Greenbelt GIS Consulting

Summary
    Greenbelt GIS Consulting has been tasked by the City of Austin Urban Forestry Program to analyze the effectiveness of the NeighborWoods tree planting program in mitigating the Urban Heat Island (UHI) effect. The NeighborWoods tree planting program is a joint initiative combing forces between the City of Austin Urban Forestry Department, Austin Energy, and TreeFolks, a nonprofit organization. The program hopes to improve Austin through the environmental benefits of trees, which include reduction of energy consumption, managing storm water, and mitigating the UHI effect.

Purpose
    Mitigation of the UHI effect is a key benefit of trees; however, tree planting programs are rarely analyzed for these factors. By using the locations of the NeighborWoods tree planting locations, Greenbelt GIS Consulting will use ERDAS temperature data and ArcGIS to analyze temperatures in Austin since 2002. By comparing locations with these tree planting locations and locations without them, we can understand how well these trees mitigate and reduce the UHI effect in Austin, Texas.

Methods
    In order to complete this study, Greenbelt GIS Consulting used GIS to analyze tree planting locations, and ERDAS to remotely sense surface temperature, in order determine the cooling and other mitigating effects of trees. In ArcGIS, we conducted a series of three maps-2002, 2009, and 2014. These maps show both the surface temperature and tree plantings locations for the aforementioned times. By determining the mean surface temperature per zip code in the study area, we understood the differences in temperature while accounting for tree density. These differences were then tested for statistical significance using the Wilcoxon Signed Rank Test. To complete the study, we analyzed energy reduction benefits of NeighborWoods trees using the Tree Benefit calculator.

Conclusion
    This study serves the NeighborWoods tree planting program by helping prove its effectiveness and positive effects for the City of Austin. As Austin grows in population, the tendency will be to increase in temperature and UHI effect. By using the NeighborWoods tree program, these negative effects of growth can be mitigated and Austin can enjoy the benefits of growth and a healthy environment for all.