Kristie L.; McGregor, Glenn (2008-11-01). "Climate Change, Tropospheric Ozone and Particulate Matter, and Health Impacts". Environmental Health Perspectives Climate change affects human health in many ways, including an increase in heat-related illnesses and deaths, worsened air quality, the spread of infectious diseases, and health risks associated with extreme weather such as floods and storms. Rising global temperatures and changes in weather patterns are increasing the severity of heat waves and extreme weather events. These events in turn have di The relationship between surface ozone (also called ground-level ozone) and ambient temperature is complex. Changes in air temperature and water content affect the air's chemistry and the rates of chemical reactions that create and remove ozone. Many chemical reaction rates increase with temperature and lead to increased ozone production. Climate change projections show that rising temperatures and water vapour in the atmosphere will likely increase surface ozone in polluted areas like the eastern United States. On the other hand, ozone concentrations could decrease in a warming climate if anthropogenic ozone-precursor emissions (e.g., nitrogen oxides) continue to decrease through implementation of policies and practices. Therefore, future surface ozone concentrations depend on the climate change mitigation steps taken (more or less methane emissions) as well as air pollution control steps taken. High surface ozone concentrations often occur during heat waves in the United States. Throughout much of the eastern United States, ozone concentrations during heat waves are at least 20% higher than the summer average. Broadly speaking, surface ozone levels are higher in cities with high levels of air pollution. Ozone pollution in urban areas affects denser populations, and is worsened by high populations of vehicles, which emit pollutants NO2 and VOCs, the main contributors to problematic ozone levels. There is a great deal of evidence to show that surface ozone can harm lung function and irritate the respiratory system. Exposure to ozone (and the pollutants that produce it) is linked to premature death, asthma, bronchitis, heart attack, and other cardiopulmonary problems. High ozone concentrations irritate the lungs and thus affect respiratory function, especially among people with asthma. People who are most at risk from breathing in ozone air pollution are those with respiratory issues, children, older adults and those who typically spend long periods of time outside such as construction workers. A 2026 UNICEF report on children's climate risk found that children are particularly exposed to rising heat: globally, the most widespread combination of hazards…

Due to its effects on the atmospheric lifetime of methane, the burdens of tropospheric ozone and growth of secondary organic aerosol, isoprene is central among the biogenic compounds that need to be taken into account for assessment of anthropogenic air pollution-climate change interactions. Lack of process-understanding regarding leaf isoprene production as well as of suitable observations to constrain and evaluate regional or global simulation results add large uncertainties to past, present and future emissions estimates. Focusing on contemporary climate conditions, we compare three global isoprene models that differ in their representation of vegetation and isoprene emission algorithm. We specifically aim to investigate the between- and within model variation that is introduced by varying some of the models' main features, and to determine which spatial and/or temporal features are robust between models and different experimental set-ups. In their individual standard configurations, the models broadly agree with respect to the chief isoprene sources and emission seasonality, with maximum monthly emission rates around 20–25 Tg C, when averaged by 30-degree latitudinal bands. They also indicate relatively small (approximately 5 to 10 % around the mean) interannual variability of total global emissions. The models are sensitive to changes in one or more of their main model components and drivers (e.g., underlying vegetation fields, climate input) which can yield increases or

A range of solar radiation management (SRM) techniques has been proposed to counter anthropogenic climate change. Here, we examine the potential effects of stratospheric sulfate aerosols and solar insolation reduction on tropospheric ozone and ozone at Earth's surface. Ozone is a key air pollutant, which can produce respiratory diseases and crop damage. Using a version of the Community Earth System Model from the National Center for Atmospheric Research that includes comprehensive tropospheric and stratospheric chemistry, we model both stratospheric sulfur injection and solar irradiance reduction schemes, with the aim of achieving equal levels of surface cooling relative to the Representative Concentration Pathway 6.0 scenario. This allows us to compare the impacts of sulfate aerosols and solar dimming on atmospheric ozone concentrations. Despite nearly identical global mean surface temperatures for the two SRM approaches, solar insolation reduction increases global average surface ozone concentrations, while sulfate injection decreases it. A fundamental difference between the two geoengineering schemes is the importance of heterogeneous reactions in the photochemical ozone balance with larger stratospheric sulfate abundance, resulting in increased ozone depletion in mid- and high latitudes. This reduces the net transport of stratospheric ozone into the troposphere and thus is a key driver of the overall decrease in surface ozone. At the same time, the change in stratospheric

Increasing levels of CO 2 and tropospheric ozone (O 3 ) due to climate change are contributing to reduced plant health and unstable crop yield production 1 . The inoculation of plant roots with beneficial fungi or bacteria can increase plant health 2 . However, this is often studied under very controlled conditions and it is unknown how climate change or interactions with other species can alter the resulting benefits. Here we show that the rhizosphere bacterium Acidovorax radicis N35 can increase plant growth and reduce insect growth – with increased impact in a high-stress elevated O 3 environment, but reduced impact under elevated CO 2 . In a fully-factorial climate chamber experiment we disentangled the impacts of climate factors (elevated CO 2 and elevated O 3 ) and biotic interactions (plant cultivar, sap-feeding insects and earthworms) on cereal growth and insect suppression mediated by A. radicis N35. Earthworms promoted plant aboveground growth, whereas A. radicis N35 promoted root growth, and overall plant growth was higher when both species were present. However, earthworms also promoted insect growth and therefore increased plant damage through herbivory. While A. radicis N35 inoculation was able to mitigate these negative effects to some extent under an ambient environment this was lost under climate change conditions. Our results show that knowledge-based solutions for sustainable agriculture should include biotic interactions and must be tested across variable

However, on an absolute scale, changes in the stratosphere were strongest (relative decrease: 6 to 7% per decade at 20-22 km). The present scientific theories of the two ozone problems are reviewed: stratospheric ozone decrease was caused by the anthropogenic emissions of fluorochlorocarbons and other compounds mainly released from the earth surface. Tropospheric ozone has increased due to photochemical production of mainly anthropogenically emitted nitrogen oxides, volatile organic compounds and CO. Published in Schweizerische Rundschau fur Medizin Praxis = Revue suisse de medecine Praxis (1992)