Exploring the relationships between vegetation measurements and temperature in residential areas by integrating LIDAR and remotely sensed imagery

摘要

Population growth and urban sprawl have contributed to the formation ofsignificant urban heat island phenomena in Houston, Texas, the fourth largest city in theUnited States. The population growth in Houston was 25.8% between 1990 and 2000nearly double the national average. The demand for information concerning the effectsof urban and suburban development is growing. Houston is currently the only major UScity lacking any kind of comprehensive city zoning ordinances.The Normalized Difference Vegetation Index (NDVI) has been used as asurrogate variable to estimate land surface temperatures at higher spatial resolutions,given the fact that a high-resolution remotely sensed NDVI can be created almosteffortlessly and remotely sensed thermal data at higher resolutions is much moredifficult to obtain. This has allowed researchers to study urban heat island dynamics at amicro-scale. However, this study suggests that a vegetation index alone might not be thebest surrogate variable for providing information regarding the independent effects andlevel of contribution that tree canopy, grass, and low-lying plants have on surfacetemperatures in residential neighborhoods. This research combines LIDAR (LightDetection and Ranging) feature height data and high-resolution infrared aerial photos to measure the characteristics of the micro-structure of residential areas (residentialstructure),derives various descriptive vegetation measurement statistics, and correlatesthe spatial distribution of surface temperature to the type and amount of vegetation coverin residential areas. Regression analysis is used to quantify the independent influencethat different residential-structures have on surface temperature. In regard toimplementing changes at a neighborhood level, the descriptive statistics derived forresidential-structure at a micro-scale may provide useful information to decision-makersand may reveal a guide for future developers concerned with mitigating the negativeeffects of urban heat island phenomena.