Mapping and modeling desertification and its impact on aeolian dust and human health in Central Asia

This proposal is aimed at a systematic assessment of desertification and its impact on aeolian dust, air quality, and human health in Central Asia during the past twenty years (2000-2019). By leveraging the proposal team’s past and ongoing research on Asian drylands and dust, this proposal seeks to address several important knowledge gaps in the mechanism, relationship, and impact of desertification occurring in the dryland ecosystems of Central Asia. The motivation behind this study is that desertification poses an imminent threat to dryland ecosystems and human well-being, and combating desertification, which comes with climate mitigation co-benefits, depends on accurate knowledge of the spatial pattern, temporal trajectory, driving processes, and societal impacts of desertification. In Central Asia, human-driven desertification processes have led to severe loss of land productivity and degradation of air quality. So far, there has been limited knowledge of the health impact and associated external cost to society of desertification-induced air pollution, despite it being a long-standing problem in the area. To guide actions of combating desertification, this study is designed to address the following science questions: (1) What is the current extent of desertification and what are the major drivers? (2) To what extent does desertification contribute to the region’s aeolian dust and air pollution? (3) How do climate variations and desertification affect the long-term dust activity? (4) What are the health and socioeconomic impacts of desertification-induced air pollution? To answer these questions, an integrated desertification-pollution-impact pathway approach will be developed by combining remote sensing, statistical and physical modeling, environmental justice analysis, and economic valuation of air pollution. The specific objectives of this study are: (1) Map the spatiotemporal dynamics of desertification using multiple remote sensing-based indicators, and determine the roles of climate and socioeconomic drivers; (2) Quantify the contribution of desertification to aeolian dust and particulate matter pollution using a process-based model system; (3) Synthesize surface observations, remote sensing, and global model reanalysis to characterize the spatiotemporal variability of aeolian dust; and (4) Assess the environmental justice and health impact of human exposure to outdoor particulate matter pollution. The primary outcome of this project will consist of an updated assessment of desertification in Central Asia in accordance with the reporting guidelines of Sustainable Development Goals on Land Degradation Neutrality, process-level analysis of the relationship between desertification, aeolian dust, and air pollution, and assessment of the health and socioeconomic impact of air pollution in Central Asia.