Abstract Long‐term exposure to ambient fine particulate matter (PM2.5) is the second leading risk factor of premature death in Sub‐Saharan Africa. We use GEOS‐Chem to quantify the effects of (a) trash burning, (b) residential solid‐fuel burning, and (c) open biomass burning (BB) (i.e., landscape fires) on ambient PM2.5and PM2.5‐attributable mortality in Africa. Using a series of sensitivity simulations, we excluded each of the three combustion sources in each of five African regions. We estimate that in 2017 emissions from these three combustion sources within Africa increased global ambient PM2.5by 2%, leading to 203,000 (95% confidence interval: 133,000–259,000) premature mortalities yr−1globally and 167,000 premature mortalities yr−1in Africa. BB contributes more ambient PM2.5‐related premature mortalities per year (63%) than residential solid‐fuel burning (29%) and trash burning (8%). Open BB in Central Africa leads to the largest number of PM2.5‐attributed mortalities inside the region, while trash burning in North Africa and residential solid‐fuel burning in West Africa contribute the most regional mortalities for each source. Overall, Africa has a unique ambient air pollution profile because natural sources, such as windblown dust and BB, contribute strongly to ambient PM2.5levels and PM2.5‐related mortality. Air pollution policies may need to focus on taking preventative measures to avoid exposure to ambient PM2.5from these less‐controllable sources.
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Environmental Association of Burning Agricultural Biomass in the Indus River Basin
Intensification of smog episodes, following harvesting of paddy crops in agricultural plains of the Indus basin in the Indian subcontinent, are often attributed to farming practice of burning standing stubble during late autumn (October, November) months. Biomass burning (paddy stubble residual) is a preferred technique to clear farmlands for centuries by farmers in that basin. However, despite stable agricultural landholding and yield, smog is being increasingly associated with burning agricultural biomass, thus creating a paradox. Here, we show that the concentration of smog (NOx, PM2.5, SO2) in the ambient air exceeds the safe threshold limits throughout the entire year in the region. This study argues that agricultural biomass burning is an ephemeral event in the basin that may act as a catalyst to a deteriorated air quality in the entire region. Results further demonstrate that simultaneous saturation of air pollutants along with high ambient moisture content and low wind speeds following the monsoon season are strongly related to aggravated smog events. Findings from this study should help make holistic mitigation and intervention policies to monitor air quality for sustainability of public health in agricultural regions where farming activities are a dominant economic driver for society.
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- Award ID(s):
- 2001664
- PAR ID:
- 10220243
- Date Published:
- Journal Name:
- Geohealth
- Volume:
- 4
- Issue:
- 11
- ISSN:
- 2471-1403
- Page Range / eLocation ID:
- e2020GH000281
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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