Climate change plus ozone pollution is a lethal combination that adversely affects human health, agriculture productivity, ecosystems, and the world economy. Currently, there is a growing concern ...that climate change may aggravate ozone pollution even after reducing anthropogenic precursor source activities. Part of it may be due to temperature-enhanced natural precursor emissions of ozone, increased stratospheric–tropospheric exchange of ozone, more frequent periods with meteorologically stagnant conditions favouring pollution build-up, changes in wetland methane emissions, and enhanced concentrations of atmospheric carbon dioxide. The quantification of climate change and ozone levels involves complex chemical, radiative, biogenic, and transport processes and feedback that are difficult to fully comprehend. Further, the fact that ozone is a short-lived climate forcer and a potent greenhouse gas provides a feedback loop and makes climate-ozone links even more multifaceted. This review examines the up-to-date understanding of the processes regulating tropospheric ozone from regional to global scales and the associated climate connections. We explore the recent findings in ozone precursor emissions from natural sources, ozone formation chemistry, its transport on hemispheric scales, future plausible ozone concentrations in different shared socioeconomic pathways, and changes in the radiative forcing of ozone. The review demonstrates the challenges and limitations associated with climate-ozone linkages and their incorporation in models, which are due to uncertainties in magnitude and signs of projected precursor emissions in response to future climate change and also due to the difference in models.
Ozone pollution is a growing problem in many developing countries posing challenges not only to air quality but also affecting agricultural productivity and human well-being. This is the first study ...in the Indo-Gangetic Plain exploring how the spatial variation and severity of tropospheric ozone affect both wheat yield and all-cause mortality. We estimated that ozone-related cumulative crop production loss for wheat in selected districts of IGP was 3.4 million tonnes during the study period (2019–2021), which amounted to 923 million USD. The production-weighted Relative Yield Loss (RYL) for wheat in the IGP was 9.3 % in 2019, 12.8 % in 2020, and 11.3 % in 2021. The losses incurred in 2021 could contribute to fulfilling the wheat requirements of 11.4 million people. We also assess the health and economic gains resulting from the attainment of the World Health Organization Air Quality Guidelines (WHO AQG) for ozone concentrations. It is estimated that interventions that achieve AQG would have averted 11,407 premature deaths in 2021 translating into an impressively large health and economic gain. The annual benefits in 2021 totaled to 34 billion USD. We observe that Uttar Pradesh experienced the highest losses, both in terms of crop damage and premature deaths. Our study observes that implementing policies to prepone the planting of wheat enhances food security by mitigating yield losses. Mitigating the health impact of ambient ozone necessitates a reduction in anthropogenic emissions and to attain this objective, we propose adopting an exposure-integrated source reduction approach.
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•Ozone pollution poses severe threat to food security and human health.•RYL for wheat 11.3 % in IGP for 2021•Economic Cost of 34 billion USD due to crop and health loss in 2021
Achieving global food security and ensuring sustainable agriculture, the dual objectives of the second Sustainable Development Goal (SDG 2), necessitate immediate and collaborative efforts from ...developing and developed nations. The adverse effects of ozone on crop yields have the potential to significantly undermine the United Nations' ambitious target of attaining food security and ending hunger by 2030. This review examines the causes of growing tropospheric ozone, especially in India and China which lead to a substantial reduction in crop yield and forest biomass. The findings show that a nexus of high population, rapid urbanization and regional pollution sources aggravates the problem in these countries. It elucidates that when plants are exposed to ozone, specific cellular pathways are triggered, resulting in changes in the expression of genes related to hormone production, antioxidant metabolism, respiration, and photosynthesis. Assessing the risks associated with ozone exposure involves using response functions that link exposure-based and flux-based measurements to variables like crop yield. Precisely quantifying the losses in yield and economic value in food crops due to current ozone levels is of utmost importance in comprehending the risks ozone poses to global food security. We conclude that policymakers should focus on implementing measures to decrease the emissions of ozone precursors, such as enhancing vehicle fuel efficiency standards and promoting the use of cleaner energy sources. Additionally, efforts should be directed toward mapping or developing crop varieties that can tolerate ozone, applying protective measures at critical stages of plant growth and establishing ozone-related vegetation protection standards.
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•Tropospheric ozone jeopardises food security.•Use of OTC and FACE systems to evaluate O3-crop response.•Exposure-based index AOT40 widely used in studies.•Use of emission control, chemical protectants, and bioengineering techniques to prevent yield losses.
The problem of air pollution poses a major challenge in the city of Taj, Agra because of rapid urbanization and tourism. Research on PM2.5/PM10 ratio contributes to a deeper understanding of the air ...pollution scenario and promoting sustainable development. This study was carried out at a suburban site in Agra (Jan 2021-Dec, 2022). We analyzed PM2.5/PM10 ratios, and their correlation with Air Quality Index and meteorological factors using various statistical approaches in the OpenAir package in RStudio. The mean concentrations of PM2.5 and PM10 were 46 and 67 μg/m3, respectively. The PM2.5/PM10 ratio was 0.65, indicating fine particulate dominance. Diurnal, intra-annual, and weekly cycles of PM2.5, PM10, and PM2.5/PM10 ratios were examined. PM2.5/PM10 ratio increased with increasing AQI. Correlation analysis revealed, a strong positive correlation (r = 0.94) between PM10 and PM2.5 while the PM2.5/PM10 ratios showed negative association with wind speed (WS), and temperature, and positive association with relative humidity (RH). Higher RH led to higher PM2.5/PM10 ratios indicating worsening of PM2.5 pollution during winter and post-monsoon. Bivariate polar plots exhibited the lowest PM2.5/PM10 ratios in summer at high WS (>10 m/s) from the west, and the highest PM2.5/PM10 ratios in winter and post-monsoon at low WS (<10 m/s).
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•PM2.5 and PM10 (r = 0.94) were highly correlated.•PM2.5/PM10 ratio was higher in winter and post-monsoon.•Higher relative humidity led to higher PM2.5/PM10 ratio.•PM2.5/PM10 ratio showed negative association with wind speed and temperature.