Urban Thermal Radiant Environment and Heat Stress

  • Feng YangEmail author
  • Liang Chen
Part of the The Urban Book Series book series (UBS)


Study intent This chapter discusses the impact of high-density urban form on the urban thermal environment from a human perspective: the heat stress. In contrast to the air temperature aspect that is normally investigated, the thermal radiant environment of urban settings is examined and the effective indicator of the mean radiant temperature (Tmrt) is used to characterize the urban thermal radiant environment and assess outdoor thermal comfort and heat stress. Two different urban settings with different building geometry and vegetation cover in downtown Shanghai were used as case study sites. A typical heat wave day in 2013 was selected to investigate the daytime radiant heat stress intensity. A GIS-based numerical simulation approach is used and the Solar and Longwave Environmental Irradiance Geometry (SOLWEIG) model was employed to investigate the spatial variation of Tmrt. Spatial analysis modules were developed and the Radiant Heat Stress Intensity index was defined. Result and discussion The study reveals that in Shanghai, under heat waves, the heat stress induced by the thermal radiant environment is quite severe, with Tmrt commonly well above 60 °C in daytime, and intra-urban Tmrt differences are largely influenced by building density and height, street orientation, and vegetation. Open paved spaces and space near sunlit walls are the places that have the highest Tmrt. In conclusion, the present study shows that the spatial variation of Tmrt can be used to identify thermally vulnerable areas and hotspots in complex urban environment and provide implications for urban design toward the mitigation of heat stress in high-density cities.


  1. Ali-Toudert F, Mayer FH (2007) Effects of asymmetry, galleries, overhanging facades and vegetation on thermal comfort in urban street canyons. Sol Energy 81:742–754CrossRefGoogle Scholar
  2. Andrade H, Alcoforado M-J (2008) Microclimatic variation of thermal comfort in a district of Lisbon (Telheiras) at night. Theoret Appl Climatol 92(3–4):225–237CrossRefGoogle Scholar
  3. Arnfield AJ (2003) Review: two decades of urban climate research: a review of turbulence, exchanges of energy and water, and the urban heat island. Int J Climatol 23:1–26CrossRefGoogle Scholar
  4. BBC (2013) China issues heat alert as ‘hottest july’ hits Shanghai. Retrieved from 2 June 2016
  5. Bruse M, Fleer H (1998) Simulating surface-plant-air interactions inside urban environments with a three-dimensional numerical model. Environ Model Softw 3:373–384CrossRefGoogle Scholar
  6. Chen L, Ng E (2012) Outdoor thermal comfort and outdoor activities: a review of research in the past decade. Cities 29:118–125. Scholar
  7. Chen Y-C, Lin T-P, Matzarakis A (2014) Comparison of mean radiant temperature from field experiment and modelling: a case study in Freiburg, Germany. Theoret Appl Climatol 118:535–551CrossRefGoogle Scholar
  8. Chen L, Yu B, Yang F, Mayer H (2016) Intra-urban differences of mean radiant temperature in different urban settings in Shanghai and implications for heat stress under heat waves: a GIS-based approach. Energy Build 130:829–842. Scholar
  9. Fanger PO (1972) Thermal comfort. Analysis and application in environment engineering. McGraw Hill Book Company, New YorkGoogle Scholar
  10. Gabriel KMA, Endlicher WR (2011) Urban and rural mortality rates during heat waves in Berlin and Brandenburg, Germany. Environ Pollut 159:2044–2050CrossRefGoogle Scholar
  11. Gehl J (2011) Life between buildings: using public space, 6th edn. Island PressGoogle Scholar
  12. Goggins WB, Chan EYY, Ng E, Ren C, Chen L (2012) Effect modification of the association between short-term meteorological factors and mortality by urban heat islands in Hong Kong. Plos One 7:e38551CrossRefGoogle Scholar
  13. Höppe P (1992) A new procedure to determine the mean radiant temperature outdoors (in German). Wetter und Leben 44:147–151Google Scholar
  14. Hajat S, O’Connor M, Kosatsky T (2010) Health effects of hot weather: from awareness of risk factors to effective health protection. Lancet 375:856–863CrossRefGoogle Scholar
  15. Huang Y, Yu B, Zhou J, Hu C, Tan W, Hu Z, Wu J (2013) Toward automatic estimation of urban green volume using airborne LiDAR data and high resolution remote sensing images. Frontiers of Earth Science 7(1):43–54CrossRefGoogle Scholar
  16. Kántor N, Unger J (2011) The most problematic variable in the course of human-biometeorological comfort assessment—the mean radiant temperature. Cent Eur J Geosci 3(1):90–110Google Scholar
  17. Lau KK-L, Lindberg F, Rayner D, Thorsson S (2015) The effect of urban geometry on mean radiant temperature under future climate change: a study of three European cities. Int J Biometeorol 59(7):799–814CrossRefGoogle Scholar
  18. Lau KK-L, Ren C, Ho J, Ng E (2016) Numerical modelling of mean radiant temperature in high-density sub-tropical urban environment. Energy Build 114:80–86CrossRefGoogle Scholar
  19. Lindberg F, Grimmond CSB (2011) The influence of vegetation and building morphology on shadow patterns and mean radiant temperatures in urban areas: model development and evaluation. Theoret Appl Climatol 105:311–323. Scholar
  20. Lindberg F, Holmer B, Thorsson S (2008) SOLWEIG 1.0—modelling spatial variations of 3D radiant fluxes and mean radiant temperature in complex urban settings. Int J Biometeorol 52(7):697–713Google Scholar
  21. Lindberg F, Onomura S, Grimmond CSB (2016) Influence of ground surface characteristics on the mean radiant temperature in urban areas. Int J Biometeorol. (in press)CrossRefGoogle Scholar
  22. Matzarakis A, Rutz F, Mayer H (2007) Modelling radiation fluxes in simple and complex environments—application of the RayMan model. Int J Biometeorol 51(4):323–334CrossRefGoogle Scholar
  23. Mayer H, Höppe P (1987) Thermal comfort of man in different urban environments. Theoret Appl Climatol 38:43–49CrossRefGoogle Scholar
  24. Shanghai Daily (2013) An official 40.6 °C makes it another record day for city. Retrieved from 2 June 2016
  25. Stewart I (2011) A systematic review and scientific critique of methodology in modern urban heat island literature. Int J Climatol 31:200–217CrossRefGoogle Scholar
  26. Takebayashi H, Moriyama M (2007) Surface heat budget on green roof and high reflection roof for mitigation of urban heat island. Build Environ 42:2971–2979CrossRefGoogle Scholar
  27. Tan Z, Lau KK-L, Ng E (2016) Urban tree design approaches for mitigating daytime urban heat island effects in a high-density urban environment. Energy Build 114:265–274CrossRefGoogle Scholar
  28. Thorsson S, Lindberg F, Björklund J, Holmer B, Rayner D (2011) Potential changes in outdoor thermal comfort conditions in Gothenburg, Sweden due to climate change: the influence of urban geometry. Int J Climatol 31:324–335CrossRefGoogle Scholar
  29. Thorsson S, Lindberg F, Holmer B, Eliasson I (2007) Different methods for estimating the mean radiant temperature in an outdoor urban setting. Int J Climatol 27(14):1983–1993CrossRefGoogle Scholar
  30. Thorsson S, Rocklöv J, Konarska J, Lindberg F, Holmer B, Dousset B, Rayne D (2014) Mean radiant temperature—a predictor of heat related mortality. Urb Clim 10(2):332–345CrossRefGoogle Scholar
  31. Wang Y, Berardi U, Akbari H (2016) Comparing the effects of urban heat island mitigation strategies for Toronto, Canada. Energy Build 114:2–19CrossRefGoogle Scholar

Copyright information

© Springer Nature Singapore Pte Ltd. 2020

Authors and Affiliations

  1. 1.College of Architecture and Urban PlanningTongji UniversityShanghaiChina
  2. 2.School of Geographic SciencesEast China Normal UniversityShanghaiChina

Personalised recommendations