H.; HÖPPE, P. Thermal comfort of man in different urban environments, Theor. Appl. Climatol. 38, v. 1, 1987, 43-49.

OHASHI, Y.; KIKEGAWA, Y; IHARA, SUGIYAMA, T. Numerical simulations of outdoor heat stress index and heat disorder risk in the 23 wards of Tokyo, J. Appl. Meteorol. Climatol. 53 (2014) 583–597.

PARSONS, K. Heat stress standard ISO 7243 and its global application, Ind. Health, V. 44, v. 3, 2006, 368-379.

ROSHAN, G. R.; GHANGHERMEH, A. A.; ATTIA, S. Determining new threshold temperatures for cooling and

heating degree day index of different climatic zones of Iran. Renewable Energy, V. 101, 2017, P. 156-167.

SUGAWARA, H.; SHIMIZU, S.; TAKAHASHI, H.; HAGIWARA, S.; NARITA, K.; MIKAMI, T.; HIRANO, T. Thermal Influence of a Large Green Space on a Hot Urban Environment. J. Environ. Qual. ,45:125-133, 2016.

TAN, K. C.; LIM, H. S.; JAFRI, M. Z. M. Prediction of column ozone concentrations using multiple regression analysis and principal component analysis techniques: A case study in peninsular Malaysia. Atmospheric Pollution Research, V. 7, Issue 3, 2016, P. 533-546.

VILANOVA, S.R.F; CHICHORRO, J. F. Cerrado: aspectos Florísticos e estruturais. IN: GUARIM, V.L.M.S.;

VILANOVA, S.R.F. (Orgs.). Parque da cidade: aspectos socioambientais: Mãe Bonifácia. Cuiabá: EdUFMT, 2014. 133 p.

WANG, Y.; DE GROOT, R.; BAKKER, F.; WÖRTCHE, H.; LEEMANS, R. Thermal comfort in urban green spaces: a survey on a Dutch university campus. Int J Biometeorol, 2016.

ZHENG, S.; ZHAO, L.; LI, Q. Numerical simulation of the impact of different vegetation species on the outdoor thermal environment. Urban Forestry & Urban Greening, V. 18, 2016, P. 138-150.


Copyright (c) 2018 Ciência e Natura

Creative Commons License

This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.