Articles | Volume 15, issue 3
https://doi.org/10.5194/gmd-15-1107-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/gmd-15-1107-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Locating trees to mitigate outdoor radiant load of humans in urban areas using a metaheuristic hill-climbing algorithm – introducing TreePlanter v1.0
Nils Wallenberg
CORRESPONDING AUTHOR
Department of Earth Sciences, University of Gothenburg, Gothenburg,
413 20, Sweden
Fredrik Lindberg
Department of Earth Sciences, University of Gothenburg, Gothenburg,
413 20, Sweden
David Rayner
Department of Earth Sciences, University of Gothenburg, Gothenburg,
413 20, Sweden
Related authors
Geon Kang, Fredrik Lindberg, Eliott Bridoux, Nils Wallenberg, and Jae-Jin Kim
EGUsphere, https://doi.org/10.5194/egusphere-2026-6123, https://doi.org/10.5194/egusphere-2026-6123, 2026
This preprint is open for discussion and under review for Geoscientific Model Development (GMD).
Short summary
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Urban tree shade is not uniform. We developed SOLWEIG-LEB (Leaf Energy Balance) to trace sunlight through foliage and calculate leaf temperatures and heat exchange. Evaluated with observations from Germany and Sweden, the model improved estimates of pedestrian radiant heat exposure, mainly through better shading representation. It also maps heat and water exchange between leaves and air within tree crowns, linking assessments of human heat exposure and vegetation thermal responses.
Nils Wallenberg, Björn Holmer, Fredrik Lindberg, Jessika Lönn, Erik Maesel, and David Rayner
Geosci. Model Dev., 19, 1321–1336, https://doi.org/10.5194/gmd-19-1321-2026, https://doi.org/10.5194/gmd-19-1321-2026, 2026
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This work presents a method to calculate wall surface temperatures in complex urban areas using a step heating equation based on air temperature and net radiation at the wall surface. Our results show that the step heating approach is fast and accurate, comparable to other more complex methods. This method can potentially be applied in different areas of interest where wall surface temperatures are important, e.g. modeling of outdoor thermal comfort, building energy and urban energy balance.
Geon Kang, Fredrik Lindberg, Eliott Bridoux, Nils Wallenberg, and Jae-Jin Kim
EGUsphere, https://doi.org/10.5194/egusphere-2026-6123, https://doi.org/10.5194/egusphere-2026-6123, 2026
This preprint is open for discussion and under review for Geoscientific Model Development (GMD).
Short summary
Short summary
Urban tree shade is not uniform. We developed SOLWEIG-LEB (Leaf Energy Balance) to trace sunlight through foliage and calculate leaf temperatures and heat exchange. Evaluated with observations from Germany and Sweden, the model improved estimates of pedestrian radiant heat exposure, mainly through better shading representation. It also maps heat and water exchange between leaves and air within tree crowns, linking assessments of human heat exposure and vegetation thermal responses.
Nils Wallenberg, Björn Holmer, Fredrik Lindberg, Jessika Lönn, Erik Maesel, and David Rayner
Geosci. Model Dev., 19, 1321–1336, https://doi.org/10.5194/gmd-19-1321-2026, https://doi.org/10.5194/gmd-19-1321-2026, 2026
Short summary
Short summary
This work presents a method to calculate wall surface temperatures in complex urban areas using a step heating equation based on air temperature and net radiation at the wall surface. Our results show that the step heating approach is fast and accurate, comparable to other more complex methods. This method can potentially be applied in different areas of interest where wall surface temperatures are important, e.g. modeling of outdoor thermal comfort, building energy and urban energy balance.
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Short summary
Exposure to solar radiation on clear and warm days can lead to heat stress and thermal discomfort. This can be alleviated by planting trees providing shade in particularly warm areas. Here, we use a model to locate trees and optimize their blocking of solar radiation. Our results show that locations can differ depending, e.g., tree size (juvenile or mature) and number of trees that are positioned simultaneously. The model is available as a tool for accessibility by researchers and others.
Exposure to solar radiation on clear and warm days can lead to heat stress and thermal...