This repository is supplementary to the paper "Sun, Y., Fu, W., Schultz, D. M., He, C., Tai, A. P. K., Tam, C. Y., & Zheng, Z. (2026). Future atmospheric and urban responses to phased deployment of white roofs in Hong Kong, China."
The objectives of this project are:
- Propose a new evaluation method to specify the implementation pathway using the transient roof albedo representation and WRF-CLMU functionalities;
- Mimic urban adaptive action that increases roof albedo in Hong Kong by 0.025 per month from April to September of 2035-2039 for five years;
- Examine the albedo-induced changes in local climate (urban and rural) and atmosphere.
This study uses WRFv4.7.1 and CTSM5.3.024 in a coupled mode. Files listed below are for CTSM modification:
The figures listed below illustrate previous literature and white roof mechanisms.
| Subject | Visualization |
|---|---|
| Numerical simulations for white roof assessment | Figure |
| Map WRF simulations in journal articles published in 2011-2025 | Figure |
| Illustration of urban and atmospheric responses to white roofs | Figure |
The scripts listed below process output from CNTL (transient_urbanalbedo_roof=.false.) and TranAlbe (transient_urbanalbedo_roof=.true.) simulations and visualize them.
| Num. | Subject | Output data process | Visualization |
|---|---|---|---|
| 3.1 | Urban fraction and roof albedo | Use Export.ipynb to export surface input data | Figure.ipynb |
| 3.2 | Model domains | Not applicable | Figure.ipynb |
| 3.3 | Baseline results | Use Export.ipynb to export results in the CNTL simulation | Figure.ipynb |
| 3.4 | Heatwave metrics | Use Export.ipynb to export heatwave metrics in the CNTL and TranAlbe simulations | Not applicable |
| 3.5 | Human heat stress metrics | Use Export.ipynb to export human heat stress metrics in the CNTL and TranAlbe simulations | Figure.ipynb |
| 3.6 | Building energy metrics | Use Export.ipynb to export air-conditioning and space heating fluxes in the CNTL and TranAlbe simulations | Figure.ipynb |
| 3.7 | Anthropogenic heat | Use Export.ipynb to export anthropogenic heat fluxes in the CNTL and TranAlbe simulations | Not applicable |
| 3.8 | Meteorological variations | Use Export.ipynb to export changes in meteorological variables between the CNTL and TranAlbe simulations | Figure.ipynb |
| 3.9 | Cloud fractions | Use Export.ipynb to export changes in cloud fraction between the CNTL and TranAlbe simulations | Figure.ipynb |
| 3.10 | Urban heat island | Use Export.ipynb to export changes in urban heat island intensity between the CNTL and TranAlbe simulations | Figure.ipynb |
| 3.11 | Urban and rural temperatures | Use Export.ipynb to export changes in urban/rural ground and canopy-air temperatures between the CNTL and TranAlbe simulations | Figure.ipynb |
| 3.12 | Regression | Use Export.ipynb to conduct regressions | Not applicable |
| 3.13 | Morphological impact | Use Export.ipynb to export morphological parameters and temperature reduction | Figure.ipynb |
The auxiliary datasets used for analysis are listed below.
| Num. | Dataset name | Source |
|---|---|---|
| 4.1 | Administrative shapefile | Link |
| 4.2 | Land mask | Not applicable |
| 4.3 | Annual journal publications of WRF simulations with high urban albedo | Not applicable |
| 4.4 | Köppen-Geiger climate zone | Link |
- WRF_high_urban_albedo_2011-2025 lists previous publications (2011-2025) on WRF simulations with high urban albedo.
- This work was supported by the Natural Environment Research Council [grant number UKRI1294].
- The authors appreciate the joint research funding from The University of Manchester and The Chinese University of Hong Kong.
- This work used the ARCHER2 UK National Supercomputing Service and JASMIN, the UK’s collaborative data analysis environment.
- Z.Z. appreciates the support provided by the academic start-up funds from the Department of Earth and Environmental Sciences at The University of Manchester.
- Y.S. is supported by Z.Z.'s academic start-up funds.
- The authors declare no conflict of interest.