# Modeling the effect of temperature on ozone-related mortality

**Authors:** Ander Wilson, Ana G. Rappold, Lucas M. Neas, Brian J. Reich  
**arXiv:** [1412.1642](https://arxiv.org/abs/1412.1642)  
**Date:** 2014-12-04  
**Summary page:** https://www.summarizepaper.com/en/arxiv-id/1412.1642v1/

## Key points

- Climate change is a pressing issue with far-reaching consequences for public health.
- Changes in ambient ozone levels and temperatures are one of the ways in which climate change affects human health.
- Joint effects of ozone and temperature on mortality and morbidity are not well known.
- Ander Wilson, Ana G. Rappold, Lucas M. Neas, and Brian J. Reich propose a spatial, semi-parametric model to estimate the joint ozone-temperature risk surfaces in 95 US urban areas.
- Their proposed model fits the data better than additive linear and nonlinear models.
- They find evidence of a nonlinear ozone effect and an ozone-temperature interaction at higher temperatures and ozone concentrations.
- Climate change-induced increases in ambient temperatures may exacerbate the negative health impacts associated with exposure to high levels of ambient ozone.
- Action is needed to mitigate climate change by reducing greenhouse gas emissions as well as implementing measures to reduce exposure to harmful air pollutants such as ground-level ozone.

## Summary

Climate change is a pressing issue with far-reaching consequences for public health. One of the ways in which climate change affects human health is through changes in ambient ozone levels and temperatures. While much research has focused on the effect of short-term ozone exposures on mortality and morbidity while controlling for temperature as a confounder, less is known about the joint effects of ozone and temperature. To address this knowledge gap, Ander Wilson, Ana G. Rappold, Lucas M. Neas, and Brian J. Reich propose a spatial, semi-parametric model to estimate the joint ozone-temperature risk surfaces in 95 US urban areas. Their methodology restricts the ozone-temperature risk surfaces to be monotone in ozone and allows for both nonadditive and nonlinear effects of ozone and temperature. Using data from the National Mortality and Morbidity Air Pollution Study (NMMAPS), they show that their proposed model fits the data better than additive linear and nonlinear models. They then examine the synergistic effect of ozone and temperature both nationally and locally and find evidence of a nonlinear ozone effect and an ozone-temperature interaction at higher temperatures and ozone concentrations. Their findings suggest that climate change-induced increases in ambient temperatures may exacerbate the negative health impacts associated with exposure to high levels of ambient ozone. This underscores the importance of taking action to mitigate climate change by reducing greenhouse gas emissions as well as implementing measures to reduce exposure to harmful air pollutants such as ground-level ozone.