Related Experiment Video
Updated: Aug 7, 2026
04:35
Development of an Individual-Tree Basal Area Increment Model using a Linear Mixed-Effects Approach
Published on: July 3, 2020
Increasing Urban Tree Canopy Associated With Reduced Mortality: A Longitudinal Analysis of Chicago Neighborhoods
Harrison C Garcia1,2, Peter M Graffy1,2,3,4, Benjamin W Barrett1,2,3,4
1Feinberg School of Medicine Northwestern University Chicago IL USA.
Geohealth
|August 6, 2026
Summary
Protecting urban tree canopy is vital for reducing mortality. Year-to-year increases in tree cover significantly lower death rates from various diseases, especially in hotter neighborhoods.
Area of Science:
- Environmental Science
- Public Health
- Urban Planning
Background:
- Urban tree canopy (UTC) mitigates heat and improves health, but its long-term effects on mortality alongside temperature are unclear.
- Understanding the interplay between UTC, temperature, and mortality is crucial for urban environmental and health policies.
Purpose of the Study:
- To investigate the longitudinal associations between urban tree canopy, temperature, and all-cause and disease-specific mortality in Chicago.
- To identify disparities in canopy, temperature, and mortality across Chicago's community areas and understand their interactions.
Main Methods:
- Utilized high-resolution data on tree canopy, temperature, mortality, and demographics in Chicago from 2011-2021.
- Employed negative binomial generalized estimating equations to model mortality rates based on UTC cover, changes in UTC, and maximum temperature, adjusting for demographics.
- Applied K-means clustering to identify spatial patterns and disparities in canopy, temperature, and mortality.
Main Results:
- Existing tree canopy coverage was not significantly associated with mortality.
- Each annual percentage increase in tree canopy was linked to a ~10% reduction in overall mortality.
- Significant reductions in mortality were observed for cardiovascular, mental health, musculoskeletal, and respiratory diseases with increased tree canopy.
- Cluster analysis revealed that neighborhoods on Chicago's South and West sides experienced high temperatures, significant canopy loss, and increased mortality.
- In hotter areas, greater year-to-year canopy loss correlated with higher mortality.
Conclusions:
- Year-to-year increases in urban tree canopy, not just existing coverage, are associated with reduced mortality.
- Protecting tree canopy from loss, especially in high-temperature areas, is a critical strategy for mitigating mortality and climate change impacts.
- Targeted urban greening strategies are needed to address disparities and improve public health in vulnerable communities.
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