title: A rasterized numerical model of outdoor thermal climate simulation for strategic urban planning based on Geographic Information System (GIS)
Creators: name: Wang, Wenbo
Publisher: name: University of Reading
Year: 2023

description: A consequence of the rapid urbanization process around the world has been the 
deterioration of the urban environment caused by climate change, air pollution, the 
increasing demand for energy, etc. Numerical models can assist sustainable urban 
environmental planning and strategic solutions. This thesis documents a series of 
developments aimed at improving the practicality and ability of climate models to 
assess and optimize urban planning using outdoor thermal climate simulations 
based on a Geographic Information System (GIS). The research focuses on 
efficiently representing the physical and behavioural processes of heat exchange at 
the neighbourhood scale.
Major contributions and key findings include:
1) A new urban surface feature description scheme based on raster data was 
developed. By integrating the representation of urban surface properties into a 
multi-band raster dataset, the new scheme can more briefly and 
comprehensively reflect the morphological features of urban surfaces. It can 
also use map algebra algorithms integrated into climate simulation models to 
reduce computational expense. Also, the input data acquisition method to 
describe the urban surface features has been improved by combining it with the
multi-data source fusion method. Improvements have been made to the pre-processing of input data for urban climate simulations.
2) A new scheme for simulating surface thermal radiation interactions based on a 
2.5D urban structure model was developed. The scheme provides additional 
façade information for the 2.5D building model by the gradient analysis of 
raster data. This makes up for the lack of vertical surface results when analysing 
solar radiation distribution in traditional 2.5D models. The algorithm for 
calculating the solar radiation distribution within districts based on the 2.5D 
model has been improved.
3) A new numerical simulation framework for neighbourhood thermal climates 
using the GIS spatial analysis method was developed. The new framework
includes important urban surface energy transfer processes, as well as new 
algorithms based on geographic information system spatial analysis. The 
framework integrates the raster data map algebra algorithm as the main body 
to simulate the energy exchange process at the urban neighbourhood scale and 
realizes a novel wind direction judgment in a short time with the help of the 
raster data flow direction algorithm. The new framework has been evaluated 
and compared with experimental data to confirm that it can accurately and 
quickly represent the outdoor thermal environment of different urban 
morphologies.
These developments are compiled into a free open-source model using the Python 
language. The integrated model tool has the ability to efficiently quantify 
neighbourhood thermal climate values under different urban morphologies during 
the planning stage. The outputs should help improve urban environmental design 
solutions and promote sustainable urban development.