Table 1.
Projected impacts of climate change on ozone-related health effects.
| Area | Health effect | Model | Climate scenario time slices | Temperature increase and baseline | Population projections and other assumptions | Main results | Reference |
|---|---|---|---|---|---|---|---|
| New York metropolitan region, United States | Ozone-related deaths by county | Concentration– response function from published epidemiologic literature. Gridded ozone concentrations from CMAQ. | GISS driven by SRES A2, downscaled using MM5. 2050s | 1.6–3.2°C in 2050s compared with 1990s | Population and age structure held constant at year 2000. Assumes no change from U.S, EPA 1996 national emissions inventory and A2; consistent increases in NOx and VOCs by 2050s. | A2 climate only: 4.5% increase in ozone- related deaths. Ozone elevated in all counties. A2 climate and precursors: 4.4% increase in ozone- related-deaths. (Ozone not elevated in all areas due to NOx interactions.) | Knowlton et al. 2004 |
| 50 cities, eastern United States | Ozone-related hospitalizations and deaths | Concentration– response function from published epidemiologic literature. Gridded ozone concentrations from CMAQ. | GISS driven by SRES A2, downscaled using MM5. 2050s | 1.6–3.2°C in 2050s compared with 1990s | Population and age structure held constant at year 2000. Assumes no change from U.S. EPA 1996 national emissions inventory and A2-consistent increases in NOx and VOCs by 2050s. | Maximum ozone concentrations increase for all cities, with the largest increases in cities with currently higher concentrations; 68% increase in average number of days/summer exceeding the 8-hr regulatory standard, resulting in 0.11–0.27% increase in nonaccidental mortality and an average 0.31% increase in cardiovascular disease mortality. | Bell et al. 2007 |
| Los Angeles and San Diego regions, California, United States | Ozone-related hospitalizations and deaths | Concentration– response function from published epidemiologic literature. Gridded ozone concentrations. | HadCM3 driven by SRES A2, downscaled using MM5, then a photochemical model (CAMx) in the 2050s and 2090s | 2.1– 2.7°C in 2050s, and 4.6 to 5.5°C in 2090s | Population and age structure held constant. Assumes no change from U.S. EPA 1997 national emissions inventory and A2- consistent increases in NOx and VOCs by 2050s and 2090s. | Average increase in ozone peaks of 2.0–3.2 ppb in the 2050s, and 3.1–4.8 ppb in the 2090s. Increases in maximum peak concentrations are 2- to 3-fold higher. Percent increase in daily mortality in the 2050s range from 0.08 to 0.46 depending on the exposure–response relationship. Increases in the 2090s are 0.12–0.69. Projected increases in hospital admissions are higher. | Hwang et al. 2004 |
| England and Wales, United Kingdom | Exceedance days (ozone, particulates, NOx) | Statistical, based on meteorologic factors for high pollutant days (temperature, wind speed); projections of U.K. and northwest Europe urban traffic emissions of ozone precursors. | UKCIP scenarios 2020s, 2050s, 2080s. | 0.57–1.38°C in 2020s; 0.89 –2.44°C in 2050s; 1.13–3.47°C in 2080s compared with 1961–1990 baseline | Population and age structure held constant. | Over all time periods, large decreases in days with high particulates and SO2; small decrease in other pollutants except ozone, which increases. If a threshold is assumed, then the increase in health effects due to ozone would be relatively small. If no threshold is assumed, then ozone is projected to increase premature deaths by 10, 20, and 40% for the years 2020, 2050, and 2080, respectively. | Anderson et al. 2001 |
| 10 world regions | Premature mortality from acute ozone exposure | Ozone–mortality coefficient from a study of 95 cities in the United States. | Coupled general circulation model with interactive chemistry (LMDz-INCA) driven by SRES A2 for 2030. | Baseline simulated for 2000 | Population growth and emissions under SRES A2. One realization included recently enacted legislative to control ozone, and another assumed maximum feasible reduction of ozone precursors. | Large increase in ozone in 2030 under the A2 scenario; global population–weighted 8-hr ozone increased 9.4 ppbv. Along with population growth, this was associated with approximately 500,000 additional deaths. Using a threshold of 25 ppbv, 191,000 deaths worldwide could be avoided using currently enacted legislation, and 458,000 deaths could be avoided using maximum feasible reduction technologies. | West et al. 2007 |
Abbreviations: CMAQ, Community Multiscale Air Quality; GISS, Goddard Institute for Space Studies; HadCM3, one of the climate models from the Hadley Centre, United Kingdom; NOx, nitrogen oxides; UKCIP, United Kingdom Climate Impacts Programme; VOC, volatile organic compound. Modified from Confalonieri et al. (2007).