Trees serve as a natural umbrella to mitigate insolation absorbed by features of the urban environment, especially building structures and pavements. For a desert community, trees are a particularly valuable asset because they contribute to energy conservation efforts, improve home values, allow for cost savings, and promote enhanced health and well-being. The main obstacle in creating a sustainable urban community in a desert city with trees is the scarceness and cost of irrigation water. Thus, strategically located and arranged desert trees with the fewest tree numbers possible potentially translate into significant energy, water and long-term cost savings as well as conservation, economic, and health benefits. The objective of this dissertation is to achieve this research goal with integrated methods from both theoretical and empirical perspectives.

This dissertation includes three main parts. The first part proposes a spatial optimization method to optimize the tree locations with the objective to maximize shade coverage on building facades and open structures and minimize shade coverage on building rooftops in a 3-dimensional environment. Second, an outdoor urban physical scale model with field measurement is presented to understand the cooling and locational benefits of tree shade. The third part implements a microclimate numerical simulation model to analyze how the specific tree locations and arrangements influence outdoor microclimates and improve human thermal comfort. These three parts of the dissertation attempt to fill the research gap of how to strategically locate trees at the building to neighborhood scale, and quantifying the impact of such arrangements.

Results highlight the significance of arranging residential shade trees across different geographical scales. In both the building and neighborhood scales, research results recommend that trees should be arranged in the central part of the building south front yard. More cooling benefits are provided to the building structures and outdoor microclimates with a cluster tree arrangement without canopy overlap; however, if residents are interested in creating a better outdoor thermal environment, open space between trees is needed to enhance the wind environment for better human thermal comfort. Considering the rapid urbanization process, limited water resources supply, and the severe heat stress in the urban areas, judicious design and planning of trees is of increasing importance for improving the life quality and sustaining the urban environment.

Background: Household activities are responsible for up to 80% of direct and indirect greenhouse gas emissions in the United States. These greenhouse gas emissions come from activities including actions taken in relation to food, energy, and water (FEW) resource consumption. Therefore, actions taken at a household level have the potential to significantly reduce greenhouse gas emissions. A game-based learning approach can be used to educate youth on what actions they can take around their household to reduce their carbon footprint. <br/>Aim: FEWS for change is a first player role-playing game developed to educate high school students on how their actions impact the FEW resources and carbon emissions. The game also aims to measure how player’s beliefs and worldview effect their game play regarding sustainability and the environment. <br/>Methods: We developed the FEWS (Food, Energy, and Water Systems) for Change role-playing game based on transdisciplinary research of the food, energy, and water nexus, social, economic, and environmental factors. We piloted the game with a few students for initial results and will have a high school classroom pilot the game in mid-May.<br/>Preliminary Results: Results from the 4 participants demonstrated achievement of the learning goal of the pilot testing. This is objective was met by measuring the players improvement on the postsurvey compared to the presurvey. Due to limitations of time and virtual facilitation of this game, the other two learning objectives could not be measured in this initial pilot because not all post-game activities were included which are needed to measure the other learning objectives. When the game is piloted in mid-May, the other two learning objectives will be tested and measured.