Note

Need help? Please let us know in the UMEP Community.

5.6. Urban Heat Island: UWG Analyser

Note

This plugin is still experimental. Please report any issues to our code repository.

  • Contributor

    Name

    Institution

    Fredrik Lindberg

    Gothenburg
  • Introduction

    The Urban Weather Generator (UWG) tool is an implementation of the Ladybug application with the same name. The original Urban Weather Generator was developed by Bruno Bueno for his PhD thesis at MIT. Since this time, it has been validated 3 times and has been enhanced by Aiko Nakano. In 2016, Joseph Yang also improved the engine and added a range of building templates. For more detailed information on UWG, follow the links above.

    The UWG Analyser plugin can be used to make basic spatial analysis and plot model results generated by the Urban Weather Generator plugin in UMEP for processing. This plugin is availbe both from UMEP for processing and the regular menu-based UMEP plugin. The plotting capabilities are only available in the latter.

  • Dialog box
    ../_images/UWGAnalyserInterface.jpg

    Fig. 5.7 The dialog for the UWG Analyser in UMEP for processing. Click on image for enlargement.

  • Parameters

    Path to folder where UWG input files are located

    Path that contains .uwg-files generated by UWGPrepare.

    Path to folder where UWG output files are located

    Path that contains files generated by Urban Heat Island: Urban Weather Generator. Only UMEP formatted output can be used here, not epw-files.

    Examine single night

    Tick this in if you want to examine UHI for a specific night.

    Month and day when single night begins

    Specify the single date that should be examined. The nocturnal hours from following day will be included. The date specified must be within the days modelled in UWG.

    Statistic measure

    Choose how UHI should be represented, e.g. mean, max etc.

    Vector polygon grid

    The vectory polygon grid that depicts the modelling area(s). This should be the same polygon layer that was used in UWGPrepare and UWG.

    ID field

    Choose the attribute from the selected polygon layer that was used to separate the different polygon objects from each other in UWGPrepare and UWG.

    Polygon grid irregular (not squared)

    Tick this in if a grid is irregular i.e. not squared and aligned north to south.

    Pixel resolution (m)

    When a irregular grid is used, a pixel resolution in meters must be specified.

    Add results to vector polygon grid attribute table

    Tick this in if you like to add UHI statistics in the attribute table of your polygon grid

    Output raster from statistical analysis

    Specify the location of the geotiff that will be created from the analysis

    Open output file after runing algorithm

    The geotiff generated will be added to your QGIS project
  • Run

    Starts the algorithm.

  • Help

    Link to this manual page.

  • Close

    Closes the plugin.

  • Remarks

    • This is a very simple tool for generating spatial information from the UWG. Another version is planned where you also can plot temporal UHI for a specific grid.

    • In the menu-based UMEP tool there is also possibility to plot time series of urban heat island for specific grids as well as specify spesific days to examine.