To assess the residential environmental quality for each state, the following metrics were used: Outdoor air quality, total amount of green space, total tree canopy coverage, total amount of impervious surface cover, and urban tree benefits (such as total amount of carbon stored, total amount of carbon sequestered, and total amount of pollution removed). Eighty percent of the US population currently lives in cities, and that figure is projected to continue to grow (US Census Bureau 2010). Therefore, it is critical to address environmental and human health threats to dense urban centers such as the Urban Heat Island Effect (UHI) and air pollution.
Emissions from heating, cooling, and providing electricity to homes add to ground-level ozone and fine particle pollution (ALA 2016). While the US has made significant progress in reducing the levels of ozone and fine particle pollution in communities, largely as a result of the Clean Air Act of 1970, more than 166 million people still live in areas that report unhealthy levels of one or both pollutants (ALA 2016). From a socio-ecological system standpoint, it is critical that cities increase and manage the existing urban tree canopies and the urban ecosystem as a whole so that a healthy balance can be maintained in the complex urban ecosystem.
It is also important to assess residential environmental quality from an equity standpoint, as it is often minority and low-income populations that are the most negatively impacted by poor air quality and the UHI effect.
Metrics and Data Sources
|Metric Name||Definition||Data Source|
|Ozone Pollution||The total percentage of a state’s population living in an area where the National Ambient Air Standard is met for ozone (0.060-0.075 ppm)||Indiana Department of Environmental Management 2015|
|Fine Particle Pollution||The total percentage of a state’s population living in an area where the National Ambient Air Standard is met for 24-hour PM 2.5 (28-35 (μg/m3) and Annual PM 2.5 (9.6-12.0 (μg/m3)||Indiana Department of Environmental Management 2015|
|Total Green Space||The amount of pervious cover (grass, soil, or tree covered areas) of urban and community land||USDA Forest Service 2009|
|Total Tree Canopy Cover||The amount of tree canopy cover in urban and community land.||USDA Forest Service 2009|
|Total Impervious Surface Cover||Total impervious surface cover of urban and community land||USDA Forest Service 2009|
|Urban Tree Benefits||Total carbon stored, total carbon sequestered, and total pollution removed by urban trees.||USDA Forest Service 2009|
- Indiana has an average score of 5.1 which is ranked as 5th among all ten states examined in the State Sustainability Index. This ranking suggests that Indiana is in the middle range of residential environmental quality compared to the other Midwestern states, Washington, and West Virginia.
- Indiana ranks 1st for the largest percentage of its population living in areas that meet the national ozone standard. This result suggests that Indiana is properly managing its ozone pollution levels in areas where it is monitored.
- Indiana ranks 7th for total tree canopy cover, total carbon stored, total carbon sequestered-suggesting a need for improvement in these areas.
- Ozone and fine particle pollution data collection and pollution levels could improve by increasing the number of monitors throughout the 10 states in areas that were not previously monitored.
- Important for Indiana to increase its efforts towards building a greater urban and community tree canopy cover and total green space to improve environmental and human health.