Examining the Impact of Spatial Development Patterns on Regional Heat Island Effect in Metropolitan Regions of the United States

The urban heat island effect is considered one of the main causes of global warming and is contributing to increasing temperatures in the urban United States. This phenomenon enhances the intensity of summer heat waves and the risk to public health due to increased exposure to extreme thermal conditions.

Characteristics of spatial development patterns can significantly affect urban temperature because they are related to the arrangement of development and land surface materials, which are crucial elements needed to determine land surface temperature. While previous studies revealed that the effect of the urban heat island varies depending on different land use types and surface characteristics, few have considered the overall development patterns of urban form. I address this under-studied aspect of heat hazards by analyzing the relationship between spatial development pattern and urban heat island effect across a sample of 353 metropolitan regions of the U.S. Specifically, I employ a series of landscape metrics to measure urban development patterns using a national land cover dataset from the U.S. Geological Survey. Linear regression models are used to statistically isolate the effect of different spatial development patterns on increasing the urban heat island effect while controlling for multiple contextual variables including built-environment, environmental, and demographic characteristics.

The result of this study showed that the daytime mean surface urban heat island effect (4.04?F) is higher than that of nighttime (2.41?F). Ecological context (i.e. Ecoregions) has proved to be a statistically significant modulator that helps to explain the spatial distribution of the urban heat island effect.

Regarding the main research question of this study, the results indicate that specific categories of urban development pattern including density, continuity, and clustering are statistically associated with increasing the urban heat island effect. This initial evidence suggests that the overall development patterns are an important issue to consider when mitigating the adverse impacts related to the urban heat island effect. In addition, when contextual heat contributors are held constant, the intensity of the urban heat island effect can differ depending on the configuration of development in urban areas.

This study can be used as a starting point for a comprehensive approach to both spatial land development and hazard-resistant planning by providing alternative ways of measuring and modeling spatial development patterns.