Assessing Atmospheric Mercury Dynamics: A Comparative Analysis of Current Anthropogenic Emission Inventories and their Implications for Concentration and Deposition in India

Anthropogenic mercury emissions pose significant risks to both human health and ecosystems, particularly when transformed into methylmercury. India stands as the second-largest contributor to mercury emissions, estimated at 144.7 tonnes of Hg/year, with uncertainties ranging from 75 to 330 Mg/year 1. India ratified the Minamata Convention in 2018, committing to address and mitigate mercury pollution2. Knowledge of Indian specific characteristics of mercury emission sources is essential for implementing effective mitigation strategies. However, India currently lacks a national emission inventory, with only limited estimates available3. This research explores the impact of different anthropogenic emission inventories (AMAP/UNEP-2010, EDGAR, STREETS, AMAP/UNEP-2015) on mercury concentration and deposition patterns in India. We employ nested simulations of the chemical transport model GEOS-Chem over India for the year 2013-15. The current study also investigates the impact of grid resolution and meteorology on spatial distribution of Hg concentrations and deposition using MERRA-2 and GEOS-FP meterological datasets. Additionally, the study delves into the seasonal variations of Hg concentration and deposition across different regions of India, analysing their correlation with various meteorological parameters (such as rainfall). These findings are crucial for gaining insights into the dynamics of the mercury cycle in the environment. Furthur results will be presented. References: 1.AMAP/UNEP (2013) Technical background report for the global mercury assessment 2013. Arctic Monitoring and Assessment Programme/UNEP Chemicals Branch, Oslo/Geneva 2.UNEP. Parties and Signatories Minamata Convention on Mercury. https://www.mercuryconvention.org/en/parties (accessed 2024-01-09) 3.Sharma, B. M., Bharat, G. K., ebkov, K., Scheringer, M. (2019). Implementation of the Minamata Convention to manage mercury pollution in India: challenges and opportunities. Environmental Sciences Europe, 31, 1-12.